Merge branch '3.0' of https://github.com/taosdata/TDengine into feat/stream_compression

docs/en/14-reference/03-connector/07-python.mdx

@@ -80,8 +80,8 @@ pip3 install git+https://github.com/taosdata/taos-connector-python.git
 
 ### Verify
 
-<Tabs groupId="connect" default="native">
-<TabItem value="rest" label="native connection">
+<Tabs defaultValue="rest">
+<TabItem value="native" label="native connection">
 
 For native connection, you need to verify that both the client driver and the Python connector itself are installed correctly. The client driver and Python connector have been installed properly if you can successfully import the `taos` module. In the Python Interactive Shell, you can type.
 
@@ -118,7 +118,7 @@ Requirement already satisfied: taospy in c:\users\username\appdata\local\program
 
 Before establishing a connection with the connector, we recommend testing the connectivity of the local TDengine CLI to the TDengine cluster.
 
-<Tabs>
+<Tabs defaultValue="rest">
 <TabItem value="native" label="native connection">
 
 Ensure that the TDengine instance is up and that the FQDN of the machines in the cluster (the FQDN defaults to hostname if you are starting a standalone version) can be resolved locally, by testing with the `ping` command.
@@ -173,7 +173,7 @@ If the test is successful, it will output the server version information, e.g.
 
 The following example code assumes that TDengine is installed locally and that the default configuration is used for both FQDN and serverPort.
 
-<Tabs>
+<Tabs defaultValue="rest">
 <TabItem value="native" label="native connection" groupId="connect">
 
 ```python
@@ -219,7 +219,7 @@ All arguments to the `connect()` function are optional keyword arguments. The fo
 
 ### Basic Usage
 
-<Tabs default="native" groupId="connect">
+<Tabs defaultValue="rest">
 <TabItem value="native" label="native connection">
 
 ##### TaosConnection class
@@ -289,7 +289,7 @@ For a more detailed description of the `sql()` method, please refer to [RestClie
 
 ### Used with pandas
 
-<Tabs default="native" groupId="connect">
+<Tabs defaultValue="rest">
 <TabItem value="native" label="native connection">
 
 ```python

docs/en/14-reference/03-connector/09-csharp.mdx

@@ -97,7 +97,7 @@ dotnet add exmaple.csproj reference src/TDengine.csproj
 ## Establish a Connection
 
 
-<Tabs defaultValue="native">
+<Tabs defaultValue="rest">
 
 <TabItem value="native" label="Native Connection">
 
@@ -173,7 +173,7 @@ ws://localhost:6041/test
 
 #### SQL Write
 
-<Tabs defaultValue="native">
+<Tabs defaultValue="rest">
 
 <TabItem value="native" label="Native Connection">
 
@@ -204,7 +204,7 @@ ws://localhost:6041/test
 
 #### Parameter Binding
 
-<Tabs defaultValue="native">
+<Tabs defaultValue="rest">
 
 <TabItem value="native" label="Native Connection">
 
@@ -227,7 +227,7 @@ ws://localhost:6041/test
 
 #### Synchronous Query
 
-<Tabs defaultValue="native">
+<Tabs defaultValue="rest">
 
 <TabItem value="native" label="Native Connection">
 

docs/en/20-third-party/02-prometheus.md

@@ -89,3 +89,7 @@ VALUE    TIMESTAMP
 
 ```
 
+:::note
+
+- TDengine will automatically create unique IDs for sub-table names by the rule.
+:::

docs/en/20-third-party/03-telegraf.md

@@ -71,7 +71,7 @@ Query OK, 3 row(s) in set (0.013269s)
 :::note
 
 - TDengine take influxdb format data and create unique ID for table names by the rule.
-The user can configure `smlChildTableName` paramter to generate specified table names if he/she needs. And he/she also need to insert data with specified data format.
+The user can configure `smlChildTableName` parameter to generate specified table names if he/she needs. And he/she also need to insert data with specified data format.
 For example, Add `smlChildTableName=tname` in the taos.cfg file. Insert data `st,tname=cpu1,t1=4 c1=3 1626006833639000000` then the table name will be cpu1. If there are multiple lines has same tname but different tag_set, the first line's tag_set will be used to automatically creating table and ignore other lines. Please refer to [TDengine Schemaless](/reference/schemaless/#Schemaless-Line-Protocol)
 :::
 

docs/en/20-third-party/05-collectd.md

@@ -72,3 +72,7 @@ taos> select * from collectd.memory_value limit 10;
 Query OK, 10 row(s) in set (0.010348s)
 ```
 
+:::note
+
+- TDengine will automatically create unique IDs for sub-table names by the rule.
+:::

docs/en/20-third-party/07-icinga2.md

@@ -36,11 +36,12 @@ After waiting about 10 seconds, use the TDengine CLI to query TDengine to verify
 
 ```
 taos> show databases;
-              name              |      created_time       |   ntables   |   vgroups   | replica | quorum |  days  |           keep           |  cache(MB)  |   blocks    |   minrows   |   maxrows   | wallevel |    fsync    | comp | cachelast | precision | update |   status   |
-====================================================================================================================================================================================================================================================================================
- log                            | 2022-04-20 07:19:50.260 |          11 |           1 |       1 |      1 |     10 | 3650                     |          16 |           6 |         100 |        4096 |        1 |        3000 |    2 |         0 | ms        |      0 | ready      |
- icinga2                        | 2022-04-20 12:11:39.697 |          13 |           1 |       1 |      1 |     10 | 3650                     |          16 |           6 |         100 |        4096 |        1 |        3000 |    2 |         0 | ns        |      2 | ready      |
-Query OK, 2 row(s) in set (0.001867s)
+              name              |
+=================================
+ information_schema             |
+ performance_schema             |
+ icinga2                        |
+Query OK, 3 row(s) in set (0.001867s)
 
 taos> use icinga2;
 Database changed.
@@ -72,3 +73,8 @@ taos> show stables;
  icinga.service.users.state     | 2022-04-20 12:11:39.704 |       2 |      1 |           1 |
 Query OK, 22 row(s) in set (0.002317s)
 ```
+
+:::note
+
+- TDengine will automatically create unique IDs for sub-table names by the rule.
+:::

docs/en/28-releases/01-tdengine.md

@@ -6,6 +6,10 @@ description: TDengine release history, Release Notes and download links.
 
 import Release from "/components/ReleaseV3";
 
+## 3.0.1.4
+
+<Release type="tdengine" version="3.0.1.4" />
+
 ## 3.0.1.3
 
 <Release type="tdengine" version="3.0.1.3" />

docs/en/28-releases/02-tools.md

@@ -6,6 +6,10 @@ description: taosTools release history, Release Notes, download links.
 
 import Release from "/components/ReleaseV3";
 
+## 2.2.4
+
+<Release type="tools" version="2.2.4" />
+
 ## 2.2.3
 
 <Release type="tools" version="2.2.3" />

docs/zh/20-third-party/02-prometheus.md

@@ -88,3 +88,7 @@ VALUE    TIMESTAMP
 
 ```
 
+:::note
+
+- TDengine 默认生成的子表名是根据规则生成的唯一 ID 值。
+:::

docs/zh/20-third-party/05-collectd.md

@@ -72,3 +72,7 @@ taos> select * from collectd.memory_value limit 10;
 Query OK, 10 row(s) in set (0.010348s)
 ```
 
+:::note
+
+- TDengine 默认生成的子表名是根据规则生成的唯一 ID 值。
+:::

docs/zh/20-third-party/07-icinga2.md

@@ -37,11 +37,12 @@ sudo systemctl restart icinga2
 
 ```
 taos> show databases;
-              name              |      created_time       |   ntables   |   vgroups   | replica | quorum |  days  |           keep           |  cache(MB)  |   blocks    |   minrows   |   maxrows   | wallevel |    fsync    | comp | cachelast | precision | update |   status   |
-====================================================================================================================================================================================================================================================================================
- log                            | 2022-04-20 07:19:50.260 |          11 |           1 |       1 |      1 |     10 | 3650                     |          16 |           6 |         100 |        4096 |        1 |        3000 |    2 |         0 | ms        |      0 | ready      |
- icinga2                        | 2022-04-20 12:11:39.697 |          13 |           1 |       1 |      1 |     10 | 3650                     |          16 |           6 |         100 |        4096 |        1 |        3000 |    2 |         0 | ns        |      2 | ready      |
-Query OK, 2 row(s) in set (0.001867s)
+              name              |
+=================================
+ information_schema             |
+ performance_schema             |
+ icinga2                        |
+Query OK, 3 row(s) in set (0.001867s)
 
 taos> use icinga2;
 Database changed.
@@ -73,3 +74,9 @@ taos> show stables;
  icinga.service.users.state     | 2022-04-20 12:11:39.704 |       2 |      1 |           1 |
 Query OK, 22 row(s) in set (0.002317s)
 ```
+
+
+:::note
+
+- TDengine 默认生成的子表名是根据规则生成的唯一 ID 值。
+:::

docs/zh/28-releases/01-tdengine.md

@@ -6,6 +6,10 @@ description: TDengine 发布历史、Release Notes 及下载链接
 
 import Release from "/components/ReleaseV3";
 
+## 3.0.1.4
+
+<Release type="tdengine" version="3.0.1.4" />
+
 ## 3.0.1.3
 
 <Release type="tdengine" version="3.0.1.3" />

docs/zh/28-releases/02-tools.md

@@ -6,6 +6,10 @@ description: taosTools 的发布历史、Release Notes 和下载链接
 
 import Release from "/components/ReleaseV3";
 
