[td-2859]refactor.

src/client/src/tscSQLParser.c

@@ -6374,12 +6374,12 @@ int32_t doCheckForStream(SSqlObj* pSql, SSqlInfo* pInfo) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg1);
   }
   
-  SArray* pSrcMeterName = pInfo->pCreateTableInfo->pSelect->from;
-  if (pSrcMeterName == NULL || taosArrayGetSize(pSrcMeterName) == 0) {
+  SFromInfo* pFromInfo = pInfo->pCreateTableInfo->pSelect->from;
+  if (pFromInfo == NULL || taosArrayGetSize(pFromInfo->tableList) == 0) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg6);
   }
   
-  tVariantListItem* p1 = taosArrayGet(pSrcMeterName, 0);
+  tVariantListItem* p1 = taosArrayGet(pFromInfo->tableList, 0);
   SStrToken srcToken = {.z = p1->pVar.pz, .n = p1->pVar.nLen, .type = TK_STRING};
   if (tscValidateName(&srcToken) != TSDB_CODE_SUCCESS) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg1);
@@ -6498,7 +6498,7 @@ static int32_t checkQueryRangeForFill(SSqlCmd* pCmd, SQueryInfo* pQueryInfo) {
 }
 
 int32_t doValidateSqlNode(SSqlObj* pSql, SQuerySqlNode* pQuerySqlNode, int32_t index) {
-  assert(pQuerySqlNode != NULL && (pQuerySqlNode->from == NULL || taosArrayGetSize(pQuerySqlNode->from) > 0));
+  assert(pQuerySqlNode != NULL && (pQuerySqlNode->from == NULL || taosArrayGetSize(pQuerySqlNode->from->tableList) > 0));
 
   const char* msg0 = "invalid table name";
   const char* msg1 = "point interpolation query needs timestamp";
@@ -6539,60 +6539,59 @@ int32_t doValidateSqlNode(SSqlObj* pSql, SQuerySqlNode* pQuerySqlNode, int32_t i
     return doLocalQueryProcess(pCmd, pQueryInfo, pQuerySqlNode);
   }
 
-  size_t fromSize = taosArrayGetSize(pQuerySqlNode->from);
-  if (fromSize > TSDB_MAX_JOIN_TABLE_NUM * 2) {
+  size_t fromSize = taosArrayGetSize(pQuerySqlNode->from->tableList);
+  if (fromSize > TSDB_MAX_JOIN_TABLE_NUM) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg4);
   }
 
   pQueryInfo->command = TSDB_SQL_SELECT;
 
-  if (fromSize > 4) {
+  if (fromSize > 2) {
     return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg6);
   }
 
   // set all query tables, which are maybe more than one.
   for (int32_t i = 0; i < fromSize; ) {
-    tVariantListItem* item = taosArrayGet(pQuerySqlNode->from, i);
-    tVariant* pTableItem = &item->pVar;
+    STableNamePair* item = taosArrayGet(pQuerySqlNode->from->tableList, i);
+    SStrToken* pTableItem = &item->name;
 
-    if (pTableItem->nType != TSDB_DATA_TYPE_BINARY) {
+    if (pTableItem->type != TSDB_DATA_TYPE_BINARY) {
       return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg0);
     }
 
-    pTableItem->nLen = strdequote(pTableItem->pz);
+    pTableItem->n = strdequote(pTableItem->z);
 
-    SStrToken tableName = {.z = pTableItem->pz, .n = pTableItem->nLen, .type = TK_STRING};
+    SStrToken tableName = {.z = pTableItem->z, .n = pTableItem->n, .type = TK_STRING};
     if (tscValidateName(&tableName) != TSDB_CODE_SUCCESS) {
       return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg0);
     }
 
-    if (pQueryInfo->numOfTables <= i/2) {  // more than one table
+    if (pQueryInfo->numOfTables <= i) {  // more than one table
       tscAddEmptyMetaInfo(pQueryInfo);
     }
 
     STableMetaInfo* pTableMetaInfo1 = tscGetMetaInfo(pQueryInfo, i/2);
 
-    SStrToken t = {.type = TSDB_DATA_TYPE_BINARY, .n = pTableItem->nLen, .z = pTableItem->pz};
+    SStrToken t = {.type = TSDB_DATA_TYPE_BINARY, .n = pTableItem->n, .z = pTableItem->z};
     code = tscSetTableFullName(pTableMetaInfo1, &t, pSql);
     if (code != TSDB_CODE_SUCCESS) {
       return code;
     }
 
