enh: Code Optimization (#33283)

* enh: Code Optimization

* enh: redundant code

* fix: log error

Author: facetosea

source/client/src/clientSml.c

@@ -1118,6 +1118,7 @@ static int32_t smlModifyDBSchemas(SSmlHandle *info) {
     pName.tname[nameLen] = '\0';
     taosMemoryFree(measure);
 
+    pTableMeta = NULL;
     code = catalogGetSTableMeta(info->pCatalog, &conn, &pName, &pTableMeta);
 
     if (code == TSDB_CODE_PAR_TABLE_NOT_EXIST || code == TSDB_CODE_MND_STB_NOT_EXIST) {

source/libs/catalog/src/ctgCache.c

@@ -655,8 +655,11 @@ int32_t ctgReadTbMetaFromCache(SCatalog *pCtg, SCtgTbMetaCtx *ctx, STableMeta **
   int32_t      code = 0;
   SCtgDBCache *dbCache = NULL;
   SCtgTbCache *tbCache = NULL;
-  // taosMemoryFreeClear(*pTableMeta);
-  *pTableMeta = NULL;
+  if(*pTableMeta)  {
+    ctgError("Expected pTableMeta to be NULL, uid:0x%" PRIx64 ", suid:0x%" PRIx64, (*pTableMeta)->uid,
+             (*pTableMeta)->suid);
+    return TSDB_CODE_INVALID_PARA;
+  }
 
   char dbFName[TSDB_DB_FNAME_LEN] = {0};
   if (CTG_FLAG_IS_SYS_DB(ctx->flag)) {