+## 2.2.4
+
+<Release type="tools" version="2.2.4" />
+
 ## 2.2.3
 
 <Release type="tools" version="2.2.3" />

include/common/ttokendef.h

@@ -227,110 +227,111 @@
 #define TK_WEND                 209
 #define TK_WDURATION            210
 #define TK_IROWTS               211
-#define TK_CAST                 212
-#define TK_NOW                  213
-#define TK_TODAY                214
-#define TK_TIMEZONE             215
-#define TK_CLIENT_VERSION       216
-#define TK_SERVER_VERSION       217
-#define TK_SERVER_STATUS        218
-#define TK_CURRENT_USER         219
-#define TK_COUNT                220
-#define TK_LAST_ROW             221
-#define TK_CASE                 222
-#define TK_END                  223
-#define TK_WHEN                 224
-#define TK_THEN                 225
-#define TK_ELSE                 226
-#define TK_BETWEEN              227
-#define TK_IS                   228
-#define TK_NK_LT                229
-#define TK_NK_GT                230
-#define TK_NK_LE                231
-#define TK_NK_GE                232
-#define TK_NK_NE                233
-#define TK_MATCH                234
-#define TK_NMATCH               235
-#define TK_CONTAINS             236
-#define TK_IN                   237
-#define TK_JOIN                 238
-#define TK_INNER                239
-#define TK_SELECT               240
-#define TK_DISTINCT             241
-#define TK_WHERE                242
-#define TK_PARTITION            243
-#define TK_BY                   244
-#define TK_SESSION              245
-#define TK_STATE_WINDOW         246
-#define TK_SLIDING              247
-#define TK_FILL                 248
-#define TK_VALUE                249
-#define TK_NONE                 250
-#define TK_PREV                 251
-#define TK_LINEAR               252
-#define TK_NEXT                 253
-#define TK_HAVING               254
-#define TK_RANGE                255
-#define TK_EVERY                256
-#define TK_ORDER                257
-#define TK_SLIMIT               258
-#define TK_SOFFSET              259
-#define TK_LIMIT                260
-#define TK_OFFSET               261
-#define TK_ASC                  262
-#define TK_NULLS                263
-#define TK_ABORT                264
-#define TK_AFTER                265
-#define TK_ATTACH               266
-#define TK_BEFORE               267
-#define TK_BEGIN                268
-#define TK_BITAND               269
-#define TK_BITNOT               270
-#define TK_BITOR                271
-#define TK_BLOCKS               272
-#define TK_CHANGE               273
-#define TK_COMMA                274
-#define TK_COMPACT              275
-#define TK_CONCAT               276
-#define TK_CONFLICT             277
-#define TK_COPY                 278
-#define TK_DEFERRED             279
-#define TK_DELIMITERS           280
-#define TK_DETACH               281
-#define TK_DIVIDE               282
-#define TK_DOT                  283
-#define TK_EACH                 284
-#define TK_FAIL                 285
-#define TK_FILE                 286
-#define TK_FOR                  287
-#define TK_GLOB                 288
-#define TK_ID                   289
-#define TK_IMMEDIATE            290
-#define TK_IMPORT               291
-#define TK_INITIALLY            292
-#define TK_INSTEAD              293
-#define TK_ISNULL               294
-#define TK_KEY                  295
-#define TK_NK_BITNOT            296
-#define TK_NK_SEMI              297
-#define TK_NOTNULL              298
-#define TK_OF                   299
-#define TK_PLUS                 300
-#define TK_PRIVILEGE            301
-#define TK_RAISE                302
-#define TK_REPLACE              303
-#define TK_RESTRICT             304
-#define TK_ROW                  305
-#define TK_SEMI                 306
-#define TK_STAR                 307
-#define TK_STATEMENT            308
-#define TK_STRING               309
-#define TK_TIMES                310
-#define TK_UPDATE               311
-#define TK_VALUES               312
-#define TK_VARIABLE             313
-#define TK_VIEW                 314
-#define TK_WAL                  315
+#define TK_QTAGS                212
+#define TK_CAST                 213
+#define TK_NOW                  214
+#define TK_TODAY                215
+#define TK_TIMEZONE             216
+#define TK_CLIENT_VERSION       217
+#define TK_SERVER_VERSION       218
+#define TK_SERVER_STATUS        219
+#define TK_CURRENT_USER         220
+#define TK_COUNT                221
+#define TK_LAST_ROW             222
+#define TK_CASE                 223
+#define TK_END                  224
+#define TK_WHEN                 225
+#define TK_THEN                 226
+#define TK_ELSE                 227
+#define TK_BETWEEN              228
+#define TK_IS                   229
+#define TK_NK_LT                230
+#define TK_NK_GT                231
+#define TK_NK_LE                232
+#define TK_NK_GE                233
+#define TK_NK_NE                234
+#define TK_MATCH                235
+#define TK_NMATCH               236
+#define TK_CONTAINS             237
+#define TK_IN                   238
+#define TK_JOIN                 239
+#define TK_INNER                240
+#define TK_SELECT               241
+#define TK_DISTINCT             242
+#define TK_WHERE                243
+#define TK_PARTITION            244
+#define TK_BY                   245
+#define TK_SESSION              246
+#define TK_STATE_WINDOW         247
+#define TK_SLIDING              248
+#define TK_FILL                 249
+#define TK_VALUE                250
+#define TK_NONE                 251
+#define TK_PREV                 252
+#define TK_LINEAR               253
+#define TK_NEXT                 254
+#define TK_HAVING               255
+#define TK_RANGE                256
+#define TK_EVERY                257
+#define TK_ORDER                258
+#define TK_SLIMIT               259
+#define TK_SOFFSET              260
+#define TK_LIMIT                261
+#define TK_OFFSET               262
+#define TK_ASC                  263
+#define TK_NULLS                264
+#define TK_ABORT                265
+#define TK_AFTER                266
+#define TK_ATTACH               267
+#define TK_BEFORE               268
+#define TK_BEGIN                269
+#define TK_BITAND               270
+#define TK_BITNOT               271
+#define TK_BITOR                272
+#define TK_BLOCKS               273
+#define TK_CHANGE               274
+#define TK_COMMA                275
+#define TK_COMPACT              276
+#define TK_CONCAT               277
+#define TK_CONFLICT             278
+#define TK_COPY                 279
+#define TK_DEFERRED             280
+#define TK_DELIMITERS           281
+#define TK_DETACH               282
+#define TK_DIVIDE               283
+#define TK_DOT                  284
+#define TK_EACH                 285
+#define TK_FAIL                 286
+#define TK_FILE                 287
+#define TK_FOR                  288
+#define TK_GLOB                 289
+#define TK_ID                   290
+#define TK_IMMEDIATE            291
+#define TK_IMPORT               292
+#define TK_INITIALLY            293
+#define TK_INSTEAD              294
+#define TK_ISNULL               295
+#define TK_KEY                  296
+#define TK_NK_BITNOT            297
+#define TK_NK_SEMI              298
+#define TK_NOTNULL              299
+#define TK_OF                   300
+#define TK_PLUS                 301
+#define TK_PRIVILEGE            302
+#define TK_RAISE                303
+#define TK_REPLACE              304
+#define TK_RESTRICT             305
+#define TK_ROW                  306
+#define TK_SEMI                 307
+#define TK_STAR                 308
+#define TK_STATEMENT            309
+#define TK_STRING               310
+#define TK_TIMES                311
+#define TK_UPDATE               312
+#define TK_VALUES               313
+#define TK_VARIABLE             314
+#define TK_VIEW                 315
+#define TK_WAL                  316
 
 #define TK_NK_SPACE   300
 #define TK_NK_COMMENT 301

include/libs/function/functionMgt.h

@@ -120,6 +120,7 @@ typedef enum EFunctionType {
   FUNCTION_TYPE_WEND,
   FUNCTION_TYPE_WDURATION,
   FUNCTION_TYPE_IROWTS,
+  FUNCTION_TYPE_TAGS,
 
   // internal function
   FUNCTION_TYPE_SELECT_VALUE = 3750,

include/libs/nodes/nodes.h

@@ -27,9 +27,10 @@ extern "C" {
 
 #define LIST_LENGTH(l) (NULL != (l) ? (l)->length : 0)
 
-#define FOREACH(node, list)                                               \
-  for (SListCell *cell = (NULL != (list) ? (list)->pHead : NULL), *pNext; \
-       (NULL != cell ? (node = cell->pNode, pNext = cell->pNext, true) : (node = NULL, pNext = NULL, false)); cell = pNext)
+#define FOREACH(node, list)                                                                                   \
+  for (SListCell* cell = (NULL != (list) ? (list)->pHead : NULL), *pNext;                                     \
+       (NULL != cell ? (node = cell->pNode, pNext = cell->pNext, true) : (node = NULL, pNext = NULL, false)); \
+       cell = pNext)
 
 #define REPLACE_NODE(newNode) cell->pNode = (SNode*)(newNode)
 
@@ -192,6 +193,7 @@ typedef enum ENodeType {
   QUERY_NODE_SHOW_TABLE_DISTRIBUTED_STMT,
   QUERY_NODE_SHOW_LOCAL_VARIABLES_STMT,
   QUERY_NODE_SHOW_SCORES_STMT,
+  QUERY_NODE_SHOW_TABLE_TAGS_STMT,
   QUERY_NODE_KILL_CONNECTION_STMT,
   QUERY_NODE_KILL_QUERY_STMT,
   QUERY_NODE_KILL_TRANSACTION_STMT,

include/libs/sync/sync.h

@@ -132,7 +132,7 @@ typedef struct SSyncFSM {
   void (*FpRollBackCb)(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SFsmCbMeta cbMeta);
 
   void (*FpRestoreFinishCb)(struct SSyncFSM* pFsm);
-  void (*FpReConfigCb)(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta cbMeta);
+  void (*FpReConfigCb)(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta *cbMeta);
   void (*FpLeaderTransferCb)(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SFsmCbMeta cbMeta);
 
   void (*FpBecomeLeaderCb)(struct SSyncFSM* pFsm);

include/util/taoserror.h

@@ -565,6 +565,7 @@ int32_t* taosGetErrno();
 #define TSDB_CODE_PAR_GET_META_ERROR            TAOS_DEF_ERROR_CODE(0, 0x2662)
 #define TSDB_CODE_PAR_NOT_UNIQUE_TABLE_ALIAS    TAOS_DEF_ERROR_CODE(0, 0x2663)
 #define TSDB_CODE_PAR_NOT_SUPPORT_JOIN          TAOS_DEF_ERROR_CODE(0, 0x2664)
+#define TSDB_CODE_PAR_INVALID_TAGS_PC           TAOS_DEF_ERROR_CODE(0, 0x2665)
 #define TSDB_CODE_PAR_INTERNAL_ERROR            TAOS_DEF_ERROR_CODE(0, 0x26FF)
 
 //planner

packaging/release.sh

@@ -219,12 +219,12 @@ fi
 if [[ "$cpuType" == "x64" ]] || [[ "$cpuType" == "aarch64" ]] || [[ "$cpuType" == "aarch32" ]] || [[ "$cpuType" == "arm64" ]] || [[ "$cpuType" == "arm32" ]] || [[ "$cpuType" == "mips64" ]]; then
   if [ "$verMode" != "cluster" ]; then
     # community-version compile
-    cmake ../ -DCPUTYPE=${cpuType} -DOSTYPE=${osType} -DSOMODE=${soMode} -DDBNAME=${dbName} -DVERTYPE=${verType} -DVERDATE="${build_time}" -DGITINFO=${gitinfo} -DGITINFOI=${gitinfoOfInternal} -DVERNUMBER=${verNumber} -DVERCOMPATIBLE=${verNumberComp} -DPAGMODE=${pagMode} -DBUILD_HTTP=${BUILD_HTTP} -DBUILD_TOOLS=${BUILD_TOOLS} ${allocator_macro}
+    cmake ../ -DCPUTYPE=${cpuType} -DWEBSOCKET=true -DOSTYPE=${osType} -DSOMODE=${soMode} -DDBNAME=${dbName} -DVERTYPE=${verType} -DVERDATE="${build_time}" -DGITINFO=${gitinfo} -DGITINFOI=${gitinfoOfInternal} -DVERNUMBER=${verNumber} -DVERCOMPATIBLE=${verNumberComp} -DPAGMODE=${pagMode} -DBUILD_HTTP=${BUILD_HTTP} -DBUILD_TOOLS=${BUILD_TOOLS} ${allocator_macro}
   else
     if [[ "$dbName" != "taos" ]]; then
       replace_enterprise_$dbName
     fi
-    cmake ../../ -DCPUTYPE=${cpuType} -DOSTYPE=${osType} -DSOMODE=${soMode} -DDBNAME=${dbName} -DVERTYPE=${verType} -DVERDATE="${build_time}" -DGITINFO=${gitinfo} -DGITINFOI=${gitinfoOfInternal} -DVERNUMBER=${verNumber} -DVERCOMPATIBLE=${verNumberComp} -DBUILD_HTTP=${BUILD_HTTP} -DBUILD_TOOLS=${BUILD_TOOLS} ${allocator_macro}
+    cmake ../../ -DCPUTYPE=${cpuType} -DWEBSOCKET=true -DOSTYPE=${osType} -DSOMODE=${soMode} -DDBNAME=${dbName} -DVERTYPE=${verType} -DVERDATE="${build_time}" -DGITINFO=${gitinfo} -DGITINFOI=${gitinfoOfInternal} -DVERNUMBER=${verNumber} -DVERCOMPATIBLE=${verNumberComp} -DBUILD_HTTP=${BUILD_HTTP} -DBUILD_TOOLS=${BUILD_TOOLS} ${allocator_macro}
   fi
 else
   echo "input cpuType=${cpuType} error!!!"

