diff --git a/include/libs/nodes/plannodes.h b/include/libs/nodes/plannodes.h
index 00380724b33b5e29b2c4d9b31d91872c849c8b98..b62854db43de4d90a2792b83bd444b9a02e3a15a 100644
--- a/include/libs/nodes/plannodes.h
+++ b/include/libs/nodes/plannodes.h
@@ -62,6 +62,7 @@ typedef struct SScanLogicNode {
   int64_t       watermark;
   int16_t       tsColId;
   double        filesFactor;
+  SArray*       pSmaIndexes;
 } SScanLogicNode;
 
 typedef struct SJoinLogicNode {
diff --git a/include/libs/nodes/querynodes.h b/include/libs/nodes/querynodes.h
index c2aa86e89f731cb6fdadb2911e805b55454fe2b4..33cc4a9c865241d39ca2b94317f93ffff4694581 100644
--- a/include/libs/nodes/querynodes.h
+++ b/include/libs/nodes/querynodes.h
@@ -144,6 +144,7 @@ typedef struct SRealTableNode {
   SVgroupsInfo*      pVgroupList;
   char               qualDbName[TSDB_DB_NAME_LEN];  // SHOW qualDbName.TABLES
   double             ratio;
+  SArray*            pSmaIndexes;
 } SRealTableNode;
 
 typedef struct STempTableNode {
diff --git a/include/util/tjson.h b/include/util/tjson.h
index 84f7b81726942098eb83a503e7fdbe7c092558e6..df433227ca83ce51e63a1265db9ac28ed0897954 100644
--- a/include/util/tjson.h
+++ b/include/util/tjson.h
@@ -17,16 +17,17 @@
 #define _TD_UTIL_JSON_H_
 
 #include "os.h"
+#include "tarray.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-#define tjsonGetNumberValue(pJson, pName, val, code)  \
-  do {                                                \
-    uint64_t _tmp = 0;                                \
+#define tjsonGetNumberValue(pJson, pName, val, code) \
+  do {                                               \
+    uint64_t _tmp = 0;                               \
     code = tjsonGetBigIntValue(pJson, pName, &_tmp); \
-    val = _tmp;                                       \
+    val = _tmp;                                      \
   } while (0)
 
 typedef void SJson;
@@ -66,18 +67,20 @@ typedef int32_t (*FToJson)(const void* pObj, SJson* pJson);
 int32_t tjsonAddObject(SJson* pJson, const char* pName, FToJson func, const void* pObj);
 int32_t tjsonAddItem(SJson* pJson, FToJson func, const void* pObj);
 int32_t tjsonAddArray(SJson* pJson, const char* pName, FToJson func, const void* pArray, int32_t itemSize, int32_t num);
+int32_t tjsonAddTArray(SJson* pJson, const char* pName, FToJson func, const SArray* pArray);
 
 typedef int32_t (*FToObject)(const SJson* pJson, void* pObj);
 
 int32_t tjsonToObject(const SJson* pJson, const char* pName, FToObject func, void* pObj);
 int32_t tjsonMakeObject(const SJson* pJson, const char* pName, FToObject func, void** pObj, int32_t objSize);
 int32_t tjsonToArray(const SJson* pJson, const char* pName, FToObject func, void* pArray, int32_t itemSize);
+int32_t tjsonToTArray(const SJson* pJson, const char* pName, FToObject func, SArray** pArray, int32_t itemSize);
 
 char* tjsonToString(const SJson* pJson);
 char* tjsonToUnformattedString(const SJson* pJson);
 
-SJson* tjsonParse(const char* pStr);
-bool   tjsonValidateJson(const char* pJson);
+SJson*      tjsonParse(const char* pStr);
+bool        tjsonValidateJson(const char* pJson);
 const char* tjsonGetError();
 
 #ifdef __cplusplus
diff --git a/source/libs/nodes/src/nodesCodeFuncs.c b/source/libs/nodes/src/nodesCodeFuncs.c
index 0735092c1a882567935a92230ecec76f61b11847..48840c4a8ba0d0443052c447e02153481a30fc1e 100644
--- a/source/libs/nodes/src/nodesCodeFuncs.c
+++ b/source/libs/nodes/src/nodesCodeFuncs.c
@@ -2809,10 +2809,85 @@ static int32_t jsonToTableNode(const SJson* pJson, void* pObj) {
   return code;
 }
 
+static const char* jkTableIndexInfoIntervalUnit = "IntervalUnit";
+static const char* jkTableIndexInfoSlidingUnit = "SlidingUnit";
+static const char* jkTableIndexInfoInterval = "Interval";
+static const char* jkTableIndexInfoOffset = "Offset";
+static const char* jkTableIndexInfoSliding = "Sliding";
+static const char* jkTableIndexInfoDstTbUid = "DstTbUid";
+static const char* jkTableIndexInfoDstVgId = "DstVgId";
+static const char* jkTableIndexInfoEpSet = "EpSet";
+static const char* jkTableIndexInfoExpr = "Expr";
+
+static int32_t tableIndexInfoToJson(const void* pObj, SJson* pJson) {
+  const STableIndexInfo* pNode = (const STableIndexInfo*)pObj;
+
+  int32_t code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoIntervalUnit, pNode->intervalUnit);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoSlidingUnit, pNode->slidingUnit);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoInterval, pNode->interval);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoOffset, pNode->offset);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoSliding, pNode->sliding);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoDstTbUid, pNode->dstTbUid);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddIntegerToObject(pJson, jkTableIndexInfoDstVgId, pNode->dstVgId);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddObject(pJson, jkTableIndexInfoEpSet, epSetToJson, &pNode->epSet);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddStringToObject(pJson, jkTableIndexInfoExpr, pNode->expr);
+  }
+
+  return code;
+}
+
+static int32_t jsonToTableIndexInfo(const SJson* pJson, void* pObj) {
+  STableIndexInfo* pNode = (STableIndexInfo*)pObj;
+
+  int32_t code = tjsonGetTinyIntValue(pJson, jkTableIndexInfoIntervalUnit, &pNode->intervalUnit);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetTinyIntValue(pJson, jkTableIndexInfoSlidingUnit, &pNode->slidingUnit);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetBigIntValue(pJson, jkTableIndexInfoInterval, &pNode->interval);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetBigIntValue(pJson, jkTableIndexInfoOffset, &pNode->offset);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetBigIntValue(pJson, jkTableIndexInfoSliding, &pNode->sliding);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetBigIntValue(pJson, jkTableIndexInfoDstTbUid, &pNode->dstTbUid);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonGetIntValue(pJson, jkTableIndexInfoDstVgId, &pNode->dstVgId);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonToObject(pJson, jkTableIndexInfoEpSet, jsonToEpSet, &pNode->epSet);
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonDupStringValue(pJson, jkTableIndexInfoExpr, &pNode->expr);
+  }
+
+  return code;
+}
+
 static const char* jkRealTableMetaSize = "MetaSize";
 static const char* jkRealTableMeta = "Meta";
 static const char* jkRealTableVgroupsInfoSize = "VgroupsInfoSize";
 static const char* jkRealTableVgroupsInfo = "VgroupsInfo";
+static const char* jkRealTableSmaIndexes = "SmaIndexes";
 
