feat: show create table, desc table with col comments

include/libs/nodes/cmdnodes.h

@@ -23,10 +23,11 @@ extern "C" {
 #include "query.h"
 #include "querynodes.h"
 
-#define DESCRIBE_RESULT_COLS      4
-#define DESCRIBE_RESULT_FIELD_LEN (TSDB_COL_NAME_LEN - 1 + VARSTR_HEADER_SIZE)
-#define DESCRIBE_RESULT_TYPE_LEN  (20 + VARSTR_HEADER_SIZE)
-#define DESCRIBE_RESULT_NOTE_LEN  (8 + VARSTR_HEADER_SIZE)
+#define DESCRIBE_RESULT_COLS            5
+#define DESCRIBE_RESULT_FIELD_LEN       (TSDB_COL_NAME_LEN - 1 + VARSTR_HEADER_SIZE)
+#define DESCRIBE_RESULT_TYPE_LEN        (20 + VARSTR_HEADER_SIZE)
+#define DESCRIBE_RESULT_NOTE_LEN        (8 + VARSTR_HEADER_SIZE)
+#define DESCRIBE_RESULT_COL_COMMENT_LEN (TSDB_COL_COMMENT_LEN)
 
 #define SHOW_CREATE_DB_RESULT_COLS       2
 #define SHOW_CREATE_DB_RESULT_FIELD1_LEN (TSDB_DB_NAME_LEN + VARSTR_HEADER_SIZE)

source/common/src/tmsg.c

@@ -2305,7 +2305,7 @@ int32_t tDeserializeSTableCfgRsp(void *buf, int32_t bufLen, STableCfgRsp *pRsp)
   }
 
   int32_t totalCols = pRsp->numOfTags + pRsp->numOfColumns;
-  pRsp->pSchemas = taosMemoryMalloc(sizeof(SSchema) * totalCols);
+  pRsp->pSchemas = taosMemoryCalloc(totalCols, sizeof(SSchema));
   if (pRsp->pSchemas == NULL) return -1;
 
   for (int32_t i = 0; i < totalCols; ++i) {
@@ -3688,7 +3688,7 @@ static int32_t tDecodeSTableMetaRsp(SDecoder *pDecoder, STableMetaRsp *pRsp) {
 
   int32_t totalCols = pRsp->numOfTags + pRsp->numOfColumns;
   if (totalCols > 0) {
-    pRsp->pSchemas = taosMemoryMalloc(sizeof(SSchema) * totalCols);
+    pRsp->pSchemas = taosMemoryCalloc(totalCols, sizeof(SSchema));
     if (pRsp->pSchemas == NULL) return -1;
 
     for (int32_t i = 0; i < totalCols; ++i) {

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

@@ -216,7 +216,7 @@ int vnodeGetTableCfg(SVnode *pVnode, SRpcMsg *pMsg, bool direct) {
 
   cfgRsp.numOfTags = schemaTag.nCols;
   cfgRsp.numOfColumns = schema.nCols;
-  cfgRsp.pSchemas = (SSchema *)taosMemoryMalloc(sizeof(SSchema) * (cfgRsp.numOfColumns + cfgRsp.numOfTags));
+  cfgRsp.pSchemas = (SSchema *)taosMemoryCalloc(cfgRsp.numOfColumns + cfgRsp.numOfTags, sizeof(SSchema));
 
   memcpy(cfgRsp.pSchemas, schema.pSchema, sizeof(SSchema) * schema.nCols);
   if (schemaTag.nCols) {

source/libs/command/src/command.c

@@ -78,6 +78,10 @@ static int32_t buildDescResultDataBlock(SSDataBlock** pOutput) {
     infoData = createColumnInfoData(TSDB_DATA_TYPE_VARCHAR, DESCRIBE_RESULT_NOTE_LEN, 4);
     code = blockDataAppendColInfo(pBlock, &infoData);
   }
+  if (TSDB_CODE_SUCCESS == code) {
+    infoData = createColumnInfoData(TSDB_DATA_TYPE_VARCHAR, DESCRIBE_RESULT_COL_COMMENT_LEN, 5);
+    code = blockDataAppendColInfo(pBlock, &infoData);
+  }
 