source/client/src/clientImpl.c

@@ -874,8 +874,6 @@ void schedulerExecCb(SExecResult* pResult, void* param, int32_t code) {
   STscObj* pTscObj = pRequest->pTscObj;
 
   pRequest->code = code;
-  pRequest->metric.resultReady = taosGetTimestampUs();
-
   if (pResult) {
     destroyQueryExecRes(&pRequest->body.resInfo.execRes);
     memcpy(&pRequest->body.resInfo.execRes, pResult, sizeof(*pResult));
@@ -1061,7 +1059,6 @@ void launchAsyncQuery(SRequestObj* pRequest, SQuery* pQuery, SMetaData* pResultM
       }
 
       pRequest->metric.planEnd = taosGetTimestampUs();
-
       if (TSDB_CODE_SUCCESS == code && !pRequest->validateOnly) {
         SArray* pNodeList = NULL;
         buildAsyncExecNodeList(pRequest, &pNodeList, pMnodeList, pResultMeta);

source/client/src/clientMain.c

@@ -817,7 +817,6 @@ void doAsyncQuery(SRequestObj *pRequest, bool updateMetaForce) {
   pRequest->metric.syntaxEnd = taosGetTimestampUs();
 
   if (!updateMetaForce) {
-    STscObj            *pTscObj = pRequest->pTscObj;
     SAppClusterSummary *pActivity = &pTscObj->pAppInfo->summary;
     if (NULL == pRequest->pQuery->pRoot) {
       atomic_add_fetch_64((int64_t *)&pActivity->numOfInsertsReq, 1);
@@ -864,6 +863,7 @@ static void fetchCallback(void *pResult, void *param, int32_t code) {
   SRequestObj *pRequest = (SRequestObj *)param;
 
   SReqResultInfo *pResultInfo = &pRequest->body.resInfo;
+  pRequest->metric.resultReady = taosGetTimestampUs();
 
   tscDebug("0x%" PRIx64 " enter scheduler fetch cb, code:%d - %s, reqId:0x%" PRIx64, pRequest->self, code,
            tstrerror(code), pRequest->requestId);

source/dnode/mgmt/node_mgmt/src/dmProc.c

@@ -74,11 +74,14 @@ static SProcQueue *dmInitProcQueue(SProc *proc, char *ptr, int32_t size) {
     }
 
     tstrncpy(queue->name, proc->name, sizeof(queue->name));
+
+    taosThreadMutexLock(&queue->mutex);
     queue->head = 0;
     queue->tail = 0;
     queue->total = bufSize;
     queue->avail = bufSize;
     queue->items = 0;
+    taosThreadMutexUnlock(&queue->mutex);
   }
 
   return queue;

source/dnode/mgmt/node_mgmt/src/dmTransport.c

@@ -301,7 +301,7 @@ int32_t dmInitServer(SDnode *pDnode) {
   SDnodeTrans *pTrans = &pDnode->trans;
 
   SRpcInit rpcInit = {0};
-  strncpy(rpcInit.localFqdn, tsLocalFqdn, TSDB_FQDN_LEN);
+  tstrncpy(rpcInit.localFqdn, tsLocalFqdn, TSDB_FQDN_LEN);
   rpcInit.localPort = tsServerPort;
   rpcInit.label = "DND-S";
   rpcInit.numOfThreads = tsNumOfRpcThreads;

source/dnode/mnode/impl/src/mndAcct.c

@@ -83,6 +83,7 @@ static int32_t mndCreateDefaultAcct(SMnode *pMnode) {
 
   STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_NOTHING, NULL, "create-acct");
   if (pTrans == NULL) {
+    sdbFreeRaw(pRaw);
     mError("acct:%s, failed to create since %s", acctObj.acct, terrstr());
     return -1;
   }

source/dnode/mnode/impl/src/mndCluster.c

@@ -315,7 +315,7 @@ static int32_t mndProcessUptimeTimer(SRpcMsg *pReq) {
     return 0;
   }
 
-  mInfo("update cluster uptime to %" PRId64, clusterObj.upTime);
+  mInfo("update cluster uptime to %d", clusterObj.upTime);
   STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_ROLLBACK, TRN_CONFLICT_NOTHING, pReq, "update-uptime");
   if (pTrans == NULL) return -1;
 

source/dnode/mnode/impl/src/mndSync.c

@@ -68,7 +68,7 @@ void mndSyncCommitMsg(struct SSyncFSM *pFsm, const SRpcMsg *pMsg, SFsmCbMeta cbM
     if (pMgmt->errCode != 0) {
       mError("trans:%d, failed to propose since %s, post sem", transId, tstrerror(pMgmt->errCode));
     } else {
-      mInfo("trans:%d, is proposed and post sem", transId, tstrerror(pMgmt->errCode));
+      mInfo("trans:%d, is proposed and post sem", transId);
     }
     pMgmt->transId = 0;
     taosWUnLockLatch(&pMgmt->lock);
@@ -113,13 +113,13 @@ void mndRestoreFinish(struct SSyncFSM *pFsm) {
   }
 }
 
-void mndReConfig(struct SSyncFSM *pFsm, const SRpcMsg *pMsg, SReConfigCbMeta cbMeta) {
+void mndReConfig(struct SSyncFSM *pFsm, const SRpcMsg *pMsg, SReConfigCbMeta *cbMeta) {
   SMnode    *pMnode = pFsm->data;
   SSyncMgmt *pMgmt = &pMnode->syncMgmt;
 
-  pMgmt->errCode = cbMeta.code;
+  pMgmt->errCode = cbMeta->code;
   mInfo("trans:-1, sync reconfig is proposed, saved:%d code:0x%x, index:%" PRId64 " term:%" PRId64, pMgmt->transId,
-        cbMeta.code, cbMeta.index, cbMeta.term);
+        cbMeta->code, cbMeta->index, cbMeta->term);
 
   taosWLockLatch(&pMgmt->lock);
   if (pMgmt->transId == -1) {
@@ -127,7 +127,7 @@ void mndReConfig(struct SSyncFSM *pFsm, const SRpcMsg *pMsg, SReConfigCbMeta cbM
       mError("trans:-1, failed to propose sync reconfig since %s, post sem", tstrerror(pMgmt->errCode));
     } else {
       mInfo("trans:-1, sync reconfig is proposed, saved:%d code:0x%x, index:%" PRId64 " term:%" PRId64 " post sem",
-            pMgmt->transId, cbMeta.code, cbMeta.index, cbMeta.term);
+            pMgmt->transId, cbMeta->code, cbMeta->index, cbMeta->term);
     }
     pMgmt->transId = 0;
     tsem_post(&pMgmt->syncSem);
@@ -271,6 +271,11 @@ void mndCleanupSync(SMnode *pMnode) {
 int32_t mndSyncPropose(SMnode *pMnode, SSdbRaw *pRaw, int32_t transId) {
   SSyncMgmt *pMgmt = &pMnode->syncMgmt;
   SRpcMsg    req = {.msgType = TDMT_MND_APPLY_MSG, .contLen = sdbGetRawTotalSize(pRaw)};
+  if (req.contLen <= 0) {
+    terrno = TSDB_CODE_APP_ERROR;
+    return -1;
+  }
+
   req.pCont = rpcMallocCont(req.contLen);
   if (req.pCont == NULL) return -1;
   memcpy(req.pCont, pRaw, req.contLen);
@@ -278,7 +283,7 @@ int32_t mndSyncPropose(SMnode *pMnode, SSdbRaw *pRaw, int32_t transId) {
   pMgmt->errCode = 0;
   taosWLockLatch(&pMgmt->lock);
   if (pMgmt->transId != 0) {
-    mError("trans:%d, can't be proposed since trans:%s alrady waiting for confirm", transId, pMgmt->transId);
+    mError("trans:%d, can't be proposed since trans:%d alrady waiting for confirm", transId, pMgmt->transId);
     taosWUnLockLatch(&pMgmt->lock);
     terrno = TSDB_CODE_APP_NOT_READY;
     return -1;

source/dnode/mnode/impl/src/mndTopic.c

@@ -776,7 +776,7 @@ static int32_t mndRetrieveTopic(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *pBl
     SName            n;
     int32_t          cols = 0;
 
-    char topicName[TSDB_TOPIC_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
+    char topicName[TSDB_TOPIC_NAME_LEN + VARSTR_HEADER_SIZE + 5] = {0};
     strcpy(varDataVal(topicName), mndGetDbStr(pTopic->name));
     /*tNameFromString(&n, pTopic->name, T_NAME_ACCT | T_NAME_DB);*/
     /*tNameGetDbName(&n, varDataVal(topicName));*/

source/dnode/mnode/impl/src/mndTrans.c

@@ -427,7 +427,7 @@ static SSdbRow *mndTransActionDecode(SSdbRaw *pRaw) {
   terrno = 0;
 
 _OVER:
-  if (terrno != 0) {
+  if (terrno != 0 && pTrans != NULL) {
     mError("trans:%d, failed to parse from raw:%p since %s", pTrans->id, pRaw, terrstr());
     mndTransDropData(pTrans);
     taosMemoryFreeClear(pRow);
@@ -629,6 +629,7 @@ STrans *mndTransCreate(SMnode *pMnode, ETrnPolicy policy, ETrnConflct conflict,
       pTrans->pRpcArray == NULL) {
     terrno = TSDB_CODE_OUT_OF_MEMORY;
     mError("failed to create transaction since %s", terrstr());
+    mndTransDrop(pTrans);
     return NULL;
   }
 