 static int32_t realTableNodeToJson(const void* pObj, SJson* pJson) {
   const SRealTableNode* pNode = (const SRealTableNode*)pObj;
@@ -2830,6 +2905,9 @@ static int32_t realTableNodeToJson(const void* pObj, SJson* pJson) {
   if (TSDB_CODE_SUCCESS == code) {
     code = tjsonAddObject(pJson, jkRealTableVgroupsInfo, vgroupsInfoToJson, pNode->pVgroupList);
   }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = tjsonAddTArray(pJson, jkRealTableSmaIndexes, tableIndexInfoToJson, pNode->pSmaIndexes);
+  }
 
   return code;
 }
@@ -2851,6 +2929,10 @@ static int32_t jsonToRealTableNode(const SJson* pJson, void* pObj) {
   if (TSDB_CODE_SUCCESS == code) {
     code = tjsonMakeObject(pJson, jkRealTableVgroupsInfo, jsonToVgroupsInfo, (void**)&pNode->pVgroupList, objSize);
   }
+  if (TSDB_CODE_SUCCESS == code) {
+    code =
+        tjsonToTArray(pJson, jkRealTableSmaIndexes, jsonToTableIndexInfo, &pNode->pSmaIndexes, sizeof(STableIndexInfo));
+  }
 
   return code;
 }
diff --git a/source/libs/parser/inc/parUtil.h b/source/libs/parser/inc/parUtil.h
index 42719d95bd47460de0a7406425496f37932a68e2..fb67a353686a843c825ea088489dcca4ee620b36 100644
--- a/source/libs/parser/inc/parUtil.h
+++ b/source/libs/parser/inc/parUtil.h
@@ -46,7 +46,7 @@ typedef struct SParseMetaCache {
   SHashObj* pDbInfo;       // key is tbFName, element is SDbInfo*
   SHashObj* pUserAuth;     // key is SUserAuthInfo serialized string, element is bool indicating whether or not to pass
   SHashObj* pUdf;          // key is funcName, element is SFuncInfo*
-  SHashObj* pSmaIndex;     // key is tbFName, element is SArray<STableIndexInfo>*
+  SHashObj* pTableIndex;   // key is tbFName, element is SArray<STableIndexInfo>*
 } SParseMetaCache;
 
 int32_t generateSyntaxErrMsg(SMsgBuf* pBuf, int32_t errCode, ...);
@@ -76,6 +76,7 @@ int32_t reserveUserAuthInCache(int32_t acctId, const char* pUser, const char* pD
                                SParseMetaCache* pMetaCache);
 int32_t reserveUserAuthInCacheExt(const char* pUser, const SName* pName, AUTH_TYPE type, SParseMetaCache* pMetaCache);
 int32_t reserveUdfInCache(const char* pFunc, SParseMetaCache* pMetaCache);
+int32_t reserveTableIndexInCache(int32_t acctId, const char* pDb, const char* pTable, SParseMetaCache* pMetaCache);
 int32_t getTableMetaFromCache(SParseMetaCache* pMetaCache, const SName* pName, STableMeta** pMeta);
 int32_t getDbVgInfoFromCache(SParseMetaCache* pMetaCache, const char* pDbFName, SArray** pVgInfo);
 int32_t getTableVgroupFromCache(SParseMetaCache* pMetaCache, const SName* pName, SVgroupInfo* pVgroup);
diff --git a/source/libs/parser/src/parAstParser.c b/source/libs/parser/src/parAstParser.c
index 6555ec3a7dd30a108f4dba53a4110be775e73eb2..6acc4575e7ab26055118033149fbfff5f3e0c660 100644
--- a/source/libs/parser/src/parAstParser.c
+++ b/source/libs/parser/src/parAstParser.c
@@ -129,6 +129,10 @@ static int32_t collectMetaKeyFromRealTableImpl(SCollectMetaKeyCxt* pCxt, SRealTa
   if (TSDB_CODE_SUCCESS == code) {
     code = reserveDbVgInfoInCache(pCxt->pParseCxt->acctId, pRealTable->table.dbName, pCxt->pMetaCache);
   }
+  if (TSDB_CODE_SUCCESS == code) {
+    code = reserveTableIndexInCache(pCxt->pParseCxt->acctId, pRealTable->table.dbName, pRealTable->table.tableName,
+                                    pCxt->pMetaCache);
+  }
   return code;
 }
 
diff --git a/source/libs/parser/src/parTranslater.c b/source/libs/parser/src/parTranslater.c
index 90da79266f43b1d07049011eb2c813ff4f390629..c2fa1ffd22ef559df69b834f0b1cfd3b612266a0 100644
--- a/source/libs/parser/src/parTranslater.c
+++ b/source/libs/parser/src/parTranslater.c
@@ -258,24 +258,19 @@ static int32_t getUdfInfo(STranslateContext* pCxt, SFunctionNode* pFunc) {
   return code;
 }
 