   if (TSDB_CODE_SUCCESS == code) {
     *pOutput = pBlock;
@@ -99,7 +103,9 @@ static int32_t setDescResultIntoDataBlock(bool sysInfoUser, SSDataBlock* pBlock,
   SColumnInfoData* pCol3 = taosArrayGet(pBlock->pDataBlock, 2);
   // Note
   SColumnInfoData* pCol4 = taosArrayGet(pBlock->pDataBlock, 3);
-  char             buf[DESCRIBE_RESULT_FIELD_LEN] = {0};
+  // Comment
+  SColumnInfoData* pCol5 = taosArrayGet(pBlock->pDataBlock, 4);
+  char             buf[DESCRIBE_RESULT_COL_COMMENT_LEN + VARSTR_HEADER_SIZE] = {0};
   for (int32_t i = 0; i < numOfRows; ++i) {
     if (invisibleColumn(sysInfoUser, pMeta->tableType, pMeta->schema[i].flags)) {
       continue;
@@ -112,6 +118,8 @@ static int32_t setDescResultIntoDataBlock(bool sysInfoUser, SSDataBlock* pBlock,
     colDataSetVal(pCol3, pBlock->info.rows, (const char*)&bytes, false);
     STR_TO_VARSTR(buf, i >= pMeta->tableInfo.numOfColumns ? "TAG" : "");
     colDataSetVal(pCol4, pBlock->info.rows, buf, false);
+    STR_TO_VARSTR(buf, pMeta->schema[i].comment);
+    colDataSetVal(pCol5, pBlock->info.rows, buf, false);
     ++(pBlock->info.rows);
   }
   if (pBlock->info.rows <= 0) {
@@ -456,14 +464,19 @@ void appendColumnFields(char* buf, int32_t* len, STableCfg* pCfg) {
   for (int32_t i = 0; i < pCfg->numOfColumns; ++i) {
     SSchema* pSchema = pCfg->pSchemas + i;
     char     type[32];
+    char     comments[TSDB_COL_COMMENT_LEN + 16] = {0};
     sprintf(type, "%s", tDataTypes[pSchema->type].name);
     if (TSDB_DATA_TYPE_VARCHAR == pSchema->type || TSDB_DATA_TYPE_GEOMETRY == pSchema->type) {
       sprintf(type + strlen(type), "(%d)", (int32_t)(pSchema->bytes - VARSTR_HEADER_SIZE));
     } else if (TSDB_DATA_TYPE_NCHAR == pSchema->type) {
       sprintf(type + strlen(type), "(%d)", (int32_t)((pSchema->bytes - VARSTR_HEADER_SIZE) / TSDB_NCHAR_SIZE));
     }
+    if (pSchema->comment[0]) {
+      sprintf(comments, " COMMENT '%s'", pSchema->comment);
+    }
 
-    *len += sprintf(buf + VARSTR_HEADER_SIZE + *len, "%s`%s` %s", ((i > 0) ? ", " : ""), pSchema->name, type);
+    *len +=
+        sprintf(buf + VARSTR_HEADER_SIZE + *len, "%s`%s` %s%s", ((i > 0) ? ", " : ""), pSchema->name, type, comments);
   }
 }
 
@@ -471,14 +484,18 @@ void appendTagFields(char* buf, int32_t* len, STableCfg* pCfg) {
   for (int32_t i = 0; i < pCfg->numOfTags; ++i) {
     SSchema* pSchema = pCfg->pSchemas + pCfg->numOfColumns + i;
     char     type[32];
+    char     comments[TSDB_COL_COMMENT_LEN + 16] = {0};
     sprintf(type, "%s", tDataTypes[pSchema->type].name);
     if (TSDB_DATA_TYPE_VARCHAR == pSchema->type || TSDB_DATA_TYPE_GEOMETRY == pSchema->type) {
       sprintf(type + strlen(type), "(%d)", (int32_t)(pSchema->bytes - VARSTR_HEADER_SIZE));
     } else if (TSDB_DATA_TYPE_NCHAR == pSchema->type) {
       sprintf(type + strlen(type), "(%d)", (int32_t)((pSchema->bytes - VARSTR_HEADER_SIZE) / TSDB_NCHAR_SIZE));
     }
+    if (pSchema->comment[0]) {
+      sprintf(comments, " COMMENT '%s'", pSchema->comment);
+    }
 
-    *len += sprintf(buf + VARSTR_HEADER_SIZE + *len, "%s`%s` %s", ((i > 0) ? ", " : ""), pSchema->name, type);
+    *len += sprintf(buf + VARSTR_HEADER_SIZE + *len, "%s`%s` %s%s", ((i > 0) ? ", " : ""), pSchema->name, type, comments);
   }
 }
 

source/libs/parser/src/parTranslater.c

@@ -7683,6 +7683,10 @@ static int32_t extractDescribeResultSchema(int32_t* numOfCols, SSchema** pSchema
   (*pSchema)[3].bytes = DESCRIBE_RESULT_NOTE_LEN;
   strcpy((*pSchema)[3].name, "note");
 
+  (*pSchema)[4].type = TSDB_DATA_TYPE_BINARY;
+  (*pSchema)[4].bytes = DESCRIBE_RESULT_COL_COMMENT_LEN;
+  strcpy((*pSchema)[4].name, "comment");
+
   return TSDB_CODE_SUCCESS;
 }
 

tests/system-test/0-others/show.py

@@ -222,6 +222,15 @@ class TDTestCase:
         tdSql.query('show create table super_table')
         create_sql = "create stable `super_table` (`ts` timestamp, `c2` int) tags (`tg` int)"
         tdSql.checkEqual(tdSql.queryResult[0][1].lower(), create_sql)
+
+        tdSql.query("desc normal_table")
+        tdSql.checkCols(5)
+        tdSql.checkData(0, 4, "")
+
+        tdSql.query("desc super_table")
+        tdSql.checkCols(5)
+        tdSql.checkData(0, 4, "")
+
         tdSql.execute("drop database comment_test_db")
 
     def alter_table_with_col_comment(self):