@@ -1428,6 +1429,7 @@ static bool mndTransPerfromFinishedStage(SMnode *pMnode, STrans *pTrans) {
   SSdbRaw *pRaw = mndTransActionEncode(pTrans);
   if (pRaw == NULL) {
     mError("trans:%d, failed to encode while finish trans since %s", pTrans->id, terrstr());
+    return false;
   }
   sdbSetRawStatus(pRaw, SDB_STATUS_DROPPED);
 
@@ -1617,7 +1619,7 @@ static int32_t mndRetrieveTrans(SRpcMsg *pReq, SShowObj *pShow, SSDataBlock *pBl
     colDataAppend(pColInfo, numOfRows, (const char *)&pTrans->lastExecTime, false);
 
     char    lastInfo[TSDB_TRANS_ERROR_LEN + VARSTR_HEADER_SIZE] = {0};
-    char    detail[TSDB_TRANS_ERROR_LEN] = {0};
+    char    detail[TSDB_TRANS_ERROR_LEN + 1] = {0};
     int32_t len = snprintf(detail, sizeof(detail), "action:%d code:0x%x(%s) ", pTrans->lastAction,
                            pTrans->lastErrorNo & 0xFFFF, tstrerror(pTrans->lastErrorNo));
     SEpSet  epset = pTrans->lastEpset;

source/dnode/mnode/impl/src/mndUser.c

@@ -83,6 +83,7 @@ static int32_t mndCreateDefaultUser(SMnode *pMnode, char *acct, char *user, char
 
   STrans *pTrans = mndTransCreate(pMnode, TRN_POLICY_RETRY, TRN_CONFLICT_NOTHING, NULL, "create-user");
   if (pTrans == NULL) {
+    sdbFreeRaw(pRaw);
     mError("user:%s, failed to create since %s", userObj.user, terrstr());
     return -1;
   }

source/dnode/mnode/impl/src/mndVgroup.c

@@ -1250,7 +1250,7 @@ static int32_t mndRedistributeVgroup(SMnode *pMnode, SRpcMsg *pReq, SDbObj *pDb,
       mError("db:%s, vgId:%d, no enough memory:%" PRId64 " in dnode:%d avail:%" PRId64 " used:%" PRId64,
              pVgroup->dbName, pVgroup->vgId, vgMem, pNew1->id, pNew1->memAvail, pNew1->memUsed);
       terrno = TSDB_CODE_MND_NO_ENOUGH_MEM_IN_DNODE;
-      return -1;
+      goto _OVER;
     } else {
       pNew1->memUsed += vgMem;
     }
@@ -1272,7 +1272,7 @@ static int32_t mndRedistributeVgroup(SMnode *pMnode, SRpcMsg *pReq, SDbObj *pDb,
       mError("db:%s, vgId:%d, no enough memory:%" PRId64 " in dnode:%d avail:%" PRId64 " used:%" PRId64,
              pVgroup->dbName, pVgroup->vgId, vgMem, pNew2->id, pNew2->memAvail, pNew2->memUsed);
       terrno = TSDB_CODE_MND_NO_ENOUGH_MEM_IN_DNODE;
-      return -1;
+      goto _OVER;
     } else {
       pNew2->memUsed += vgMem;
     }
@@ -1293,7 +1293,7 @@ static int32_t mndRedistributeVgroup(SMnode *pMnode, SRpcMsg *pReq, SDbObj *pDb,
       mError("db:%s, vgId:%d, no enough memory:%" PRId64 " in dnode:%d avail:%" PRId64 " used:%" PRId64,
              pVgroup->dbName, pVgroup->vgId, vgMem, pNew3->id, pNew3->memAvail, pNew3->memUsed);
       terrno = TSDB_CODE_MND_NO_ENOUGH_MEM_IN_DNODE;
-      return -1;
+     goto _OVER;
     } else {
       pNew3->memUsed += vgMem;
     }
@@ -1627,7 +1627,7 @@ static int32_t mndSplitVgroup(SMnode *pMnode, SRpcMsg *pReq, SDbObj *pDb, SVgObj
   } else if (newVg1.replica == 3) {
     SVnodeGid del1 = {0};
     if (mndRemoveVnodeFromVgroup(pMnode, &newVg1, pArray, &del1) != 0) goto _OVER;
-    if (mndAddSetVnodeStandByAction(pMnode, pTrans, pDb, pVgroup, &del1, true) != 0) return -1;
+    if (mndAddSetVnodeStandByAction(pMnode, pTrans, pDb, pVgroup, &del1, true) != 0) goto _OVER;
     if (mndAddAlterVnodeAction(pMnode, pTrans, pDb, &newVg1, TDMT_VND_ALTER_REPLICA) != 0) goto _OVER;
     if (mndAddDropVnodeAction(pMnode, pTrans, pDb, &newVg1, &del1, true) != 0) goto _OVER;
     if (mndAddAlterVnodeConfirmAction(pMnode, pTrans, pDb, &newVg1) != 0) goto _OVER;

source/dnode/vnode/inc/vnode.h

@@ -92,6 +92,7 @@ typedef struct SMetaEntry  SMetaEntry;
 void        metaReaderInit(SMetaReader *pReader, SMeta *pMeta, int32_t flags);
 void        metaReaderClear(SMetaReader *pReader);
 int32_t     metaGetTableEntryByUid(SMetaReader *pReader, tb_uid_t uid);
+int         metaGetTableEntryByName(SMetaReader *pReader, const char *name);
 int32_t     metaGetTableTags(SMeta *pMeta, uint64_t suid, SArray *uidList, SHashObj *tags);
 int32_t     metaReadNext(SMetaReader *pReader);
 const void *metaGetTableTagVal(void *tag, int16_t type, STagVal *tagVal);

source/dnode/vnode/src/inc/vnodeInt.h

@@ -110,7 +110,6 @@ int             metaAlterTable(SMeta* pMeta, int64_t version, SVAlterTbReq* pReq
 SSchemaWrapper* metaGetTableSchema(SMeta* pMeta, tb_uid_t uid, int32_t sver, bool isinline);
 STSchema*       metaGetTbTSchema(SMeta* pMeta, tb_uid_t uid, int32_t sver);
 int32_t         metaGetTbTSchemaEx(SMeta* pMeta, tb_uid_t suid, tb_uid_t uid, int32_t sver, STSchema** ppTSchema);
-int             metaGetTableEntryByName(SMetaReader* pReader, const char* name);
 tb_uid_t        metaGetTableEntryUidByName(SMeta* pMeta, const char* name);
 int64_t         metaGetTbNum(SMeta* pMeta);
 int64_t         metaGetTimeSeriesNum(SMeta* pMeta);

source/dnode/vnode/src/vnd/vnodeSync.c

@@ -496,16 +496,16 @@ static int32_t vnodeSyncGetSnapshot(SSyncFSM *pFsm, SSnapshot *pSnapshot) {
   return 0;
 }
 
-static void vnodeSyncReconfig(struct SSyncFSM *pFsm, const SRpcMsg *pMsg, SReConfigCbMeta cbMeta) {
+static void vnodeSyncReconfig(struct SSyncFSM *pFsm, const SRpcMsg *pMsg, SReConfigCbMeta *cbMeta) {
   SVnode *pVnode = pFsm->data;
 
   SRpcMsg rpcMsg = {.msgType = pMsg->msgType, .contLen = pMsg->contLen};
-  syncGetAndDelRespRpc(pVnode->sync, cbMeta.newCfgSeqNum, &rpcMsg.info);
-  rpcMsg.info.conn.applyIndex = cbMeta.index;
+  syncGetAndDelRespRpc(pVnode->sync, cbMeta->newCfgSeqNum, &rpcMsg.info);
+  rpcMsg.info.conn.applyIndex = cbMeta->index;
 
   const STraceId *trace = (STraceId *)&pMsg->info.traceId;
   vGTrace("vgId:%d, alter vnode replica is confirmed, type:%s contLen:%d seq:%" PRIu64 " handle:%p", TD_VID(pVnode),
-          TMSG_INFO(pMsg->msgType), pMsg->contLen, cbMeta.seqNum, rpcMsg.info.handle);
+          TMSG_INFO(pMsg->msgType), pMsg->contLen, cbMeta->seqNum, rpcMsg.info.handle);
   if (rpcMsg.info.handle != NULL) {
     tmsgSendRsp(&rpcMsg);
   }

source/libs/catalog/src/ctgAsync.c

@@ -487,6 +487,8 @@ int32_t ctgInitTask(SCtgJob* pJob, CTG_TASK_TYPE type, void* param, int32_t* tas
 int32_t ctgInitJob(SCatalog* pCtg, SRequestConnInfo* pConn, SCtgJob** job, const SCatalogReq* pReq, catalogCallback fp,
                    void* param) {
   int32_t code = 0;
+  int64_t st = taosGetTimestampUs();
+
   int32_t tbMetaNum = (int32_t)ctgGetTablesReqNum(pReq->pTableMeta);
   int32_t dbVgNum = (int32_t)taosArrayGetSize(pReq->pDbVgroup);
   int32_t tbHashNum = (int32_t)ctgGetTablesReqNum(pReq->pTableHash);
@@ -634,12 +636,12 @@ int32_t ctgInitJob(SCatalog* pCtg, SRequestConnInfo* pConn, SCtgJob** job, const
 
   taosAcquireRef(gCtgMgmt.jobPool, pJob->refId);
 
-  qDebug("QID:0x%" PRIx64 ", jobId: 0x%" PRIx64 " initialized, task num %d, forceUpdate %d", pJob->queryId, pJob->refId,
-         taskNum, pReq->forceUpdate);
+  double el = (taosGetTimestampUs() - st)/1000.0;
+  qDebug("QID:0x%" PRIx64 ", jobId: 0x%" PRIx64 " initialized, task num %d, forceUpdate %d, elapsed time:%.2f ms",
+         pJob->queryId, pJob->refId, taskNum, pReq->forceUpdate, el);
   return TSDB_CODE_SUCCESS;
 
 _return:
-
   ctgFreeJob(*job);
   CTG_RET(code);
 }

source/libs/executor/src/executorimpl.c

@@ -1273,6 +1273,14 @@ static void doCopyResultToDataBlock(SExprInfo* pExprInfo, int32_t numOfExprs, SR
 
     pCtx[j].resultInfo = getResultEntryInfo(pRow, j, rowEntryOffset);
     if (pCtx[j].fpSet.finalize) {
+      if (strcmp(pCtx[j].pExpr->pExpr->_function.functionName, "_group_key") == 0) {
+        // for groupkey along with functions that output multiple lines(e.g. Histogram)
+        // need to match groupkey result for each output row of that function.
+        if (pCtx[j].resultInfo->numOfRes != 0) {
+          pCtx[j].resultInfo->numOfRes = pRow->numOfRows;
+        }
+      }
+
       int32_t code = pCtx[j].fpSet.finalize(&pCtx[j], pBlock);
       if (TAOS_FAILED(code)) {
         qError("%s build result data block error, code %s", GET_TASKID(pTaskInfo), tstrerror(code));

source/libs/executor/src/scanoperator.c

@@ -41,7 +41,12 @@ static int32_t buildDbTableInfoBlock(bool sysInfo, const SSDataBlock* p, const S
 
 static bool processBlockWithProbability(const SSampleExecInfo* pInfo);
 
