[td-225] fix bugs in interp query

src/client/inc/tsclient.h

@@ -318,9 +318,10 @@ typedef struct SSqlObj {
   char             freed : 4;
   char             listed : 4;
   tsem_t           rspSem;
+  pthread_mutex_t  inUse; // make sure that one connection can only be utilized by one thread/process
   SSqlCmd          cmd;
   SSqlRes          res;
-  uint8_t          numOfSubs;
+  uint16_t         numOfSubs;
   struct SSqlObj **pSubs;
   struct SSqlObj * prev, *next;
 } SSqlObj;

src/client/src/tscServer.c

@@ -1846,17 +1846,6 @@ int tscProcessTableMetaRsp(SSqlObj *pSql) {
   size_t size = 0;
   STableMeta* pTableMeta = tscCreateTableMetaFromMsg(pMetaMsg, &size);
   
-#if 0
-  // if current table is created according to super table, get the table meta of super table
-  if (pTableMeta->tableType == TSDB_CHILD_TABLE) {
-    char id[TSDB_TABLE_ID_LEN + 1] = {0};
-    strncpy(id, pMetaMsg->stableId, TSDB_TABLE_ID_LEN);
-  
-    // NOTE: if the table meta of super table is not cached at client side yet, the pSTable is NULL
-    pTableMeta->pSTable = taosCacheAcquireByName(tscCacheHandle, id);
-  }
-#endif
-  
   // todo add one more function: taosAddDataIfNotExists();
   STableMetaInfo *pTableMetaInfo = tscGetTableMetaInfoFromCmd(&pSql->cmd, 0, 0);
   assert(pTableMetaInfo->pTableMeta == NULL);
@@ -1978,7 +1967,7 @@ int tscProcessMultiMeterMetaRsp(SSqlObj *pSql) {
   
   pSql->res.code = TSDB_CODE_SUCCESS;
   pSql->res.numOfTotal = i;
-  tscTrace("%p load multi-metermeta resp complete num:%d", pSql, pSql->res.numOfTotal);
+  tscTrace("%p load multi-metermeta resp from complete num:%d", pSql, pSql->res.numOfTotal);
 #endif
   
   return TSDB_CODE_SUCCESS;

src/client/src/tscSql.c

@@ -123,6 +123,13 @@ STscObj *taosConnectImpl(const char *ip, const char *user, const char *pass, con
   
   tsem_init(&pSql->rspSem, 0, 0);
   
+  pthread_mutexattr_t mutexattr;
+  memset(&mutexattr, 0, sizeof(pthread_mutexattr_t));
+  
+  pthread_mutexattr_settype(&mutexattr, PTHREAD_MUTEX_RECURSIVE_NP);
+  pthread_mutex_init(&pSql->inUse, &mutexattr);
+  pthread_mutexattr_destroy(&mutexattr);
+
   pObj->pSql = pSql;
   pObj->pDnodeConn = pDnodeConn;
   
@@ -284,12 +291,23 @@ int taos_query(TAOS *taos, const char *sqlstr) {
   }
   
   SSqlObj* pSql = pObj->pSql;
+  SSqlCmd* pCmd = &pSql->cmd;
+  
+  // now this TAOS_CONN object is in use by one thread
+  pthread_mutex_lock(&pSql->inUse);
   
   size_t sqlLen = strlen(sqlstr);
   doAsyncQuery(pObj, pSql, waitForQueryRsp, taos, sqlstr, sqlLen);
 
   // wait for the callback function to post the semaphore
-  sem_wait(&pSql->rspSem);
+  tsem_wait(&pSql->rspSem);
+  
+  if (pCmd->command != TSDB_SQL_SELECT &&
+      pCmd->command != TSDB_SQL_SHOW &&
+      pCmd->command != TSDB_SQL_DESCRIBE_TABLE) {
+    pthread_mutex_unlock(&pSql->inUse);
+  }
+  
   return pSql->res.code;
 }
 
@@ -525,7 +543,7 @@ int taos_select_db(TAOS *taos, const char *db) {
   return taos_query(taos, sql);
 }
 
-void taos_free_result_imp(TAOS_RES *res, int keepCmd) {
+void taos_free_result(TAOS_RES *res) {
   if (res == NULL) return;
 
   SSqlObj *pSql = (SSqlObj *)res;
@@ -536,26 +554,24 @@ void taos_free_result_imp(TAOS_RES *res, int keepCmd) {
 
   if (pSql->signature != pSql) return;
 
+  STscObj* pObj = pSql->pTscObj;
   if (pRes == NULL || pRes->qhandle == 0) {
     /* Query rsp is not received from vnode, so the qhandle is NULL */
     tscTrace("%p qhandle is null, abort free, fp:%p", pSql, pSql->fp);
-    STscObj* pTscObj = pSql->pTscObj;
     
