enh: show table tags command extension

include/common/ttokendef.h

@@ -174,61 +174,61 @@
 #define TK_SUBSCRIPTIONS        156
 #define TK_VNODES               157
 #define TK_LIKE                 158
-#define TK_INDEX                159
-#define TK_FUNCTION             160
-#define TK_INTERVAL             161
-#define TK_TOPIC                162
-#define TK_AS                   163
-#define TK_WITH                 164
-#define TK_META                 165
-#define TK_CONSUMER             166
-#define TK_GROUP                167
-#define TK_DESC                 168
-#define TK_DESCRIBE             169
-#define TK_RESET                170
-#define TK_QUERY                171
-#define TK_CACHE                172
-#define TK_EXPLAIN              173
-#define TK_ANALYZE              174
-#define TK_VERBOSE              175
-#define TK_NK_BOOL              176
-#define TK_RATIO                177
-#define TK_NK_FLOAT             178
-#define TK_OUTPUTTYPE           179
-#define TK_AGGREGATE            180
-#define TK_BUFSIZE              181
-#define TK_STREAM               182
-#define TK_INTO                 183
-#define TK_TRIGGER              184
-#define TK_AT_ONCE              185
-#define TK_WINDOW_CLOSE         186
-#define TK_IGNORE               187
-#define TK_EXPIRED              188
-#define TK_FILL_HISTORY         189
-#define TK_SUBTABLE             190
-#define TK_KILL                 191
-#define TK_CONNECTION           192
-#define TK_TRANSACTION          193
-#define TK_BALANCE              194
-#define TK_VGROUP               195
-#define TK_MERGE                196
-#define TK_REDISTRIBUTE         197
-#define TK_SPLIT                198
-#define TK_DELETE               199
-#define TK_INSERT               200
-#define TK_NULL                 201
-#define TK_NK_QUESTION          202
-#define TK_NK_ARROW             203
-#define TK_ROWTS                204
-#define TK_TBNAME               205
-#define TK_QSTART               206
-#define TK_QEND                 207
-#define TK_QDURATION            208
-#define TK_WSTART               209
-#define TK_WEND                 210
-#define TK_WDURATION            211
-#define TK_IROWTS               212
-#define TK_QTAGS                213
+#define TK_TBNAME               159
+#define TK_QTAGS                160
+#define TK_AS                   161
+#define TK_INDEX                162
+#define TK_FUNCTION             163
+#define TK_INTERVAL             164
+#define TK_TOPIC                165
+#define TK_WITH                 166
+#define TK_META                 167
+#define TK_CONSUMER             168
+#define TK_GROUP                169
+#define TK_DESC                 170
+#define TK_DESCRIBE             171
+#define TK_RESET                172
+#define TK_QUERY                173
+#define TK_CACHE                174
+#define TK_EXPLAIN              175
+#define TK_ANALYZE              176
+#define TK_VERBOSE              177
+#define TK_NK_BOOL              178
+#define TK_RATIO                179
+#define TK_NK_FLOAT             180
+#define TK_OUTPUTTYPE           181
+#define TK_AGGREGATE            182
+#define TK_BUFSIZE              183
+#define TK_STREAM               184
+#define TK_INTO                 185
+#define TK_TRIGGER              186
+#define TK_AT_ONCE              187
+#define TK_WINDOW_CLOSE         188
+#define TK_IGNORE               189
+#define TK_EXPIRED              190
+#define TK_FILL_HISTORY         191
+#define TK_SUBTABLE             192
+#define TK_KILL                 193
+#define TK_CONNECTION           194
+#define TK_TRANSACTION          195
+#define TK_BALANCE              196
+#define TK_VGROUP               197
+#define TK_MERGE                198
+#define TK_REDISTRIBUTE         199
+#define TK_SPLIT                200
+#define TK_DELETE               201
+#define TK_INSERT               202
+#define TK_NULL                 203
+#define TK_NK_QUESTION          204
+#define TK_NK_ARROW             205
+#define TK_ROWTS                206
+#define TK_QSTART               207
+#define TK_QEND                 208
+#define TK_QDURATION            209
+#define TK_WSTART               210
+#define TK_WEND                 211
+#define TK_WDURATION            212
+#define TK_IROWTS               213
 #define TK_CAST                 214
 #define TK_NOW                  215
 #define TK_TODAY                216

include/libs/nodes/cmdnodes.h

@@ -284,6 +284,13 @@ typedef struct SShowVnodesStmt {
   SNode*    pDnodeEndpoint;
 } SShowVnodesStmt;
 
