Merge pull request #21985 from taosdata/fix/TS-3636

fix: desc table without permission to view any column issue

source/libs/command/src/command.c

@@ -87,7 +87,7 @@ static int32_t buildDescResultDataBlock(SSDataBlock** pOutput) {
   return code;
 }
 
-static void setDescResultIntoDataBlock(bool sysInfoUser, SSDataBlock* pBlock, int32_t numOfRows, STableMeta* pMeta) {
+static int32_t setDescResultIntoDataBlock(bool sysInfoUser, SSDataBlock* pBlock, int32_t numOfRows, STableMeta* pMeta) {
   blockDataEnsureCapacity(pBlock, numOfRows);
   pBlock->info.rows = 0;
 
@@ -114,6 +114,11 @@ static void setDescResultIntoDataBlock(bool sysInfoUser, SSDataBlock* pBlock, in
     colDataSetVal(pCol4, pBlock->info.rows, buf, false);
     ++(pBlock->info.rows);
   }
+  if (pBlock->info.rows <= 0) {
+    qError("no permission to view any columns");
+    return TSDB_CODE_PAR_PERMISSION_DENIED;
+  }
+  return TSDB_CODE_SUCCESS;
 }
 
 static int32_t execDescribe(bool sysInfoUser, SNode* pStmt, SRetrieveTableRsp** pRsp) {
@@ -123,7 +128,7 @@ static int32_t execDescribe(bool sysInfoUser, SNode* pStmt, SRetrieveTableRsp**
   SSDataBlock* pBlock = NULL;
   int32_t      code = buildDescResultDataBlock(&pBlock);
   if (TSDB_CODE_SUCCESS == code) {
-    setDescResultIntoDataBlock(sysInfoUser, pBlock, numOfRows, pDesc->pMeta);
+    code = setDescResultIntoDataBlock(sysInfoUser, pBlock, numOfRows, pDesc->pMeta);
   }
   if (TSDB_CODE_SUCCESS == code) {
     code = buildRetrieveTableRsp(pBlock, DESCRIBE_RESULT_COLS, pRsp);