-    if (pTscObj->pSql != pSql) {
+    // The semaphore can not be changed while freeing async sub query objects.
+    if (pObj->pSql != pSql) {
       tscTrace("%p SqlObj is freed by app", pSql);
       tscFreeSqlObj(pSql);
-    } else {
-      if (keepCmd) {
-        tscFreeSqlResult(pSql);
     } else {
       tscPartiallyFreeSqlObj(pSql);
-      }
+      pthread_mutex_unlock(&pSql->inUse); // now this TAOS_CONN can be used by other threads
     }
   
     return;
   }
 
-  // set freeFlag to 1 in retrieve message if there are un-retrieved results
+  // set freeFlag to 1 in retrieve message if there are un-retrieved results data in node
   SQueryInfo *pQueryInfo = tscGetQueryInfoDetail(&pSql->cmd, 0);
   if (pQueryInfo == NULL) {
     tscPartiallyFreeSqlObj(pSql);
@@ -599,20 +615,13 @@ void taos_free_result_imp(TAOS_RES *res, int keepCmd) {
     if (pTscObj->pSql != pSql) {
       tscFreeSqlObj(pSql);
       tscTrace("%p sql result is freed by app", pSql);
-    } else {
-      if (keepCmd) {
-        tscFreeSqlResult(pSql);
-        tscTrace("%p sql result is freed while sql command is kept", pSql);
     } else {
       tscPartiallyFreeSqlObj(pSql);
       tscTrace("%p sql result is freed by app", pSql);
     }
   }
-  }
 }
 
-void taos_free_result(TAOS_RES *res) { taos_free_result_imp(res, 0); }
-
 // todo should not be used in async query
 int taos_errno(TAOS *taos) {
   STscObj *pObj = (STscObj *)taos;

src/client/src/tscUtil.c

@@ -1767,11 +1767,12 @@ SSqlObj* createSubqueryObj(SSqlObj* pSql, int16_t tableIndex, void (*fp)(), void
   pNewQueryInfo->limit  = pQueryInfo->limit;
   pNewQueryInfo->slimit = pQueryInfo->slimit;
   pNewQueryInfo->order  = pQueryInfo->order;
-  pNewQueryInfo->clauseLimit = pQueryInfo->clauseLimit;
-  pNewQueryInfo->pTableMetaInfo = NULL;
+  pNewQueryInfo->tsBuf  = NULL;
+  pNewQueryInfo->fillType = pQueryInfo->fillType;
   pNewQueryInfo->fillVal  = NULL;
+  pNewQueryInfo->clauseLimit = pQueryInfo->clauseLimit;
   pNewQueryInfo->numOfTables = 0;
-  pNewQueryInfo->tsBuf = NULL;
+  pNewQueryInfo->pTableMetaInfo = NULL;
   
   pNewQueryInfo->groupbyExpr = pQueryInfo->groupbyExpr;
   if (pQueryInfo->groupbyExpr.columnInfo != NULL) {

src/query/src/qExecutor.c

@@ -4525,14 +4525,13 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
 
   size_t numOfGroups = taosArrayGetSize(pQInfo->groupInfo.pGroupList);
 
-  if (isPointInterpoQuery(pQuery)) {
+  if (isPointInterpoQuery(pQuery) || isFirstLastRowQuery(pQuery)) {
     resetCtxOutputBuf(pRuntimeEnv);
     assert(pQuery->limit.offset == 0 && pQuery->limit.limit != 0);
 
     while (pQInfo->groupIndex < numOfGroups) {
       SArray* group = taosArrayGetP(pQInfo->groupInfo.pGroupList, pQInfo->groupIndex);
 
-      if (isFirstLastRowQuery(pQuery)) {
       qTrace("QInfo:%p last_row query on group:%d, total group:%d, current group:%d", pQInfo, pQInfo->groupIndex,
              numOfGroups);
 
@@ -4555,7 +4554,11 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
         pRuntimeEnv->pQueryHandle = NULL;
       }
       
+      if (isFirstLastRowQuery(pQuery)) {
         pRuntimeEnv->pQueryHandle = tsdbQueryLastRow(pQInfo->tsdb, &cond, &gp);
+      } else {
+        pRuntimeEnv->pQueryHandle = tsdbQueryRowsInExternalWindow(pQInfo->tsdb, &cond, &gp);
+      }
       
       initCtxOutputBuf(pRuntimeEnv);
       setTagVal(pRuntimeEnv, (STableId*) taosArrayGet(tx, 0), pQInfo->tsdb);
@@ -4576,7 +4579,6 @@ static void sequentialTableProcess(SQInfo *pQInfo) {
       // enable execution for next table, when handling the projection query
       enableExecutionForNextTable(pRuntimeEnv);
     }
-    }
   } else {
     /*
      * 1. super table projection query, 2. group-by on normal columns query, 3. ts-comp query