-    tVariantListItem* p1 = taosArrayGet(pQuerySqlNode->from, i + 1);
-    if (p1->pVar.nType != TSDB_DATA_TYPE_BINARY) {
+    SStrToken* aliasName = &item->aliasName;
+    if (aliasName->type != TSDB_DATA_TYPE_BINARY) {
       return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg7);
     }
 
-    SStrToken aliasName = {.z = p1->pVar.pz, .n = p1->pVar.nLen, .type = TK_STRING};
-    if (tscValidateName(&aliasName) != TSDB_CODE_SUCCESS) {
+    if (TPARSER_HAS_TOKEN(*aliasName) && tscValidateName(aliasName) != TSDB_CODE_SUCCESS) {
       return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg7);
     }
 
     // has no table alias name
-    if (memcmp(pTableItem->pz, p1->pVar.pz, p1->pVar.nLen) == 0) {
-      strncpy(pTableMetaInfo1->aliasName, tNameGetTableName(&pTableMetaInfo1->name), tListLen(pTableMetaInfo->aliasName));
+    if (!TPARSER_HAS_TOKEN(*aliasName)) {
+      strncpy(pTableMetaInfo1->aliasName, tNameGetTableName(&pTableMetaInfo1->name), tListLen(pTableMetaInfo1->aliasName));
     } else {
-      tstrncpy(pTableMetaInfo1->aliasName, p1->pVar.pz, sizeof(pTableMetaInfo1->aliasName));
+      tstrncpy(pTableMetaInfo1->aliasName, aliasName->z, sizeof(pTableMetaInfo1->aliasName));
     }
 
     code = tscGetTableMeta(pSql, pTableMetaInfo1);
@@ -6603,7 +6602,7 @@ int32_t doValidateSqlNode(SSqlObj* pSql, SQuerySqlNode* pQuerySqlNode, int32_t i
     i += 2;
   }
 
-  assert(pQueryInfo->numOfTables == taosArrayGetSize(pQuerySqlNode->from) / 2);
+  assert(pQueryInfo->numOfTables == taosArrayGetSize(pQuerySqlNode->from->tableList) / 2);
   bool isSTable = false;
   
   if (UTIL_TABLE_IS_SUPER_TABLE(pTableMetaInfo)) {
@@ -6637,12 +6636,12 @@ int32_t doValidateSqlNode(SSqlObj* pSql, SQuerySqlNode* pQuerySqlNode, int32_t i
       pQueryInfo->window.ekey = pQueryInfo->window.ekey / 1000;
     }
   } else {  // set the time rang
-    if (taosArrayGetSize(pQuerySqlNode->from) > 2) { // it is a join query, no wher clause is not allowed.
+    if (taosArrayGetSize(pQuerySqlNode->from->tableList) > 1) { // it is a join query, no where clause is not allowed.
       return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), "condition missing for join query ");
     }
   }
 
-  int32_t joinQuery = (pQuerySqlNode->from != NULL && taosArrayGetSize(pQuerySqlNode->from) > 2);
+  int32_t joinQuery = (pQuerySqlNode->from != NULL && taosArrayGetSize(pQuerySqlNode->from->tableList) > 1);
   int32_t timeWindowQuery =
       (TPARSER_HAS_TOKEN(pQuerySqlNode->interval.interval) || TPARSER_HAS_TOKEN(pQuerySqlNode->sessionVal.gap));
 

src/client/src/tscUtil.c

@@ -1159,7 +1159,7 @@ SSqlExpr* tscSqlExprInsert(SQueryInfo* pQueryInfo, int32_t index, int16_t functi
 }
 
 SSqlExpr* tscSqlExprAppend(SQueryInfo* pQueryInfo, int16_t functionId, SColumnIndex* pColIndex, int16_t type,
-    int16_t size, int16_t resColId, int16_t interSize, bool isTagCol) {
+                           int16_t size, int16_t resColId, int16_t interSize, bool isTagCol) {
   SSqlExpr* pExpr = doCreateSqlExpr(pQueryInfo, functionId, pColIndex, type, size, resColId, interSize, isTagCol);
   taosArrayPush(pQueryInfo->exprList, &pExpr);
   return pExpr;

src/query/inc/qSqlparser.h

@@ -39,6 +39,11 @@ enum SQL_NODE_TYPE {
   SQL_NODE_EXPR        = 4,
 };
 