-static int32_t getTableIndex(STranslateContext* pCxt, const char* pDbName, const char* pTableName, SArray** pIndexes) {
+static int32_t getTableIndex(STranslateContext* pCxt, const SName* pName, SArray** pIndexes) {
   SParseContext* pParCxt = pCxt->pParseCxt;
-  SName          name;
-  toName(pParCxt->acctId, pDbName, pTableName, &name);
-  int32_t code = TSDB_CODE_SUCCESS;
+  int32_t        code = collectUseDatabase(pName, pCxt->pDbs);
+  if (TSDB_CODE_SUCCESS == code) {
+    code = collectUseTable(pName, pCxt->pTables);
+  }
   if (pParCxt->async) {
-    code = getTableIndexFromCache(pCxt->pMetaCache, &name, pIndexes);
+    code = getTableIndexFromCache(pCxt->pMetaCache, pName, pIndexes);
   } else {
-    code = collectUseDatabase(&name, pCxt->pDbs);
-    if (TSDB_CODE_SUCCESS == code) {
-      code = collectUseTable(&name, pCxt->pTables);
-    }
-    if (TSDB_CODE_SUCCESS == code) {
-      code = catalogGetTableIndex(pParCxt->pCatalog, pParCxt->pTransporter, &pParCxt->mgmtEpSet, &name, pIndexes);
-    }
+    code = catalogGetTableIndex(pParCxt->pCatalog, pParCxt->pTransporter, &pParCxt->mgmtEpSet, pName, pIndexes);
   }
   if (TSDB_CODE_SUCCESS != code) {
-    parserError("getTableIndex error, code:%s, dbName:%s, tbName:%s", tstrerror(code), pDbName, pTableName);
+    parserError("getTableIndex error, code:%s, dbName:%s, tbName:%s", tstrerror(code), pName->dbname, pName->tname);
   }
   return code;
 }
@@ -853,9 +848,9 @@ static EDealRes translateComparisonOperator(STranslateContext* pCxt, SOperatorNo
   }
   if (OP_TYPE_IN == pOp->opType || OP_TYPE_NOT_IN == pOp->opType) {
     SNodeListNode* pRight = (SNodeListNode*)pOp->pRight;
-    bool first = true;
-    SDataType targetDt = {0};
-    SNode* pNode = NULL;
+    bool           first = true;
+    SDataType      targetDt = {0};
+    SNode*         pNode = NULL;
     FOREACH(pNode, pRight->pNodeList) {
       SDataType dt = ((SExprNode*)pNode)->resType;
       if (first) {
@@ -1409,6 +1404,9 @@ static int32_t translateTable(STranslateContext* pCxt, SNode* pTable) {
           return generateSyntaxErrMsg(&pCxt->msgBuf, TSDB_CODE_PAR_TABLE_NOT_EXIST, pRealTable->table.tableName);
         }
         code = setTableVgroupList(pCxt, &name, pRealTable);
+        if (TSDB_CODE_SUCCESS == code) {
+          code = getTableIndex(pCxt, &name, &pRealTable->pSmaIndexes);
+        }
       }
       pRealTable->table.precision = pRealTable->pMeta->tableInfo.precision;
       pRealTable->table.singleTable = isSingleTable(pRealTable);
@@ -2018,33 +2016,8 @@ static int32_t rewriteTimelineFunc(STranslateContext* pCxt, SSelectStmt* pSelect
   nodesWalkSelectStmt(pSelect, SQL_CLAUSE_FROM, rewriteTimelineFuncImpl, pCxt);
   return pCxt->errCode;
 }
-#if 0
-static bool mayBeApplySmaIndex(SSelectStmt* pSelect) {
-  if (NULL == pSelect->pWindow || QUERY_NODE_INTERVAL_WINDOW != nodeType(pSelect->pWindow) ||
-      NULL != ((SIntervalWindowNode*)pSelect->pWindow)->pFill ||
-      QUERY_NODE_REAL_TABLE != nodeType(pSelect->pFromTable) || NULL != pSelect->pWhere ||
-      NULL != pSelect->pPartitionByList || NULL != pSelect->pGroupByList || NULL != pSelect->pHaving) {
-    return false;
-  }
-  return true;
-}
 
-static bool equalIntervalWindow(SIntervalWindowNode* pInterval, SNode* pWhere, STableIndexInfo* pIndex) {
-  int64_t interval = ((SValueNode*)pInterval->pInterval)->datum.i;
-  int8_t  intervalUnit = ((SValueNode*)pInterval->pInterval)->unit;
-  int64_t offset = (NULL != pInterval->pOffset ? ((SValueNode*)pInterval->pOffset)->datum.i : 0);
-  int64_t sliding = (NULL != pInterval->pSliding ? ((SValueNode*)pInterval->pSliding)->datum.i : interval);
-  int8_t  slidingUnit = (NULL != pInterval->pSliding ? ((SValueNode*)pInterval->pSliding)->unit : intervalUnit);
-  if (interval != pIndex->interval || intervalUnit != pIndex->intervalUnit || offset != pIndex->offset ||
-      sliding != pIndex->sliding || slidingUnit != pIndex->slidingUnit) {
-    return false;
-  }
-  // todo
-  if (NULL != pWhere) {
-    return false;
-  }
-  return true;
-}
+#if 0
 
 typedef struct SSmaIndexMatchFuncsCxt {
   int32_t    errCode;
@@ -2056,10 +2029,10 @@ typedef struct SSmaIndexMatchFuncsCxt {
   bool       match;
 } SSmaIndexMatchFuncsCxt;
 
-static SColumnNode* createColumnFromSmaFunc(uint64_t tableId, int32_t index, SExprNode* pSmaFunc) {
+static int32_t smaOptCreateSmaCol(SNode* pSmaFunc, int32_t index, SNode** pOutput) {
   SColumnNode* pCol = nodesMakeNode(QUERY_NODE_COLUMN);
   if (NULL == pCol) {
-    return NULL;
+    return TSDB_CODE_SUCCESS;
   }
   pCol->tableId = tableId;
   pCol->tableType = TSDB_SUPER_TABLE;
@@ -2070,7 +2043,7 @@ static SColumnNode* createColumnFromSmaFunc(uint64_t tableId, int32_t index, SEx
   strcpy(pCol->tableAlias, SMA_TABLE_NAME);
   pCol->node.resType = pSmaFunc->resType;
   strcpy(pCol->node.aliasName, pSmaFunc->aliasName);
-  return pCol;
+  return TSDB_CODE_SUCCESS;
 }
 
 static int32_t collectSmaFunc(SSmaIndexMatchFuncsCxt* pCxt, int32_t index, SNode* pSmaFunc) {
@@ -2262,25 +2235,6 @@ static int32_t attemptApplySmaIndexImpl(STranslateContext* pCxt, SSelectStmt* pS
   return TSDB_CODE_SUCCESS;
 }
 