-bool processBlockWithProbability(const SSampleExecInfo* pInfo) {
+static int32_t sysTableUserTagsFillOneTableTags(const SSysTableScanInfo* pInfo, SMetaReader* smr, const char* dbname,
+                                                const char* tableName, int32_t* pNumOfRows,
+                                                const SSDataBlock* dataBlock);
+
+static void relocateAndFilterSysTagsScanResult(SSysTableScanInfo* pInfo, int32_t numOfRows, SSDataBlock* dataBlock);
+bool        processBlockWithProbability(const SSampleExecInfo* pInfo) {
 #if 0
   if (pInfo->sampleRatio == 1) {
     return true;
@@ -2399,6 +2404,48 @@ int32_t convertTagDataToStr(char* str, int type, void* buf, int32_t bufSize, int
   return TSDB_CODE_SUCCESS;
 }
 
+static bool sysTableIsOperatorCondOnOneTable(SNode* pCond, char* condTable) {
+  SOperatorNode* node = (SOperatorNode*)pCond;
+  if (node->opType == OP_TYPE_EQUAL) {
+    if (nodeType(node->pLeft) == QUERY_NODE_COLUMN &&
+        strcasecmp(nodesGetNameFromColumnNode(node->pLeft), "table_name") == 0 &&
+        nodeType(node->pRight) == QUERY_NODE_VALUE) {
+      SValueNode* pValue = (SValueNode*)node->pRight;
+      if (pValue->node.type == TSDB_DATA_TYPE_NCHAR || pValue->node.type == TSDB_DATA_TYPE_VARCHAR ||
+          pValue->node.type == TSDB_DATA_TYPE_BINARY) {
+        char* value = nodesGetStrValueFromNode(pValue);
+        strncpy(condTable, value, TSDB_TABLE_NAME_LEN);
+        taosMemoryFree(value);
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+static bool sysTableIsCondOnOneTable(SNode* pCond, char* condTable) {
+  if (pCond == NULL) {
+    return false;
+  }
+  if (nodeType(pCond) == QUERY_NODE_LOGIC_CONDITION) {
+    SLogicConditionNode* node = (SLogicConditionNode*)pCond;
+    if (LOGIC_COND_TYPE_AND == node->condType) {
+      SNode* pChild = NULL;
+      FOREACH(pChild, node->pParameterList) {
+        if (QUERY_NODE_OPERATOR == nodeType(pChild) && sysTableIsOperatorCondOnOneTable(pChild, condTable)) {
+          return true;
+        }
+      }
+    }
+  }
+
+  if (QUERY_NODE_OPERATOR == nodeType(pCond)) {
+    return sysTableIsOperatorCondOnOneTable(pCond, condTable);
+  }
+
+  return false;
+}
+
 static SSDataBlock* sysTableScanUserTags(SOperatorInfo* pOperator) {
   SExecTaskInfo*     pTaskInfo = pOperator->pTaskInfo;
   SSysTableScanInfo* pInfo = pOperator->info;
@@ -2406,13 +2453,12 @@ static SSDataBlock* sysTableScanUserTags(SOperatorInfo* pOperator) {
     return NULL;
   }
 
-  if (pInfo->pCur == NULL) {
-    pInfo->pCur = metaOpenTbCursor(pInfo->readHandle.meta);
-  }
-
   blockDataCleanup(pInfo->pRes);
   int32_t numOfRows = 0;
 
+  SSDataBlock* dataBlock = buildInfoSchemaTableMetaBlock(TSDB_INS_TABLE_TAGS);
+  blockDataEnsureCapacity(dataBlock, pOperator->resultInfo.capacity);
+
   const char* db = NULL;
   int32_t     vgId = 0;
   vnodeGetInfo(pInfo->readHandle.vnode, &db, &vgId);
@@ -2424,10 +2470,32 @@ static SSDataBlock* sysTableScanUserTags(SOperatorInfo* pOperator) {
   tNameGetDbName(&sn, varDataVal(dbname));
   varDataSetLen(dbname, strlen(varDataVal(dbname)));
 
-  SSDataBlock* p = buildInfoSchemaTableMetaBlock(TSDB_INS_TABLE_TAGS);
-  blockDataEnsureCapacity(p, pOperator->resultInfo.capacity);
+  char condTableName[TSDB_TABLE_NAME_LEN] = {0};
+  // optimize when sql like where table_name='tablename' and xxx.
+  if (pInfo->pCondition && sysTableIsCondOnOneTable(pInfo->pCondition, condTableName)) {
+    char tableName[TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
+    STR_TO_VARSTR(tableName, condTableName);
+
+    SMetaReader smr = {0};
+    metaReaderInit(&smr, pInfo->readHandle.meta, 0);
+    metaGetTableEntryByName(&smr, condTableName);
+    sysTableUserTagsFillOneTableTags(pInfo, &smr, dbname, tableName, &numOfRows, dataBlock);
+    metaReaderClear(&smr);
+    if (numOfRows > 0) {
+      relocateAndFilterSysTagsScanResult(pInfo, numOfRows, dataBlock);
+      numOfRows = 0;
+    }
+    blockDataDestroy(dataBlock);
+
+    pInfo->loadInfo.totalRows += pInfo->pRes->info.rows;
+    return (pInfo->pRes->info.rows == 0) ? NULL : pInfo->pRes;
+  }
 
   int32_t ret = 0;
+  if (pInfo->pCur == NULL) {
+    pInfo->pCur = metaOpenTbCursor(pInfo->readHandle.meta);
+  }
+
   while ((ret = metaTbCursorNext(pInfo->pCur)) == 0) {
     if (pInfo->pCur->mr.me.type != TSDB_CHILD_TABLE) {
       continue;
@@ -2450,100 +2518,12 @@ static SSDataBlock* sysTableScanUserTags(SOperatorInfo* pOperator) {
       T_LONG_JMP(pTaskInfo->env, terrno);
     }
 
-    char stableName[TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
-    STR_TO_VARSTR(stableName, smr.me.name);
-
-    int32_t numOfTags = smr.me.stbEntry.schemaTag.nCols;
-    for (int32_t i = 0; i < numOfTags; ++i) {
-      SColumnInfoData* pColInfoData = NULL;
-
-      // table name
-      pColInfoData = taosArrayGet(p->pDataBlock, 0);
-      colDataAppend(pColInfoData, numOfRows, tableName, false);
-
-      // database name
-      pColInfoData = taosArrayGet(p->pDataBlock, 1);
-      colDataAppend(pColInfoData, numOfRows, dbname, false);
-
-      // super table name
-      pColInfoData = taosArrayGet(p->pDataBlock, 2);
-      colDataAppend(pColInfoData, numOfRows, stableName, false);
-
-      // tag name
-      char tagName[TSDB_COL_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
-      STR_TO_VARSTR(tagName, smr.me.stbEntry.schemaTag.pSchema[i].name);
-      pColInfoData = taosArrayGet(p->pDataBlock, 3);
-      colDataAppend(pColInfoData, numOfRows, tagName, false);
-
-      // tag type
-      int8_t tagType = smr.me.stbEntry.schemaTag.pSchema[i].type;
-      pColInfoData = taosArrayGet(p->pDataBlock, 4);
-      char tagTypeStr[VARSTR_HEADER_SIZE + 32];
-      int  tagTypeLen = sprintf(varDataVal(tagTypeStr), "%s", tDataTypes[tagType].name);
-      if (tagType == TSDB_DATA_TYPE_VARCHAR) {
-        tagTypeLen += sprintf(varDataVal(tagTypeStr) + tagTypeLen, "(%d)",
-                              (int32_t)(smr.me.stbEntry.schemaTag.pSchema[i].bytes - VARSTR_HEADER_SIZE));
-      } else if (tagType == TSDB_DATA_TYPE_NCHAR) {
-        tagTypeLen +=
-            sprintf(varDataVal(tagTypeStr) + tagTypeLen, "(%d)",
-                    (int32_t)((smr.me.stbEntry.schemaTag.pSchema[i].bytes - VARSTR_HEADER_SIZE) / TSDB_NCHAR_SIZE));
-      }
-      varDataSetLen(tagTypeStr, tagTypeLen);
-      colDataAppend(pColInfoData, numOfRows, (char*)tagTypeStr, false);
-
-      STagVal tagVal = {0};
-      tagVal.cid = smr.me.stbEntry.schemaTag.pSchema[i].colId;
-      char*    tagData = NULL;
-      uint32_t tagLen = 0;
+    sysTableUserTagsFillOneTableTags(pInfo, &smr, dbname, tableName, &numOfRows, dataBlock);
 
-      if (tagType == TSDB_DATA_TYPE_JSON) {
-        tagData = (char*)pInfo->pCur->mr.me.ctbEntry.pTags;
-      } else {
-        bool exist = tTagGet((STag*)pInfo->pCur->mr.me.ctbEntry.pTags, &tagVal);
-        if (exist) {
-          if (IS_VAR_DATA_TYPE(tagType)) {
-            tagData = (char*)tagVal.pData;
-            tagLen = tagVal.nData;
-          } else {
-            tagData = (char*)&tagVal.i64;
-            tagLen = tDataTypes[tagType].bytes;
-          }
-        }
-      }
-
-      char* tagVarChar = NULL;
-      if (tagData != NULL) {
-        if (tagType == TSDB_DATA_TYPE_JSON) {
-          char* tagJson = parseTagDatatoJson(tagData);
-          tagVarChar = taosMemoryMalloc(strlen(tagJson) + VARSTR_HEADER_SIZE);
-          memcpy(varDataVal(tagVarChar), tagJson, strlen(tagJson));
-          varDataSetLen(tagVarChar, strlen(tagJson));
-          taosMemoryFree(tagJson);
-        } else {
-          int32_t bufSize = IS_VAR_DATA_TYPE(tagType) ? (tagLen + VARSTR_HEADER_SIZE)
-                                                      : (3 + DBL_MANT_DIG - DBL_MIN_EXP + VARSTR_HEADER_SIZE);
-          tagVarChar = taosMemoryMalloc(bufSize);
-          int32_t len = -1;
-          convertTagDataToStr(varDataVal(tagVarChar), tagType, tagData, tagLen, &len);
-          varDataSetLen(tagVarChar, len);
-        }
-      }
-      pColInfoData = taosArrayGet(p->pDataBlock, 5);
-      colDataAppend(pColInfoData, numOfRows, tagVarChar,
-                    (tagData == NULL) || (tagType == TSDB_DATA_TYPE_JSON && tTagIsJsonNull(tagData)));
-      taosMemoryFree(tagVarChar);
-      ++numOfRows;
-    }
     metaReaderClear(&smr);
 
     if (numOfRows >= pOperator->resultInfo.capacity) {
-      p->info.rows = numOfRows;
-      pInfo->pRes->info.rows = numOfRows;
-
-      relocateColumnData(pInfo->pRes, pInfo->scanCols, p->pDataBlock, false);
-      doFilterResult(pInfo);
-
-      blockDataCleanup(p);
+      relocateAndFilterSysTagsScanResult(pInfo, numOfRows, dataBlock);
       numOfRows = 0;
 
       if (pInfo->pRes->info.rows > 0) {
@@ -2553,19 +2533,11 @@ static SSDataBlock* sysTableScanUserTags(SOperatorInfo* pOperator) {
   }
 
   if (numOfRows > 0) {
-    p->info.rows = numOfRows;
-    pInfo->pRes->info.rows = numOfRows;
-
-    relocateColumnData(pInfo->pRes, pInfo->scanCols, p->pDataBlock, false);
-    doFilterResult(pInfo);
-
-    blockDataCleanup(p);
+    relocateAndFilterSysTagsScanResult(pInfo, numOfRows, dataBlock);
     numOfRows = 0;
   }
 