+typedef struct SShowTableTagsStmt {
+  ENodeType  type;
+  SNode*     pDbName;  // SValueNode
+  SNode*     pTbName;  // SValueNode
+  SNodeList* pTags;
+} SShowTableTagsStmt;
+
 typedef enum EIndexType { INDEX_TYPE_SMA = 1, INDEX_TYPE_FULLTEXT } EIndexType;
 
 typedef struct SIndexOptions {

include/libs/nodes/querynodes.h

@@ -297,6 +297,7 @@ typedef struct SSelectStmt {
   bool        hasStateKey;
   bool        onlyHasKeepOrderFunc;
   bool        groupSort;
+  bool        tagScan;
 } SSelectStmt;
 
 typedef enum ESetOperatorType { SET_OP_TYPE_UNION_ALL = 1, SET_OP_TYPE_UNION } ESetOperatorType;

source/libs/nodes/src/nodesUtilFuncs.c

@@ -424,8 +424,9 @@ 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_TABLE_TAGS_STMT:
+      return makeNode(type, sizeof(SShowTableTagsStmt));
     case QUERY_NODE_SHOW_DNODE_VARIABLES_STMT:
       return makeNode(type, sizeof(SShowDnodeVariablesStmt));
     case QUERY_NODE_SHOW_CREATE_DATABASE_STMT:
@@ -942,13 +943,19 @@ 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_TABLE_TAGS_STMT: {
+    case QUERY_NODE_SHOW_TAGS_STMT: {
       SShowStmt* pStmt = (SShowStmt*)pNode;
       nodesDestroyNode(pStmt->pDbName);
       nodesDestroyNode(pStmt->pTbName);
       break;
     }
+    case QUERY_NODE_SHOW_TABLE_TAGS_STMT: {
+      SShowTableTagsStmt* pStmt = (SShowTableTagsStmt*)pNode;
+      nodesDestroyNode(pStmt->pDbName);
+      nodesDestroyNode(pStmt->pTbName);
+      nodesDestroyList(pStmt->pTags);
+      break;
+    }
     case QUERY_NODE_SHOW_DNODE_VARIABLES_STMT:
       nodesDestroyNode(((SShowDnodeVariablesStmt*)pNode)->pDnodeId);
       nodesDestroyNode(((SShowDnodeVariablesStmt*)pNode)->pLikePattern);

source/libs/parser/inc/parAst.h

@@ -178,6 +178,7 @@ SNode* createShowCreateTableStmt(SAstCreateContext* pCxt, ENodeType type, SNode*
 SNode* createShowTableDistributedStmt(SAstCreateContext* pCxt, SNode* pRealTable);
 SNode* createShowDnodeVariablesStmt(SAstCreateContext* pCxt, SNode* pDnodeId, SNode* pLikePattern);
 SNode* createShowVnodesStmt(SAstCreateContext* pCxt, SNode* pDnodeId, SNode* pDnodeEndpoint);
+SNode* createShowTableTagsStmt(SAstCreateContext* pCxt, SNode* pTbName, SNode* pDbName, SNodeList* pTags);
 SNode* createCreateUserStmt(SAstCreateContext* pCxt, SToken* pUserName, const SToken* pPassword, int8_t sysinfo);
 SNode* createAlterUserStmt(SAstCreateContext* pCxt, SToken* pUserName, int8_t alterType, const SToken* pVal);
 SNode* createDropUserStmt(SAstCreateContext* pCxt, SToken* pUserName);

source/libs/parser/inc/sql.y

@@ -426,7 +426,7 @@ 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 TABLE TAGS tag_list_opt(C) FROM table_name_cond(A) from_db_opt(B).   { pCxt->pRootNode = createShowTableTagsStmt(pCxt, A, B, C); }
 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)); }
 
@@ -441,6 +441,18 @@ table_name_cond(A) ::= table_name(B).
 from_db_opt(A) ::= .                                                              { A = createDefaultDatabaseCondValue(pCxt); }
 from_db_opt(A) ::= FROM db_name(B).                                               { A = createIdentifierValueNode(pCxt, &B); }
 