-static void destroySmaIndex(void* p) { taosMemoryFree(((STableIndexInfo*)p)->expr); }
-
-static int32_t attemptApplySmaIndex(STranslateContext* pCxt, SSelectStmt* pSelect) {
-  SRealTableNode* pRealTable = (SRealTableNode*)pSelect->pFromTable;
-  SArray*         pIndexes = NULL;
-  int32_t         code = getTableIndex(pCxt, pRealTable->table.dbName, pRealTable->table.tableName, &pIndexes);
-  if (TSDB_CODE_SUCCESS == code) {
-    code = attemptApplySmaIndexImpl(pCxt, pSelect, pIndexes);
-  }
-  taosArrayDestroyEx(pIndexes, destroySmaIndex);
-  return code;
-}
-
-static int32_t attemptApplyIndex(STranslateContext* pCxt, SSelectStmt* pSelect) {
-  // if (mayBeApplySmaIndex(pSelect)) {
-  //   return attemptApplySmaIndex(pCxt, pSelect);
-  // }
-  return TSDB_CODE_SUCCESS;
-}
 #endif
 
 static int32_t translateSelect(STranslateContext* pCxt, SSelectStmt* pSelect) {
diff --git a/source/libs/parser/src/parUtil.c b/source/libs/parser/src/parUtil.c
index 41bb0481ada36b67eb4f6c9928c3c8f3905dc118..5bde056b5cc0607c904476f2f878b7b9e87b332c 100644
--- a/source/libs/parser/src/parUtil.c
+++ b/source/libs/parser/src/parUtil.c
@@ -807,6 +807,42 @@ int32_t getUdfInfoFromCache(SParseMetaCache* pMetaCache, const char* pFunc, SFun
   return code;
 }
 
+static void destroySmaIndex(void* p) { taosMemoryFree(((STableIndexInfo*)p)->expr); }
+
+static SArray* smaIndexesDup(SArray* pSrc) {
+  SArray* pDst = taosArrayDup(pSrc);
+  if (NULL == pDst) {
+    return NULL;
+  }
+  int32_t size = taosArrayGetSize(pDst);
+  for (int32_t i = 0; i < size; ++i) {
+    ((STableIndexInfo*)taosArrayGet(pDst, i))->expr = NULL;
+  }
+  for (int32_t i = 0; i < size; ++i) {
+    STableIndexInfo* pIndex = taosArrayGet(pDst, i);
+    pIndex->expr = taosMemoryStrDup(((STableIndexInfo*)taosArrayGet(pSrc, i))->expr);
+    if (NULL == pIndex->expr) {
+      taosArrayDestroyEx(pDst, destroySmaIndex);
+      return NULL;
+    }
+  }
+  return pDst;
+}
+
+int32_t reserveTableIndexInCache(int32_t acctId, const char* pDb, const char* pTable, SParseMetaCache* pMetaCache) {
+  return reserveTableReqInCache(acctId, pDb, pTable, &pMetaCache->pTableIndex);
+}
+
 int32_t getTableIndexFromCache(SParseMetaCache* pMetaCache, const SName* pName, SArray** pIndexes) {
-  return TSDB_CODE_PAR_INTERNAL_ERROR;
+  char fullName[TSDB_TABLE_FNAME_LEN];
+  tNameExtractFullName(pName, fullName);
+  SArray* pSmaIndexes = NULL;
+  int32_t code = getMetaDataFromHash(fullName, strlen(fullName), pMetaCache->pTableIndex, (void**)&pSmaIndexes);
+  if (TSDB_CODE_SUCCESS == code) {
+    *pIndexes = smaIndexesDup(pSmaIndexes);
+    if (NULL == *pIndexes) {
+      code = TSDB_CODE_OUT_OF_MEMORY;
+    }
+  }
+  return code;
 }
diff --git a/source/libs/parser/test/mockCatalog.cpp b/source/libs/parser/test/mockCatalog.cpp
index c7f09901328218473b87a6202793ef08dddba446..0b2aacf5ef11a99bd37d59c1c1ca1ce59c53c1b6 100644
--- a/source/libs/parser/test/mockCatalog.cpp
+++ b/source/libs/parser/test/mockCatalog.cpp
@@ -214,6 +214,11 @@ int32_t __catalogRefreshGetTableMeta(SCatalog* pCatalog, void* pTransporter, con
 
 int32_t __catalogRemoveTableMeta(SCatalog* pCtg, SName* pTableName) { return 0; }
 
+int32_t __catalogGetTableIndex(SCatalog* pCtg, void* pTrans, const SEpSet* pMgmtEps, const SName* pName,
+                               SArray** pRes) {
+  return g_mockCatalogService->catalogGetTableIndex(pName, pRes);
+}
+
 void initMetaDataEnv() {
   g_mockCatalogService.reset(new MockCatalogService());
 
@@ -230,6 +235,7 @@ void initMetaDataEnv() {
   stub.set(catalogGetUdfInfo, __catalogGetUdfInfo);
   stub.set(catalogRefreshGetTableMeta, __catalogRefreshGetTableMeta);
   stub.set(catalogRemoveTableMeta, __catalogRemoveTableMeta);
+  stub.set(catalogGetTableIndex, __catalogGetTableIndex);
   // {
   //   AddrAny any("libcatalog.so");
   //   std::map<std::string,void*> result;
diff --git a/source/libs/parser/test/mockCatalogService.cpp b/source/libs/parser/test/mockCatalogService.cpp
index 0c37c875c0bb7ae01df598b6c748a6b841c41891..c730653e5e796fd020fe2f98646ae79b7788b7cc 100644
--- a/source/libs/parser/test/mockCatalogService.cpp
+++ b/source/libs/parser/test/mockCatalogService.cpp
@@ -149,6 +149,20 @@ class MockCatalogServiceImpl {
     return TSDB_CODE_SUCCESS;
   }
 