+enum SQL_NODE_FROM_TYPE {
+  SQL_NODE_FROM_SUBQUERY  = 1,
+  SQL_NODE_FROM_NAMELIST  = 2,
+};
+
 extern char tTokenTypeSwitcher[13];
 
 #define toTSDBType(x)                          \
@@ -78,12 +83,14 @@ typedef struct SSessionWindowVal {
   SStrToken          gap;
 } SSessionWindowVal;
 
+struct SFromInfo;
+
 typedef struct SQuerySqlNode {
   struct SArray     *pSelectList;  // select clause
-  SArray            *from;         // from clause  SArray<SQuerySqlNode>
+  struct SFromInfo  *from;         // from clause SArray<SQuerySqlNode>
   struct tSqlExpr   *pWhere;       // where clause [optional]
   SArray            *pGroupby;     // groupby clause, only for tags[optional], SArray<tVariantListItem>
-  SArray            *pSortOrder;   // orderby [optional], SArray<tVariantListItem>
+  SArray            *pSortOrder;   // orderby [optional],  SArray<tVariantListItem>
   SArray            *fillType;     // fill type[optional], SArray<tVariantListItem>
   SIntervalVal       interval;     // (interval, interval_offset) [optional]
   SSessionWindowVal  sessionVal;   // session window [optional]
@@ -93,6 +100,24 @@ typedef struct SQuerySqlNode {
   SStrToken          sqlstr;       // sql string in select clause
 } SQuerySqlNode;
 
+typedef struct STableNamePair {
+  SStrToken name;
+  SStrToken aliasName;
+} STableNamePair;
+
+typedef struct SSubclauseInfo {  // "UNION" multiple select sub-clause
+  SQuerySqlNode    **pClause;
+  int32_t            numOfClause;
+} SSubclauseInfo;
+
+typedef struct SFromInfo {
+  int32_t            type;        // nested query|table name list
+  union {
+    SSubclauseInfo  *pNode;
+    SArray          *tableList;   // SArray<STableNamePair>
+  };
+} SFromInfo;
+
 typedef struct SCreatedTableInfo {
   SStrToken          name;        // table name token
   SStrToken          stableName;  // super table name token , for using clause
@@ -188,11 +213,6 @@ typedef struct SMiscInfo {
   };
 } SMiscInfo;
 
-typedef struct SSubclauseInfo {  // "UNION" multiple select sub-clause
-  SQuerySqlNode    **pClause;
-  int32_t            numOfClause;
-} SSubclauseInfo;
-
 typedef struct SSqlInfo {
   int32_t            type;
   bool               valid;
@@ -233,6 +253,10 @@ SArray *tVariantListAppend(SArray *pList, tVariant *pVar, uint8_t sortOrder);
 SArray *tVariantListInsert(SArray *pList, tVariant *pVar, uint8_t sortOrder, int32_t index);
 SArray *tVariantListAppendToken(SArray *pList, SStrToken *pAliasToken, uint8_t sortOrder);
 
+SFromInfo *setTableNameList(SFromInfo* pFromInfo, SStrToken *pName, SStrToken* pAlias);
+SFromInfo *setSubquery(SFromInfo* pFromInfo, SQuerySqlNode *pSqlNode);
+void      *destroyFromInfo(SFromInfo* pFromInfo);
+
 // sql expr leaf node
 tSqlExpr *tSqlExprCreateIdValue(SStrToken *pToken, int32_t optrType);
 tSqlExpr *tSqlExprCreateFunction(SArray *pParam, SStrToken *pFuncToken, SStrToken *endToken, int32_t optType);
@@ -246,7 +270,7 @@ void      tSqlExprDestroy(tSqlExpr *pExpr);
 SArray   *tSqlExprListAppend(SArray *pList, tSqlExpr *pNode, SStrToken *pDistinct, SStrToken *pToken);
 void      tSqlExprListDestroy(SArray *pList);
 