-  blockDataDestroy(p);
-
-  // todo temporarily free the cursor here, the true reason why the free is not valid needs to be found
+  blockDataDestroy(dataBlock);
   if (ret != 0) {
     metaCloseTbCursor(pInfo->pCur);
     pInfo->pCur = NULL;
@@ -2576,6 +2548,111 @@ static SSDataBlock* sysTableScanUserTags(SOperatorInfo* pOperator) {
   return (pInfo->pRes->info.rows == 0) ? NULL : pInfo->pRes;
 }
 
+static void relocateAndFilterSysTagsScanResult(SSysTableScanInfo* pInfo, int32_t numOfRows, SSDataBlock* dataBlock) {
+  dataBlock->info.rows = numOfRows;
+  pInfo->pRes->info.rows = numOfRows;
+
+  relocateColumnData(pInfo->pRes, pInfo->scanCols, dataBlock->pDataBlock, false);
+  doFilterResult(pInfo);
+
+  blockDataCleanup(dataBlock);
+}
+
+static int32_t sysTableUserTagsFillOneTableTags(const SSysTableScanInfo* pInfo, SMetaReader* smr, const char* dbname,
+                                                const char* tableName, int32_t* pNumOfRows,
+                                                const SSDataBlock* dataBlock) {
+  char stableName[TSDB_TABLE_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
+  STR_TO_VARSTR(stableName, (*smr).me.name);
+
+  int32_t numOfRows = *pNumOfRows;
+
+  int32_t numOfTags = (*smr).me.stbEntry.schemaTag.nCols;
+  for (int32_t i = 0; i < numOfTags; ++i) {
+    SColumnInfoData* pColInfoData = NULL;
+
+    // table name
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 0);
+    colDataAppend(pColInfoData, numOfRows, tableName, false);
+
+    // database name
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 1);
+    colDataAppend(pColInfoData, numOfRows, dbname, false);
+
+    // super table name
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 2);
+    colDataAppend(pColInfoData, numOfRows, stableName, false);
+
+    // tag name
+    char tagName[TSDB_COL_NAME_LEN + VARSTR_HEADER_SIZE] = {0};
+    STR_TO_VARSTR(tagName, (*smr).me.stbEntry.schemaTag.pSchema[i].name);
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 3);
+    colDataAppend(pColInfoData, numOfRows, tagName, false);
+
+    // tag type
+    int8_t tagType = (*smr).me.stbEntry.schemaTag.pSchema[i].type;
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 4);
+    char tagTypeStr[VARSTR_HEADER_SIZE + 32];
+    int  tagTypeLen = sprintf(varDataVal(tagTypeStr), "%s", tDataTypes[tagType].name);
+    if (tagType == TSDB_DATA_TYPE_VARCHAR) {
+      tagTypeLen += sprintf(varDataVal(tagTypeStr) + tagTypeLen, "(%d)",
+                            (int32_t)((*smr).me.stbEntry.schemaTag.pSchema[i].bytes - VARSTR_HEADER_SIZE));
+    } else if (tagType == TSDB_DATA_TYPE_NCHAR) {
+      tagTypeLen +=
+          sprintf(varDataVal(tagTypeStr) + tagTypeLen, "(%d)",
+                  (int32_t)(((*smr).me.stbEntry.schemaTag.pSchema[i].bytes - VARSTR_HEADER_SIZE) / TSDB_NCHAR_SIZE));
+    }
+    varDataSetLen(tagTypeStr, tagTypeLen);
+    colDataAppend(pColInfoData, numOfRows, (char*)tagTypeStr, false);
+
+    STagVal tagVal = {0};
+    tagVal.cid = (*smr).me.stbEntry.schemaTag.pSchema[i].colId;
+    char*    tagData = NULL;
+    uint32_t tagLen = 0;
+
+    if (tagType == TSDB_DATA_TYPE_JSON) {
+      tagData = (char*)pInfo->pCur->mr.me.ctbEntry.pTags;
+    } else {
+      bool exist = tTagGet((STag*)pInfo->pCur->mr.me.ctbEntry.pTags, &tagVal);
+      if (exist) {
+        if (IS_VAR_DATA_TYPE(tagType)) {
+          tagData = (char*)tagVal.pData;
+          tagLen = tagVal.nData;
+        } else {
+          tagData = (char*)&tagVal.i64;
+          tagLen = tDataTypes[tagType].bytes;
+        }
+      }
+    }
+
+    char* tagVarChar = NULL;
+    if (tagData != NULL) {
+      if (tagType == TSDB_DATA_TYPE_JSON) {
+        char* tagJson = parseTagDatatoJson(tagData);
+        tagVarChar = taosMemoryMalloc(strlen(tagJson) + VARSTR_HEADER_SIZE);
+        memcpy(varDataVal(tagVarChar), tagJson, strlen(tagJson));
+        varDataSetLen(tagVarChar, strlen(tagJson));
+        taosMemoryFree(tagJson);
+      } else {
+        int32_t bufSize = IS_VAR_DATA_TYPE(tagType) ? (tagLen + VARSTR_HEADER_SIZE)
+                                                    : (3 + DBL_MANT_DIG - DBL_MIN_EXP + VARSTR_HEADER_SIZE);
+        tagVarChar = taosMemoryMalloc(bufSize);
+        int32_t len = -1;
+        convertTagDataToStr(varDataVal(tagVarChar), tagType, tagData, tagLen, &len);
+        varDataSetLen(tagVarChar, len);
+      }
+    }
+    pColInfoData = taosArrayGet(dataBlock->pDataBlock, 5);
+    colDataAppend(pColInfoData, numOfRows, tagVarChar,
+                  (tagData == NULL) || (tagType == TSDB_DATA_TYPE_JSON && tTagIsJsonNull(tagData)));
+    taosMemoryFree(tagVarChar);
+    ++numOfRows;
+  }
+
+  *pNumOfRows = numOfRows;
+
+  return TSDB_CODE_SUCCESS;
+}
+
 static SSDataBlock* sysTableScanUserTables(SOperatorInfo* pOperator) {
   SExecTaskInfo*     pTaskInfo = pOperator->pTaskInfo;
   SSysTableScanInfo* pInfo = pOperator->info;

source/libs/function/src/builtins.c

@@ -2020,6 +2020,11 @@ static int32_t translateUserFunc(SFunctionNode* pFunc, char* pErrBuf, int32_t le
   return TSDB_CODE_SUCCESS;
 }
 
+static int32_t translateTagsPseudoColumn(SFunctionNode* pFunc, char* pErrBuf, int32_t len) {
+  // The _tags pseudo-column will be expanded to the actual tags on the client side
+  return TSDB_CODE_SUCCESS;
+}
+
 // clang-format off
 const SBuiltinFuncDefinition funcMgtBuiltins[] = {
   {
@@ -3156,6 +3161,16 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
     .sprocessFunc = NULL,
     .finalizeFunc = NULL
   },
+  {
+    .name = "_tags",
+    .type = FUNCTION_TYPE_TAGS,
+    .classification = FUNC_MGT_PSEUDO_COLUMN_FUNC | FUNC_MGT_MULTI_RES_FUNC,
+    .translateFunc = translateTagsPseudoColumn,
+    .getEnvFunc   = NULL,
+    .initFunc     = NULL,
+    .sprocessFunc = NULL,
+    .finalizeFunc = NULL
+  },
 };
 // clang-format on
 

source/libs/function/src/builtinsimpl.c

@@ -6157,7 +6157,10 @@ int32_t groupKeyFinalize(SqlFunctionCtx* pCtx, SSDataBlock* pBlock) {
   SGroupKeyInfo* pInfo = GET_ROWCELL_INTERBUF(pResInfo);
 
   if (pInfo->hasResult) {
-    colDataAppend(pCol, pBlock->info.rows, pInfo->data, pInfo->isNull ? true : false);
+    int32_t currentRow = pBlock->info.rows;
+    for (; currentRow < pBlock->info.rows + pResInfo->numOfRes; ++currentRow) {
+      colDataAppend(pCol, currentRow, pInfo->data, pInfo->isNull ? true : false);
+    }
   } else {
     pResInfo->numOfRes = 0;
   }

source/libs/nodes/src/nodesUtilFuncs.c

@@ -419,6 +419,7 @@ SNode* nodesMakeNode(ENodeType type) {
     case QUERY_NODE_SHOW_TRANSACTIONS_STMT:
     case QUERY_NODE_SHOW_SUBSCRIPTIONS_STMT:
     case QUERY_NODE_SHOW_TAGS_STMT:
+    case QUERY_NODE_SHOW_TABLE_TAGS_STMT:
       return makeNode(type, sizeof(SShowStmt));
     case QUERY_NODE_SHOW_DNODE_VARIABLES_STMT:
       return makeNode(type, sizeof(SShowDnodeVariablesStmt));
@@ -921,7 +922,8 @@ void nodesDestroyNode(SNode* pNode) {
     case QUERY_NODE_SHOW_LOCAL_VARIABLES_STMT:
     case QUERY_NODE_SHOW_TRANSACTIONS_STMT:
     case QUERY_NODE_SHOW_SUBSCRIPTIONS_STMT:
-    case QUERY_NODE_SHOW_TAGS_STMT: {
+    case QUERY_NODE_SHOW_TAGS_STMT:
+    case QUERY_NODE_SHOW_TABLE_TAGS_STMT: {
       SShowStmt* pStmt = (SShowStmt*)pNode;
       nodesDestroyNode(pStmt->pDbName);
       nodesDestroyNode(pStmt->pTbName);

source/libs/parser/inc/sql.y

@@ -420,6 +420,7 @@ cmd ::= SHOW TABLE DISTRIBUTED full_table_name(A).
 cmd ::= SHOW CONSUMERS.                                                           { pCxt->pRootNode = createShowStmt(pCxt, QUERY_NODE_SHOW_CONSUMERS_STMT); }
 cmd ::= SHOW SUBSCRIPTIONS.                                                       { pCxt->pRootNode = createShowStmt(pCxt, QUERY_NODE_SHOW_SUBSCRIPTIONS_STMT); }
 cmd ::= SHOW TAGS FROM table_name_cond(A) from_db_opt(B).                         { pCxt->pRootNode = createShowStmtWithCond(pCxt, QUERY_NODE_SHOW_TAGS_STMT, B, A, OP_TYPE_EQUAL); }
+cmd ::= SHOW TABLE TAGS FROM table_name_cond(A) from_db_opt(B).                   { pCxt->pRootNode = createShowStmtWithCond(pCxt, QUERY_NODE_SHOW_TABLE_TAGS_STMT, B, A, OP_TYPE_EQUAL); }
 cmd ::= SHOW VNODES NK_INTEGER(A).                                                { pCxt->pRootNode = createShowVnodesStmt(pCxt, createValueNode(pCxt, TSDB_DATA_TYPE_BIGINT, &A), NULL); }
 cmd ::= SHOW VNODES NK_STRING(A).                                                 { pCxt->pRootNode = createShowVnodesStmt(pCxt, NULL, createValueNode(pCxt, TSDB_DATA_TYPE_VARCHAR, &A)); }
 