+  int32_t catalogGetTableIndex(const SName* pTableName, SArray** pIndexes) const {
+    char tbFName[TSDB_TABLE_FNAME_LEN] = {0};
+    tNameExtractFullName(pTableName, tbFName);
+    auto it = index_.find(tbFName);
+    if (index_.end() == it) {
+      return TSDB_CODE_SUCCESS;
+    }
+    *pIndexes = taosArrayInit(it->second.size(), sizeof(STableIndexInfo));
+    for (const auto& index : it->second) {
+      taosArrayPush(*pIndexes, &index);
+    }
+    return TSDB_CODE_SUCCESS;
+  }
+
   int32_t catalogGetAllMeta(const SCatalogReq* pCatalogReq, SMetaData* pMetaData) const {
     int32_t code = getAllTableMeta(pCatalogReq->pTableMeta, &pMetaData->pTableMeta);
     if (TSDB_CODE_SUCCESS == code) {
@@ -176,7 +190,7 @@ class MockCatalogServiceImpl {
                                    int32_t numOfColumns, int32_t numOfTags) {
     builder_ = TableBuilder::createTableBuilder(tableType, numOfColumns, numOfTags);
     meta_[db][tbname] = builder_->table();
-    meta_[db][tbname]->schema->uid = id_++;
+    meta_[db][tbname]->schema->uid = getNextId();
     return *(builder_.get());
   }
 
@@ -187,14 +201,11 @@ class MockCatalogServiceImpl {
     }
     meta_[db][tbname].reset(new MockTableMeta());
     meta_[db][tbname]->schema = table.release();
-    meta_[db][tbname]->schema->uid = id_++;
+    meta_[db][tbname]->schema->uid = getNextId();
     meta_[db][tbname]->schema->tableType = TSDB_CHILD_TABLE;
 
     SVgroupInfo vgroup = {vgid, 0, 0, {0}, 0};
-    addEpIntoEpSet(&vgroup.epSet, "dnode_1", 6030);
-    addEpIntoEpSet(&vgroup.epSet, "dnode_2", 6030);
-    addEpIntoEpSet(&vgroup.epSet, "dnode_3", 6030);
-    vgroup.epSet.inUse = 0;
+    genEpSet(&vgroup.epSet);
 
     meta_[db][tbname]->vgs.emplace_back(vgroup);
     // super table
@@ -268,10 +279,39 @@ class MockCatalogServiceImpl {
     udf_.insert(std::make_pair(func, info));
   }
 
+  void createSmaIndex(const SMCreateSmaReq* pReq) {
+    STableIndexInfo info;
+    info.intervalUnit = pReq->intervalUnit;
+    info.slidingUnit = pReq->slidingUnit;
+    info.interval = pReq->interval;
+    info.offset = pReq->offset;
+    info.sliding = pReq->sliding;
+    info.dstTbUid = getNextId();
+    info.dstVgId = pReq->dstVgId;
+    genEpSet(&info.epSet);
+    info.expr = strdup(pReq->expr);
+    auto it = index_.find(pReq->stb);
+    if (index_.end() == it) {
+      index_.insert(std::make_pair(std::string(pReq->stb), std::vector<STableIndexInfo>{info}));
+    } else {
+      it->second.push_back(info);
+    }
+  }
+
  private:
   typedef std::map<std::string, std::shared_ptr<MockTableMeta>> TableMetaCache;
   typedef std::map<std::string, TableMetaCache>                 DbMetaCache;
   typedef std::map<std::string, std::shared_ptr<SFuncInfo>>     UdfMetaCache;
+  typedef std::map<std::string, std::vector<STableIndexInfo>>   IndexMetaCache;
+
+  uint64_t getNextId() { return id_++; }
+
+  void genEpSet(SEpSet* pEpSet) {
+    addEpIntoEpSet(pEpSet, "dnode_1", 6030);
+    addEpIntoEpSet(pEpSet, "dnode_2", 6030);
+    addEpIntoEpSet(pEpSet, "dnode_3", 6030);
+    pEpSet->inUse = 0;
+  }
 
   std::string toDbname(const std::string& dbFullName) const {
     std::string::size_type n = dbFullName.find(".");
@@ -467,6 +507,7 @@ class MockCatalogServiceImpl {
   std::unique_ptr<TableBuilder> builder_;
   DbMetaCache                   meta_;
   UdfMetaCache                  udf_;
+  IndexMetaCache                index_;
 };
 
 MockCatalogService::MockCatalogService() : impl_(new MockCatalogServiceImpl()) {}
@@ -490,6 +531,8 @@ void MockCatalogService::createFunction(const std::string& func, int8_t funcType
   impl_->createFunction(func, funcType, outputType, outputLen, bufSize);
 }
 
+void MockCatalogService::createSmaIndex(const SMCreateSmaReq* pReq) { impl_->createSmaIndex(pReq); }
+
 int32_t MockCatalogService::catalogGetTableMeta(const SName* pTableName, STableMeta** pTableMeta) const {
   return impl_->catalogGetTableMeta(pTableName, pTableMeta);
 }
@@ -510,6 +553,10 @@ int32_t MockCatalogService::catalogGetUdfInfo(const std::string& funcName, SFunc
   return impl_->catalogGetUdfInfo(funcName, pInfo);
 }
 