-SQuerySqlNode *tSetQuerySqlNode(SStrToken *pSelectToken, SArray *pSelectList, SArray *pFrom, tSqlExpr *pWhere,
+SQuerySqlNode *tSetQuerySqlNode(SStrToken *pSelectToken, SArray *pSelectList, SFromInfo *pFrom, tSqlExpr *pWhere,
                                 SArray *pGroupby, SArray *pSortOrder, SIntervalVal *pInterval, SSessionWindowVal *ps,
                                 SStrToken *pSliding, SArray *pFill, SLimitVal *pLimit, SLimitVal *pgLimit);
 

src/query/src/qSqlParser.c

@@ -443,6 +443,49 @@ SArray *tVariantListInsert(SArray *pList, tVariant *pVar, uint8_t sortOrder, int
   return pList;
 }
 
+SFromInfo *setTableNameList(SFromInfo* pFromInfo, SStrToken *pName, SStrToken* pAlias) {
+  if (pFromInfo == NULL) {
+    pFromInfo = calloc(1, sizeof(SFromInfo));
+    pFromInfo->tableList = taosArrayInit(4, sizeof(STableNamePair));
+  }
+
+  pFromInfo->type = SQL_NODE_FROM_NAMELIST;
+  STableNamePair p = {.name = *pName};
+  if (pAlias != NULL) {
+    p.aliasName = *pAlias;
+  } else {
+    TPARSER_SET_NONE_TOKEN(p.aliasName);
+  }
+
+  taosArrayPush(pFromInfo->tableList, &p);
+
+  return pFromInfo;
+}
+
+SFromInfo *setSubquery(SFromInfo* pFromInfo, SQuerySqlNode* pSqlNode) {
+  if (pFromInfo == NULL) {
+    pFromInfo = calloc(1, sizeof(SFromInfo));
+  }
+
+  pFromInfo->type = SQL_NODE_FROM_SUBQUERY;
+  pFromInfo->pNode->pClause[pFromInfo->pNode->numOfClause - 1] = pSqlNode;
+
+  return pFromInfo;
+}
+
+void* destroyFromInfo(SFromInfo* pFromInfo) {
+  assert(pFromInfo != NULL);
+  if (pFromInfo->type == SQL_NODE_FROM_NAMELIST) {
+    taosArrayDestroy(pFromInfo->tableList);
+  } else {
+    destroyAllSelectClause(pFromInfo->pNode);
+  }
+
+  tfree(pFromInfo);
+  return NULL;
+}
+
+
 void tSetDbName(SStrToken *pCpxName, SStrToken *pDb) {
   pCpxName->type = pDb->type;
   pCpxName->z = pDb->z;
@@ -582,9 +625,10 @@ void tSetColumnType(TAOS_FIELD *pField, SStrToken *type) {
 /*
  * extract the select info out of sql string
  */
-SQuerySqlNode *tSetQuerySqlNode(SStrToken *pSelectToken, SArray *pSelectList, SArray *pFrom, tSqlExpr *pWhere,
-                             SArray *pGroupby, SArray *pSortOrder, SIntervalVal *pInterval, SSessionWindowVal *pSession,
-                             SStrToken *pSliding, SArray *pFill, SLimitVal *pLimit, SLimitVal *psLimit) {
+SQuerySqlNode *tSetQuerySqlNode(SStrToken *pSelectToken, SArray *pSelectList, SFromInfo *pFrom, tSqlExpr *pWhere,
+                                SArray *pGroupby, SArray *pSortOrder, SIntervalVal *pInterval,
+                                SSessionWindowVal *pSession, SStrToken *pSliding, SArray *pFill, SLimitVal *pLimit,
+                                SLimitVal *psLimit) {
   assert(pSelectList != NULL);
 
   SQuerySqlNode *pSqlNode = calloc(1, sizeof(SQuerySqlNode));
@@ -668,8 +712,7 @@ void destroyQuerySqlNode(SQuerySqlNode *pQuerySql) {
   taosArrayDestroyEx(pQuerySql->pGroupby, freeVariant);
   pQuerySql->pGroupby = NULL;
 
-  taosArrayDestroyEx(pQuerySql->from, freeVariant);
-  pQuerySql->from = NULL;
+  pQuerySql->from = destroyFromInfo(pQuerySql->from);
 
   taosArrayDestroyEx(pQuerySql->fillType, freeVariant);
   pQuerySql->fillType = NULL;