@@ -708,6 +709,7 @@ pseudo_column(A) ::= WSTART(B).
 pseudo_column(A) ::= WEND(B).                                                     { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
 pseudo_column(A) ::= WDURATION(B).                                                { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
 pseudo_column(A) ::= IROWTS(B).                                                   { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
+pseudo_column(A) ::= QTAGS(B).                                                    { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
 
 function_expression(A) ::= function_name(B) NK_LP expression_list(C) NK_RP(D).    { A = createRawExprNodeExt(pCxt, &B, &D, createFunctionNode(pCxt, &B, C)); }
 function_expression(A) ::= star_func(B) NK_LP star_func_para_list(C) NK_RP(D).    { A = createRawExprNodeExt(pCxt, &B, &D, createFunctionNode(pCxt, &B, C)); }

source/libs/parser/src/parAstCreater.c

@@ -1310,7 +1310,7 @@ SNode* createUseDatabaseStmt(SAstCreateContext* pCxt, SToken* pDbName) {
 static bool needDbShowStmt(ENodeType type) {
   return QUERY_NODE_SHOW_TABLES_STMT == type || QUERY_NODE_SHOW_STABLES_STMT == type ||
          QUERY_NODE_SHOW_VGROUPS_STMT == type || QUERY_NODE_SHOW_INDEXES_STMT == type ||
-         QUERY_NODE_SHOW_TAGS_STMT == type;
+         QUERY_NODE_SHOW_TAGS_STMT == type || QUERY_NODE_SHOW_TABLE_TAGS_STMT == type;
 }
 
 SNode* createShowStmt(SAstCreateContext* pCxt, ENodeType type) {

source/libs/parser/src/parAstParser.c

@@ -414,6 +414,11 @@ static int32_t collectMetaKeyFromShowTags(SCollectMetaKeyCxt* pCxt, SShowStmt* p
   return code;
 }
 
+static int32_t collectMetaKeyFromShowStableTags(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
+  return collectMetaKeyFromRealTableImpl(pCxt, ((SValueNode*)pStmt->pDbName)->literal,
+                                         ((SValueNode*)pStmt->pTbName)->literal, AUTH_TYPE_READ);
+}
+
 static int32_t collectMetaKeyFromShowUsers(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
   return reserveTableMetaInCache(pCxt->pParseCxt->acctId, TSDB_INFORMATION_SCHEMA_DB, TSDB_INS_TABLE_USERS,
                                  pCxt->pMetaCache);
@@ -595,6 +600,8 @@ static int32_t collectMetaKeyFromQuery(SCollectMetaKeyCxt* pCxt, SNode* pStmt) {
       return collectMetaKeyFromShowTables(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_TAGS_STMT:
       return collectMetaKeyFromShowTags(pCxt, (SShowStmt*)pStmt);
+    case QUERY_NODE_SHOW_TABLE_TAGS_STMT:
+      return collectMetaKeyFromShowStableTags(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_USERS_STMT:
       return collectMetaKeyFromShowUsers(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_LICENCES_STMT:

source/libs/parser/src/parTokenizer.c

@@ -257,6 +257,7 @@ static SKeyword keywordTable[] = {
     {"_QEND",                TK_QEND},
     {"_QSTART",              TK_QSTART},
     {"_ROWTS",               TK_ROWTS},
+    {"_TAGS",                TK_QTAGS},
     {"_WDURATION",           TK_WDURATION},
     {"_WEND",                TK_WEND},
     {"_WSTART",              TK_WSTART},

source/libs/parser/src/parTranslater.c

@@ -1215,6 +1215,9 @@ static bool isMultiResFunc(SNode* pNode) {
   if (QUERY_NODE_FUNCTION != nodeType(pNode) || !fmIsMultiResFunc(((SFunctionNode*)pNode)->funcId)) {
     return false;
   }
+  if (FUNCTION_TYPE_TAGS == ((SFunctionNode*)pNode)->funcType) {
+    return true;
+  }
   SNodeList* pParameterList = ((SFunctionNode*)pNode)->pParameterList;
   if (LIST_LENGTH(pParameterList) > 1) {
     return true;
@@ -1556,7 +1559,7 @@ static int32_t translateMultiResFunc(STranslateContext* pCxt, SFunctionNode* pFu
                                      "%s(*) is only supported in SELECTed list", pFunc->functionName);
     }
   }
-  if (tsKeepColumnName) {
+  if (tsKeepColumnName && 1 == LIST_LENGTH(pFunc->pParameterList)) {
     strcpy(pFunc->node.userAlias, ((SExprNode*)nodesListGetNode(pFunc->pParameterList, 0))->userAlias);
   }
   return TSDB_CODE_SUCCESS;
@@ -1842,17 +1845,46 @@ static EDealRes translateWhenThen(STranslateContext* pCxt, SWhenThenNode* pWhenT
   return DEAL_RES_CONTINUE;
 }
 
+static bool isCondition(const SNode* pNode) {
+  if (QUERY_NODE_OPERATOR == nodeType(pNode)) {
+    return nodesIsComparisonOp((const SOperatorNode*)pNode);
+  }
+  return (QUERY_NODE_LOGIC_CONDITION == nodeType(pNode));
+}
+
+static int32_t rewriteIsTrue(SNode* pSrc, SNode** pIsTrue) {
+  SOperatorNode* pOp = (SOperatorNode*)nodesMakeNode(QUERY_NODE_OPERATOR);
+  if (NULL == pOp) {
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  pOp->opType = OP_TYPE_IS_TRUE;
+  pOp->pLeft = pSrc;
+  pOp->node.resType.type = TSDB_DATA_TYPE_BOOL;
+  pOp->node.resType.bytes = tDataTypes[TSDB_DATA_TYPE_BOOL].bytes;
+  *pIsTrue = (SNode*)pOp;
+  return TSDB_CODE_SUCCESS;
+}
+
 static EDealRes translateCaseWhen(STranslateContext* pCxt, SCaseWhenNode* pCaseWhen) {
   bool   first = true;
   SNode* pNode = NULL;
   FOREACH(pNode, pCaseWhen->pWhenThenList) {
+    SWhenThenNode* pWhenThen = (SWhenThenNode*)pNode;
+    if (NULL == pCaseWhen->pCase && !isCondition(pWhenThen->pWhen)) {
+      SNode* pIsTrue = NULL;
+      pCxt->errCode = rewriteIsTrue(pWhenThen->pWhen, &pIsTrue);
+      if (TSDB_CODE_SUCCESS != pCxt->errCode) {
+        return DEAL_RES_ERROR;
+      }
+      pWhenThen->pWhen = pIsTrue;
+    }
     if (first) {
       pCaseWhen->node.resType = ((SExprNode*)pNode)->resType;
     } else if (!dataTypeEqual(&pCaseWhen->node.resType, &((SExprNode*)pNode)->resType)) {
-      SWhenThenNode* pWhenThen = (SWhenThenNode*)pNode;
-      SNode*         pCastFunc = NULL;
-      if (TSDB_CODE_SUCCESS != createCastFunc(pCxt, pWhenThen->pThen, pCaseWhen->node.resType, &pCastFunc)) {
-        return generateSyntaxErrMsgExt(&pCxt->msgBuf, TSDB_CODE_PAR_WRONG_VALUE_TYPE, "CASE WHEN data type mismatch");
+      SNode* pCastFunc = NULL;
+      pCxt->errCode = createCastFunc(pCxt, pWhenThen->pThen, pCaseWhen->node.resType, &pCastFunc);
+      if (TSDB_CODE_SUCCESS != pCxt->errCode) {
+        return DEAL_RES_ERROR;
       }
       pWhenThen->pThen = pCastFunc;
       pWhenThen->node.resType = pCaseWhen->node.resType;
@@ -1860,8 +1892,9 @@ static EDealRes translateCaseWhen(STranslateContext* pCxt, SCaseWhenNode* pCaseW
   }
   if (NULL != pCaseWhen->pElse && !dataTypeEqual(&pCaseWhen->node.resType, &((SExprNode*)pCaseWhen->pElse)->resType)) {
     SNode* pCastFunc = NULL;
-    if (TSDB_CODE_SUCCESS != createCastFunc(pCxt, pCaseWhen->pElse, pCaseWhen->node.resType, &pCastFunc)) {
-      return generateSyntaxErrMsgExt(&pCxt->msgBuf, TSDB_CODE_PAR_WRONG_VALUE_TYPE, "CASE WHEN data type mismatch");
+    pCxt->errCode = createCastFunc(pCxt, pCaseWhen->pElse, pCaseWhen->node.resType, &pCastFunc);
+    if (TSDB_CODE_SUCCESS != pCxt->errCode) {
+      return DEAL_RES_ERROR;
     }
     pCaseWhen->pElse = pCastFunc;
     ((SExprNode*)pCaseWhen->pElse)->resType = pCaseWhen->node.resType;
@@ -2585,6 +2618,34 @@ static int32_t createMultiResFuncsFromStar(STranslateContext* pCxt, SFunctionNod
   return code;
 }
 