+int32_t MockCatalogService::catalogGetTableIndex(const SName* pTableName, SArray** pIndexes) const {
+  return impl_->catalogGetTableIndex(pTableName, pIndexes);
+}
+
 int32_t MockCatalogService::catalogGetAllMeta(const SCatalogReq* pCatalogReq, SMetaData* pMetaData) const {
   return impl_->catalogGetAllMeta(pCatalogReq, pMetaData);
 }
diff --git a/source/libs/parser/test/mockCatalogService.h b/source/libs/parser/test/mockCatalogService.h
index fafad81e95d8e2fe7056e44266107cd91100184e..c4ab091b7a76c3ed1562e9c2e91903471e340fef 100644
--- a/source/libs/parser/test/mockCatalogService.h
+++ b/source/libs/parser/test/mockCatalogService.h
@@ -64,6 +64,7 @@ class MockCatalogService {
   int32_t catalogGetTableDistVgInfo(const SName* pTableName, SArray** pVgList) const;
   int32_t catalogGetDBVgInfo(const char* pDbFName, SArray** pVgList) const;
   int32_t catalogGetUdfInfo(const std::string& funcName, SFuncInfo* pInfo) const;
+  int32_t catalogGetTableIndex(const SName* pTableName, SArray** pIndexes) const;
   int32_t catalogGetAllMeta(const SCatalogReq* pCatalogReq, SMetaData* pMetaData) const;
 
  private:
diff --git a/source/libs/planner/src/planOptimizer.c b/source/libs/planner/src/planOptimizer.c
index f252fe7265c9e9a5e875df284e747eb4ba7dbc5d..76338eb49117c4aadee3f3526e0d6322b99d1a8c 100644
--- a/source/libs/planner/src/planOptimizer.c
+++ b/source/libs/planner/src/planOptimizer.c
@@ -32,8 +32,7 @@ typedef struct SOptimizeContext {
   bool          optimized;
 } SOptimizeContext;
 
-typedef int32_t (*FMatch)(SOptimizeContext* pCxt, SLogicNode* pLogicNode);
-typedef int32_t (*FOptimize)(SOptimizeContext* pCxt, SLogicNode* pLogicNode);
+typedef int32_t (*FOptimize)(SOptimizeContext* pCxt, SLogicSubplan* pLogicSubplan);
 
 typedef struct SOptimizeRule {
   char*     pName;
@@ -109,7 +108,6 @@ static bool osdMayBeOptimized(SLogicNode* pNode) {
   }
   if (QUERY_NODE_LOGIC_PLAN_WINDOW == nodeType(pNode->pParent)) {
     return true;
-    // return (WINDOW_TYPE_INTERVAL == ((SWindowLogicNode*)pNode->pParent)->winType);
   }
   return !osdHaveNormalCol(((SAggLogicNode*)pNode->pParent)->pGroupKeys);
 }
@@ -231,9 +229,9 @@ static void setScanWindowInfo(SScanLogicNode* pScan) {
   }
 }
 
-static int32_t osdOptimize(SOptimizeContext* pCxt, SLogicNode* pLogicNode) {
+static int32_t osdOptimize(SOptimizeContext* pCxt, SLogicSubplan* pLogicSubplan) {
   SOsdInfo info = {0};
-  int32_t  code = osdMatch(pCxt, pLogicNode, &info);
+  int32_t  code = osdMatch(pCxt, pLogicSubplan->pNode, &info);
   if (TSDB_CODE_SUCCESS == code && info.pScan) {
     setScanWindowInfo((SScanLogicNode*)info.pScan);
   }
@@ -635,8 +633,8 @@ static int32_t cpdPushCondition(SOptimizeContext* pCxt, SLogicNode* pLogicNode)
   return code;
 }
 
-static int32_t cpdOptimize(SOptimizeContext* pCxt, SLogicNode* pLogicNode) {
-  return cpdPushCondition(pCxt, pLogicNode);
+static int32_t cpdOptimize(SOptimizeContext* pCxt, SLogicSubplan* pLogicSubplan) {
+  return cpdPushCondition(pCxt, pLogicSubplan->pNode);
 }
 
 static bool opkIsPrimaryKeyOrderBy(SNodeList* pSortKeys) {
@@ -745,26 +743,142 @@ static int32_t opkOptimizeImpl(SOptimizeContext* pCxt, SSortLogicNode* pSort) {
   return code;
 }
 
-static int32_t opkOptimize(SOptimizeContext* pCxt, SLogicNode* pLogicNode) {
-  SSortLogicNode* pSort = (SSortLogicNode*)optFindPossibleNode(pLogicNode, opkSortMayBeOptimized);
+static int32_t opkOptimize(SOptimizeContext* pCxt, SLogicSubplan* pLogicSubplan) {
+  SSortLogicNode* pSort = (SSortLogicNode*)optFindPossibleNode(pLogicSubplan->pNode, opkSortMayBeOptimized);
   if (NULL == pSort) {
     return TSDB_CODE_SUCCESS;
   }
   return opkOptimizeImpl(pCxt, pSort);
 }
 