+%type tag_list_opt                                                                { SNodeList* }
+%destructor tag_list_opt                                                          { nodesDestroyList($$); }
+tag_list_opt(A) ::= .                                                             { A = NULL; }
+tag_list_opt(A) ::= tag_item(B).                                                  { A = createNodeList(pCxt, B); }
+tag_list_opt(A) ::= tag_list_opt(B) NK_COMMA tag_item(C).                         { A = addNodeToList(pCxt, B, C); }
+
+tag_item(A) ::= TBNAME(B).                                                        { A = setProjectionAlias(pCxt, createFunctionNode(pCxt, &B, NULL), &B); }
+tag_item(A) ::= QTAGS(B).                                                         { A = createFunctionNode(pCxt, &B, NULL); }
+tag_item(A) ::= column_name(B).                                                   { A = createColumnNode(pCxt, NULL, &B); }
+tag_item(A) ::= column_name(B) column_alias(C).                                   { A = setProjectionAlias(pCxt, createColumnNode(pCxt, NULL, &B), &C); }
+tag_item(A) ::= column_name(B) AS column_alias(C).                                { A = setProjectionAlias(pCxt, createColumnNode(pCxt, NULL, &B), &C); }
+
 /************************************************ create index ********************************************************/
 cmd ::= CREATE SMA INDEX not_exists_opt(D) 
   full_table_name(A) ON full_table_name(B) index_options(C).                      { pCxt->pRootNode = createCreateIndexStmt(pCxt, INDEX_TYPE_SMA, D, A, B, NULL, C); }

source/libs/parser/src/parAstCreater.c

@@ -1390,6 +1390,21 @@ SNode* createShowVnodesStmt(SAstCreateContext* pCxt, SNode* pDnodeId, SNode* pDn
   return (SNode*)pStmt;
 }
 
+SNode* createShowTableTagsStmt(SAstCreateContext* pCxt, SNode* pTbName, SNode* pDbName, SNodeList* pTags) {
+  CHECK_PARSER_STATUS(pCxt);
+  if (NULL == pDbName) {
+    snprintf(pCxt->pQueryCxt->pMsg, pCxt->pQueryCxt->msgLen, "database not specified");
+    pCxt->errCode = TSDB_CODE_PAR_SYNTAX_ERROR;
+    return NULL;
+  }
+  SShowTableTagsStmt* pStmt = (SShowTableTagsStmt*)nodesMakeNode(QUERY_NODE_SHOW_TABLE_TAGS_STMT);
+  CHECK_OUT_OF_MEM(pStmt);
+  pStmt->pDbName = pDbName;
+  pStmt->pTbName = pTbName;
+  pStmt->pTags = pTags;
+  return (SNode*)pStmt;
+}
+
 SNode* createCreateUserStmt(SAstCreateContext* pCxt, SToken* pUserName, const SToken* pPassword, int8_t sysinfo) {
   CHECK_PARSER_STATUS(pCxt);
   char password[TSDB_USET_PASSWORD_LEN] = {0};

source/libs/parser/src/parAstParser.c

@@ -440,7 +440,7 @@ static int32_t collectMetaKeyFromShowTags(SCollectMetaKeyCxt* pCxt, SShowStmt* p
   return code;
 }
 
-static int32_t collectMetaKeyFromShowStableTags(SCollectMetaKeyCxt* pCxt, SShowStmt* pStmt) {
+static int32_t collectMetaKeyFromShowStableTags(SCollectMetaKeyCxt* pCxt, SShowTableTagsStmt* pStmt) {
   return collectMetaKeyFromRealTableImpl(pCxt, ((SValueNode*)pStmt->pDbName)->literal,
                                          ((SValueNode*)pStmt->pTbName)->literal, AUTH_TYPE_READ);
 }
@@ -627,7 +627,7 @@ static int32_t collectMetaKeyFromQuery(SCollectMetaKeyCxt* pCxt, SNode* pStmt) {
     case QUERY_NODE_SHOW_TAGS_STMT:
       return collectMetaKeyFromShowTags(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_TABLE_TAGS_STMT:
-      return collectMetaKeyFromShowStableTags(pCxt, (SShowStmt*)pStmt);
+      return collectMetaKeyFromShowStableTags(pCxt, (SShowTableTagsStmt*)pStmt);
     case QUERY_NODE_SHOW_USERS_STMT:
       return collectMetaKeyFromShowUsers(pCxt, (SShowStmt*)pStmt);
     case QUERY_NODE_SHOW_LICENCES_STMT:

source/libs/parser/src/parTranslater.c

@@ -4969,7 +4969,8 @@ static int32_t translateUseDatabase(STranslateContext* pCxt, SUseDatabaseStmt* p
   SName     name = {0};
   tNameSetDbName(&name, pCxt->pParseCxt->acctId, pStmt->dbName, strlen(pStmt->dbName));
   tNameExtractFullName(&name, usedbReq.db);
-  int32_t code = getDBVgVersion(pCxt, usedbReq.db, &usedbReq.vgVersion, &usedbReq.dbId, &usedbReq.numOfTable, &usedbReq.stateTs);
+  int32_t code =
+      getDBVgVersion(pCxt, usedbReq.db, &usedbReq.vgVersion, &usedbReq.dbId, &usedbReq.numOfTable, &usedbReq.stateTs);
   if (TSDB_CODE_SUCCESS == code) {
     code = buildCmdMsg(pCxt, TDMT_MND_USE_DB, (FSerializeFunc)tSerializeSUseDbReq, &usedbReq);
   }
@@ -6281,21 +6282,29 @@ static SNode* createTagsFunction() {
   return (SNode*)pFunc;
 }
 
+static int32_t createShowTableTagsProjections(SNodeList** pProjections, SNodeList** pTags) {
+  if (NULL != *pTags) {
+    TSWAP(*pProjections, *pTags);
+    return TSDB_CODE_SUCCESS;
+  }
+  int32_t code = nodesListMakeStrictAppend(pProjections, createTbnameFunction());
+  if (TSDB_CODE_SUCCESS == code) {
+    code = nodesListStrictAppend(*pProjections, createTagsFunction());
+  }
+  return code;
+}
+
 static int32_t rewriteShowStableTags(STranslateContext* pCxt, SQuery* pQuery) {
-  const char*  cols[] = {"tbname", "_tags"};
-  SShowStmt*   pShow = (SShowStmt*)pQuery->pRoot;
+  SShowTableTagsStmt* pShow = (SShowTableTagsStmt*)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());
+    code = createShowTableTagsProjections(&pSelect->pProjectionList, &pShow->pTags);
   }
   if (TSDB_CODE_SUCCESS == code) {
-    pSelect->isDistinct = true;
     pQuery->showRewrite = true;
+    pSelect->tagScan = true;
     nodesDestroyNode(pQuery->pRoot);
     pQuery->pRoot = (SNode*)pSelect;
   } else {

source/libs/parser/test/parShowToUse.cpp

@@ -192,6 +192,16 @@ TEST_F(ParserShowToUseTest, showTableDistributed) {
   run("SHOW TABLE DISTRIBUTED st1");
 }
 
+TEST_F(ParserShowToUseTest, showTableTags) {
+  useDb("root", "test");
+
+  run("SHOW TABLE TAGS FROM st1");
+
+  run("SHOW TABLE TAGS tag1, tag2 FROM st1");
+
+  run("SHOW TABLE TAGS TBNAME, _TAG, tag3 FROM st1");
+}
+
 TEST_F(ParserShowToUseTest, showTags) {
   useDb("root", "test");
 

source/libs/planner/src/planLogicCreater.c

@@ -189,7 +189,7 @@ static int32_t createSelectRootLogicNode(SLogicPlanContext* pCxt, SSelectStmt* p
 }
 
 static EScanType getScanType(SLogicPlanContext* pCxt, SNodeList* pScanPseudoCols, SNodeList* pScanCols,
-                             int8_t tableType) {
+                             int8_t tableType, bool tagScan) {
   if (pCxt->pPlanCxt->topicQuery || pCxt->pPlanCxt->streamQuery) {
     return SCAN_TYPE_STREAM;
   }
@@ -198,6 +198,10 @@ static EScanType getScanType(SLogicPlanContext* pCxt, SNodeList* pScanPseudoCols
     return SCAN_TYPE_SYSTEM_TABLE;
   }
 
+  if (tagScan) {
+    return SCAN_TYPE_TAG;
+  }
+
   if (NULL == pScanCols) {
     return NULL == pScanPseudoCols
                ? SCAN_TYPE_TABLE
@@ -310,7 +314,7 @@ static int32_t createScanLogicNode(SLogicPlanContext* pCxt, SSelectStmt* pSelect
     code = rewriteExprsForSelect(pScan->pScanPseudoCols, pSelect, SQL_CLAUSE_FROM);
   }
 
-  pScan->scanType = getScanType(pCxt, pScan->pScanPseudoCols, pScan->pScanCols, pScan->tableType);
+  pScan->scanType = getScanType(pCxt, pScan->pScanPseudoCols, pScan->pScanCols, pScan->tableType, pSelect->tagScan);
 
   if (NULL != pScan->pScanCols) {
     pScan->hasNormalCols = true;