+static int32_t createTags(STranslateContext* pCxt, SNodeList** pOutput) {
+  if (QUERY_NODE_REAL_TABLE != nodeType(((SSelectStmt*)pCxt->pCurrStmt)->pFromTable)) {
+    return generateSyntaxErrMsgExt(&pCxt->msgBuf, TSDB_CODE_PAR_INVALID_TAGS_PC,
+                                   "The _TAGS pseudo column can only be used for subtable and supertable queries");
+  }
+
+  SRealTableNode*   pTable = (SRealTableNode*)(((SSelectStmt*)pCxt->pCurrStmt)->pFromTable);
+  const STableMeta* pMeta = pTable->pMeta;
+  if (TSDB_SUPER_TABLE != pMeta->tableType && TSDB_CHILD_TABLE != pMeta->tableType) {
+    return generateSyntaxErrMsg(&pCxt->msgBuf, TSDB_CODE_PAR_INVALID_TAGS_PC,
+                                "The _TAGS pseudo column can only be used for subtable and supertable queries");
+  }
+
+  SSchema* pTagsSchema = getTableTagSchema(pMeta);
+  for (int32_t i = 0; i < pMeta->tableInfo.numOfTags; ++i) {
+    SColumnNode* pCol = (SColumnNode*)nodesMakeNode(QUERY_NODE_COLUMN);
+    if (NULL == pCol) {
+      return generateSyntaxErrMsg(&pCxt->msgBuf, TSDB_CODE_OUT_OF_MEMORY);
+    }
+    setColumnInfoBySchema(pTable, pTagsSchema + i, 1, pCol);
+    if (TSDB_CODE_SUCCESS != nodesListMakeStrictAppend(pOutput, (SNode*)pCol)) {
+      NODES_DESTORY_LIST(*pOutput);
+      return TSDB_CODE_OUT_OF_MEMORY;
+    }
+  }
+  return TSDB_CODE_SUCCESS;
+}
+
 static int32_t translateStar(STranslateContext* pCxt, SSelectStmt* pSelect) {
   SNode* pNode = NULL;
   WHERE_EACH(pNode, pSelect->pProjectionList) {
@@ -2598,10 +2659,14 @@ static int32_t translateStar(STranslateContext* pCxt, SSelectStmt* pSelect) {
         continue;
       }
     } else if (isMultiResFunc(pNode)) {
-      SNodeList* pFuncs = NULL;
-      code = createMultiResFuncsFromStar(pCxt, (SFunctionNode*)pNode, &pFuncs);
+      SNodeList* pNodeList = NULL;
+      if (FUNCTION_TYPE_TAGS == ((SFunctionNode*)pNode)->funcType) {
+        code = createTags(pCxt, &pNodeList);
+      } else {
+        code = createMultiResFuncsFromStar(pCxt, (SFunctionNode*)pNode, &pNodeList);
+      }
       if (TSDB_CODE_SUCCESS == code) {
-        INSERT_LIST(pSelect->pProjectionList, pFuncs);
+        INSERT_LIST(pSelect->pProjectionList, pNodeList);
         ERASE_NODE(pSelect->pProjectionList);
         continue;
       }
@@ -4579,6 +4644,8 @@ static SNode* createTbnameFunction() {
     return NULL;
   }
   strcpy(pFunc->functionName, "tbname");
+  strcpy(pFunc->node.aliasName, "tbname");
+  strcpy(pFunc->node.userAlias, "tbname");
   return (SNode*)pFunc;
 }
 
@@ -6007,7 +6074,7 @@ static SNode* createProjectCol(const char* pProjCol) {
 
 static SNodeList* createProjectCols(int32_t ncols, const char* const pCols[]) {
   SNodeList* pProjections = NULL;
-  if (ncols <= 0) {
+  if (0 == ncols) {
     nodesListMakeStrictAppend(&pProjections, createStarCol());
     return pProjections;
   }
@@ -6039,10 +6106,12 @@ static int32_t createSimpleSelectStmt(const char* pDb, const char* pTable, int32
   strcpy(pRealTable->table.tableAlias, pTable);
   pSelect->pFromTable = (SNode*)pRealTable;
 
-  pSelect->pProjectionList = createProjectCols(numOfProjs, pProjCol);
-  if (NULL == pSelect->pProjectionList) {
-    nodesDestroyNode((SNode*)pSelect);
-    return TSDB_CODE_OUT_OF_MEMORY;
+  if (numOfProjs >= 0) {
+    pSelect->pProjectionList = createProjectCols(numOfProjs, pProjCol);
+    if (NULL == pSelect->pProjectionList) {
+      nodesDestroyNode((SNode*)pSelect);
+      return TSDB_CODE_OUT_OF_MEMORY;
+    }
   }
 
   *pStmt = pSelect;
@@ -6145,6 +6214,40 @@ static int32_t rewriteShow(STranslateContext* pCxt, SQuery* pQuery) {
     pQuery->showRewrite = true;
     nodesDestroyNode(pQuery->pRoot);
     pQuery->pRoot = (SNode*)pStmt;
+  } else {
+    nodesDestroyNode((SNode*)pStmt);
+  }
+  return code;
+}
+
+static SNode* createTagsFunction() {
+  SFunctionNode* pFunc = (SFunctionNode*)nodesMakeNode(QUERY_NODE_FUNCTION);
+  if (NULL == pFunc) {
+    return NULL;
+  }
+  strcpy(pFunc->functionName, "_tags");
+  return (SNode*)pFunc;
+}
+
+static int32_t rewriteShowStableTags(STranslateContext* pCxt, SQuery* pQuery) {
+  const char*  cols[] = {"tbname", "_tags"};
+  SShowStmt*   pShow = (SShowStmt*)pQuery->pRoot;
+  SSelectStmt* pSelect = NULL;
+  int32_t code = createSimpleSelectStmt(((SValueNode*)pShow->pDbName)->literal, ((SValueNode*)pShow->pTbName)->literal,
+                                        -1, NULL, &pSelect);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = nodesListMakeStrictAppend(&pSelect->pProjectionList, createTbnameFunction());
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = nodesListMakeStrictAppend(&pSelect->pProjectionList, createTagsFunction());
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    pSelect->isDistinct = true;
+    pQuery->showRewrite = true;
+    nodesDestroyNode(pQuery->pRoot);
+    pQuery->pRoot = (SNode*)pSelect;
+  } else {
+    nodesDestroyNode((SNode*)pSelect);
   }
   return code;
 }
@@ -7282,6 +7385,9 @@ static int32_t rewriteQuery(STranslateContext* pCxt, SQuery* pQuery) {
     case QUERY_NODE_SHOW_TAGS_STMT:
       code = rewriteShow(pCxt, pQuery);
       break;
+    case QUERY_NODE_SHOW_TABLE_TAGS_STMT:
+      code = rewriteShowStableTags(pCxt, pQuery);
+      break;
     case QUERY_NODE_SHOW_DNODE_VARIABLES_STMT:
       code = rewriteShowDnodeVariables(pCxt, pQuery);
       break;

source/libs/planner/test/planBasicTest.cpp

@@ -180,6 +180,8 @@ TEST_F(PlanBasicTest, pseudoColumn) {
 
   run("SELECT _QSTART, _QEND, _QDURATION, _WSTART, _WEND, _WDURATION, COUNT(*) FROM t1 "
       "WHERE ts BETWEEN '2017-7-14 18:00:00' AND '2017-7-14 19:00:00' INTERVAL(10S)");
+
+  run("SELECT _TAGS, * FROM st1s1");
 }
 
 TEST_F(PlanBasicTest, indefiniteRowsFunc) {

source/libs/planner/test/planOtherTest.cpp

@@ -86,6 +86,8 @@ TEST_F(PlanOtherTest, show) {
   run("SHOW DNODE 1 VARIABLES");
 
   run("SHOW TAGS FROM st1s1");
+
+  run("SHOW TABLE TAGS FROM st1");
 }
 
 TEST_F(PlanOtherTest, delete) {

source/libs/sync/src/syncMain.c

@@ -2942,7 +2942,7 @@ static int32_t syncNodeConfigChangeFinish(SSyncNode* ths, SRpcMsg* pRpcMsg, SSyn
     cbMeta.newCfgTerm = pFinish->newCfgTerm;
     cbMeta.newCfgSeqNum = pFinish->newCfgSeqNum;
 
-    ths->pFsm->FpReConfigCb(ths->pFsm, pRpcMsg, cbMeta);
+    ths->pFsm->FpReConfigCb(ths->pFsm, pRpcMsg, &cbMeta);
   }
 
   // clear changing

source/libs/sync/test/syncConfigChangeSnapshotTest.cpp

@@ -149,9 +149,9 @@ int32_t SnapshotDoWrite(struct SSyncFSM* pFsm, void* pWriter, void* pBuf, int32_
 
 void RestoreFinishCb(struct SSyncFSM* pFsm) { sTrace("==callback== ==RestoreFinishCb=="); }
 
-void ReConfigCb(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta cbMeta) {
+void ReConfigCb(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta *cbMeta) {
   sTrace("==callback== ==ReConfigCb== flag:0x%lX, index:%" PRId64 ", code:%d, currentTerm:%" PRIu64 ", term:%" PRIu64,
-         cbMeta.flag, cbMeta.index, cbMeta.code, cbMeta.currentTerm, cbMeta.term);
+         cbMeta->flag, cbMeta->index, cbMeta->code, cbMeta->currentTerm, cbMeta->term);
 }
 
 SSyncFSM* createFsm() {

source/libs/sync/test/syncConfigChangeTest.cpp

@@ -80,9 +80,9 @@ int32_t GetSnapshotCb(struct SSyncFSM* pFsm, SSnapshot* pSnapshot) {
 
 void RestoreFinishCb(struct SSyncFSM* pFsm) { sTrace("==callback== ==RestoreFinishCb=="); }
 
-void ReConfigCb(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta cbMeta) {
+void ReConfigCb(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta *cbMeta) {
   sTrace("==callback== ==ReConfigCb== flag:0x%lX, index:%" PRId64 ", code:%d, currentTerm:%" PRIu64 ", term:%" PRIu64,
-         cbMeta.flag, cbMeta.index, cbMeta.code, cbMeta.currentTerm, cbMeta.term);
+         cbMeta->flag, cbMeta->index, cbMeta->code, cbMeta->currentTerm, cbMeta->term);
 }
 
 SSyncFSM* createFsm() {

source/libs/sync/test/syncTestTool.cpp

@@ -153,11 +153,11 @@ int32_t SnapshotDoWrite(struct SSyncFSM* pFsm, void* pWriter, void* pBuf, int32_
 
 void RestoreFinishCb(struct SSyncFSM* pFsm) { sTrace("==callback== ==RestoreFinishCb== pFsm:%p", pFsm); }
 
-void ReConfigCb(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta cbMeta) {
+void ReConfigCb(struct SSyncFSM* pFsm, const SRpcMsg* pMsg, SReConfigCbMeta* cbMeta) {
   char* s = syncCfg2Str(&(cbMeta.newCfg));
   sTrace("==callback== ==ReConfigCb== flag:0x%lX, index:%" PRId64 ", code:%d, currentTerm:%" PRIu64 ", term:%" PRIu64
          ", newCfg:%s",
-         cbMeta.flag, cbMeta.index, cbMeta.code, cbMeta.currentTerm, cbMeta.term, s);
+         cbMeta->flag, cbMeta->index, cbMeta->code, cbMeta->currentTerm, cbMeta->term, s);
   taosMemoryFree(s);
 }