-static const SOptimizeRule optimizeRuleSet[] = {{.pName = "OptimizeScanData", .optimizeFunc = osdOptimize},
-                                                {.pName = "ConditionPushDown", .optimizeFunc = cpdOptimize},
-                                                {.pName = "OrderByPrimaryKey", .optimizeFunc = opkOptimize}};
+static int32_t smaOptFindSmaFunc(SNodeList* pSmaFuncs, SNode* pFunc, SNode** pCol, bool* pFound) {
+  int32_t index = 0;
+  SNode*  pSmaFunc = NULL;
+  FOREACH(pSmaFunc, pSmaFuncs) {
+    if (nodesEqualNode(pSmaFunc, pFunc)) {
+      *pFound = true;
+      return collectSmaFunc(pCxt, index, pSmaFunc);
+    }
+    ++index;
+  }
+  return TSDB_CODE_SUCCESS;
+}
+
+static bool smaOptCouldApplyIndex(SScanLogicNode* pScan, STableIndexInfo* pIndex) {
+  if (pScan->interval != pIndex->interval || pScan->intervalUnit != pIndex->intervalUnit ||
+      pScan->offset != pIndex->offset || pScan->sliding != pIndex->sliding ||
+      pScan->slidingUnit != pIndex->slidingUnit) {
+    return false;
+  }
+  // todo time range
+  SNodeList* pFuncs = NULL;
+  SNode*     pFunc = NULL;
+  FOREACH(pFunc, ((SWindowLogicNode*)pScan->node.pParent)->pFuncs) {}
+
+  return true;
+}
+
+static bool smaOptMayBeOptimized(SLogicNode* pNode) {
+  if (QUERY_NODE_LOGIC_PLAN_SCAN != nodeType(pNode)) {
+    return false;
+  }
+
+  SScanLogicNode* pScan = (SScanLogicNode*)pNode;
+  if (0 == pScan->interval || NULL == pScan->pSmaIndexes || NULL != pScan->node.pConditions) {
+    return false;
+  }
+
+  int32_t size = taosArrayGetSize(pScan->pSmaIndexes);
+  for (int32_t i = 0; i < size; ++i) {
+    STableIndexInfo* pIndex = taosArrayGet(pScan->pSmaIndexes, i);
+  }
+
+  return false;
+}
+
+static int32_t smaOptCreateMerge(SNodeList* pTargets) {
+  SMergeLogicNode* pMerge = nodesMakeNode(QUERY_NODE_LOGIC_PLAN_MERGE);
+  if (NULL == pMerge) {
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  pMerge->node.precision = pPartChild->precision;
+  pMerge->pMergeKeys = pMergeKeys;
+
+  int32_t code = TSDB_CODE_SUCCESS;
+  pMerge->pInputs = nodesCloneList(pPartChild->pTargets);
+  pMerge->node.pTargets = nodesCloneList(pTargets);
+  if (NULL == pMerge->node.pTargets || NULL == pMerge->pInputs) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+  }
+  if (TSDB_CODE_SUCCESS == code) {
+    if (NULL == pSubplan) {
+      code = nodesListMakeAppend(&pSplitNode->pChildren, pMerge);
+    } else {
+      code = splReplaceLogicNode(pSubplan, pSplitNode, (SLogicNode*)pMerge);
+    }
+  }
+  if (TSDB_CODE_SUCCESS != code) {
+    nodesDestroyNode(pMerge);
+  }
+  return code;
+}
+
+static int32_t smaOptCreateSmaScan(SScanLogicNode* pScan, STableIndexInfo* pIndex, SNodeList* pCols,
+                                   SScanLogicNode** pOutput) {
+  SScanLogicNode* pSmaScan = nodesMakeNode(QUERY_NODE_LOGIC_PLAN_SCAN);
+  if (NULL == pSmaScan) {
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  pSmaScan->pScanCols = pCols;
+  pSmaScan->tableType = TSDB_SUPER_TABLE;
+  pSmaScan->tableId = pIndex->dstTbUid;
+  pSmaScan->stableId = pIndex->dstTbUid;
+  pSmaScan->scanType = SCAN_TYPE_TABLE;
+  pSmaScan->scanSeq[0] = pScan->scanSeq[0];
+  pSmaScan->scanSeq[1] = pScan->scanSeq[1];
+  pSmaScan->scanRange = pScan->scanRange;
+  pSmaScan->dataRequired = FUNC_DATA_REQUIRED_DATA_LOAD;
+
+  pSmaScan->pVgroupList = taosMemoryCalloc(1, sizeof(SVgroupsInfo) + sizeof(SVgroupInfo));
+  if (NULL == pSmaScan->pVgroupList) {
+    nodesDestroyNode(pSmaScan);
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  pSmaScan->pVgroupList->numOfVgroups = 1;
+  pSmaScan->pVgroupList->vgroups[0].vgId = pIndex->dstVgId;
+  memcpy(&(pSmaScan->pVgroupList->vgroups[0].epSet), &pIndex->epSet, sizeof(SEpSet));
+
+  *pOutput = pSmaScan;
+  return TSDB_CODE_SUCCESS;
+}
+
+static int32_t smaOptimizeImpl(SOptimizeContext* pCxt, SScanLogicNode* pScan) { return TSDB_CODE_SUCCESS; }
+
+static int32_t smaOptimize(SOptimizeContext* pCxt, SLogicNode* pLogicNode) {
+  SScanLogicNode* pScan = (SScanLogicNode*)optFindPossibleNode(pLogicNode, opkSortMayBeOptimized);
+  if (NULL == pScan) {
+    return TSDB_CODE_SUCCESS;
+  }
+  return smaOptimizeImpl(pCxt, pScan);
+}
+
+// clang-format off
+static const SOptimizeRule optimizeRuleSet[] = {
+  {.pName = "OptimizeScanData", .optimizeFunc = osdOptimize},
+  {.pName = "ConditionPushDown", .optimizeFunc = cpdOptimize},
+  {.pName = "OrderByPrimaryKey", .optimizeFunc = opkOptimize},
+  {.pName = "SmaIndex",          .optimizeFunc = smaOptimize}
+};
+// clang-format on
 
 static const int32_t optimizeRuleNum = (sizeof(optimizeRuleSet) / sizeof(SOptimizeRule));
 
-static int32_t applyOptimizeRule(SPlanContext* pCxt, SLogicNode* pLogicNode) {
+static int32_t applyOptimizeRule(SPlanContext* pCxt, SLogicSubplan* pLogicSubplan) {
   SOptimizeContext cxt = {.pPlanCxt = pCxt, .optimized = false};
   do {
     cxt.optimized = false;
     for (int32_t i = 0; i < optimizeRuleNum; ++i) {
-      int32_t code = optimizeRuleSet[i].optimizeFunc(&cxt, pLogicNode);
+      int32_t code = optimizeRuleSet[i].optimizeFunc(&cxt, pLogicSubplan);
       if (TSDB_CODE_SUCCESS != code) {
         return code;
       }
@@ -774,5 +888,5 @@ static int32_t applyOptimizeRule(SPlanContext* pCxt, SLogicNode* pLogicNode) {
 }
 
 int32_t optimizeLogicPlan(SPlanContext* pCxt, SLogicSubplan* pLogicSubplan) {
-  return applyOptimizeRule(pCxt, pLogicSubplan->pNode);
+  return applyOptimizeRule(pCxt, pLogicSubplan);
 }
diff --git a/source/libs/planner/test/planOtherTest.cpp b/source/libs/planner/test/planOtherTest.cpp
index 04d76a8b9132f18aa0cbd32375525153af172866..85f8b7d9f6a9308b6f15e38b2006ec29a26c4694 100644
--- a/source/libs/planner/test/planOtherTest.cpp
+++ b/source/libs/planner/test/planOtherTest.cpp
@@ -43,6 +43,8 @@ TEST_F(PlanOtherTest, createSmaIndex) {
   useDb("root", "test");
 
   run("CREATE SMA INDEX idx1 ON t1 FUNCTION(MAX(c1), MIN(c3 + 10), SUM(c4)) INTERVAL(10s)");
+
+  run("SELECT SUM(c4) FROM t1 INTERVAL(10s)");
 }
 
 TEST_F(PlanOtherTest, explain) {
diff --git a/source/libs/planner/test/planTestUtil.cpp b/source/libs/planner/test/planTestUtil.cpp
index 4e89f9d008a1a3667ed0b921243e39a1de09d54f..57d7cb66084836e13dd1f26b4ea90b67c0064d9a 100644
--- a/source/libs/planner/test/planTestUtil.cpp
+++ b/source/libs/planner/test/planTestUtil.cpp
@@ -14,12 +14,14 @@
  */
 
 #include "planTestUtil.h"
+
 #include <getopt.h>
 
 #include <algorithm>
 #include <array>
 
 #include "cmdnodes.h"
+#include "mockCatalogService.h"
 #include "parser.h"
 #include "planInt.h"
 
@@ -361,6 +363,7 @@ class PlannerTestBaseImpl {
     } else if (QUERY_NODE_CREATE_INDEX_STMT == nodeType(pQuery->pRoot)) {
       SMCreateSmaReq req = {0};
       tDeserializeSMCreateSmaReq(pQuery->pCmdMsg->pMsg, pQuery->pCmdMsg->msgLen, &req);
+      g_mockCatalogService->createSmaIndex(&req);
       nodesStringToNode(req.ast, &pCxt->pAstRoot);
       pCxt->streamQuery = true;
     } else if (QUERY_NODE_CREATE_STREAM_STMT == nodeType(pQuery->pRoot)) {
diff --git a/source/util/src/tjson.c b/source/util/src/tjson.c
index b15c188f04765bf7c7807a3bed43c58b47fac71a..45a2ffec779727e01113715396cd2cfc2942bc40 100644
--- a/source/util/src/tjson.c
+++ b/source/util/src/tjson.c
@@ -14,6 +14,7 @@
  */
 
 #define _DEFAULT_SOURCE
+
 #include "tjson.h"
 #include "cJSON.h"
 #include "taoserror.h"
@@ -138,6 +139,23 @@ int32_t tjsonAddArray(SJson* pJson, const char* pName, FToJson func, const void*
   return TSDB_CODE_SUCCESS;
 }
 
+int32_t tjsonAddTArray(SJson* pJson, const char* pName, FToJson func, const SArray* pArray) {
+  int32_t num = taosArrayGetSize(pArray);
+  if (num > 0) {
+    SJson* pJsonArray = tjsonAddArrayToObject(pJson, pName);
+    if (NULL == pJsonArray) {
+      return TSDB_CODE_OUT_OF_MEMORY;
+    }
+    for (int32_t i = 0; i < num; ++i) {
+      int32_t code = tjsonAddItem(pJsonArray, func, taosArrayGet(pArray, i));
+      if (TSDB_CODE_SUCCESS != code) {
+        return code;
+      }
+    }
+  }
+  return TSDB_CODE_SUCCESS;
+}
+
 char* tjsonToString(const SJson* pJson) { return cJSON_Print((cJSON*)pJson); }
 
 char* tjsonToUnformattedString(const SJson* pJson) { return cJSON_PrintUnformatted((cJSON*)pJson); }
@@ -184,7 +202,7 @@ int32_t tjsonGetBigIntValue(const SJson* pJson, const char* pName, int64_t* pVal
     return TSDB_CODE_FAILED;
   }
 #ifdef WINDOWS
-  sscanf(p,"%lld",pVal);
+  sscanf(p, "%lld", pVal);
 #else
   // sscanf(p,"%ld",pVal);
   *pVal = taosStr2Int64(p, NULL, 10);
@@ -219,7 +237,7 @@ int32_t tjsonGetUBigIntValue(const SJson* pJson, const char* pName, uint64_t* pV
     return TSDB_CODE_FAILED;
   }
 #ifdef WINDOWS
-  sscanf(p,"%llu",pVal);
+  sscanf(p, "%llu", pVal);
 #else
   // sscanf(p,"%ld",pVal);
   *pVal = taosStr2UInt64(p, NULL, 10);
@@ -299,24 +317,43 @@ int32_t tjsonToArray(const SJson* pJson, const char* pName, FToObject func, void
   return TSDB_CODE_SUCCESS;
 }
 
+int32_t tjsonToTArray(const SJson* pJson, const char* pName, FToObject func, SArray** pArray, int32_t itemSize) {
+  const cJSON* jArray = tjsonGetObjectItem(pJson, pName);
+  int32_t      size = tjsonGetArraySize(jArray);
+  if (size > 0) {
+    *pArray = taosArrayInit(size, itemSize);
+    if (NULL == *pArray) {
+      return TSDB_CODE_OUT_OF_MEMORY;
+    }
+    taosArraySetSize(*pArray, size);
+    for (int32_t i = 0; i < size; ++i) {
+      int32_t code = func(tjsonGetArrayItem(jArray, i), taosArrayGet(*pArray, i));
+      if (TSDB_CODE_SUCCESS != code) {
+        return code;
+      }
+    }
+  }
+  return TSDB_CODE_SUCCESS;
+}
+
 SJson* tjsonParse(const char* pStr) { return cJSON_Parse(pStr); }
 
-bool tjsonValidateJson(const char *jIn) {
-  if (!jIn){
+bool tjsonValidateJson(const char* jIn) {
+  if (!jIn) {
     return false;
   }
 
   // set json real data
-  cJSON *root = cJSON_Parse(jIn);
-  if (root == NULL){
+  cJSON* root = cJSON_Parse(jIn);
+  if (root == NULL) {
     return false;
   }
 
-  if(!cJSON_IsObject(root)){
+  if (!cJSON_IsObject(root)) {
     return false;
   }
   int size = cJSON_GetArraySize(root);
-  for(int i = 0; i < size; i++) {
+  for (int i = 0; i < size; i++) {
     cJSON* item = cJSON_GetArrayItem(root, i);
     if (!item) {
       return false;