Merge remote-tracking branch 'origin/develop' into feature/wal

cmake/install.inc

@@ -13,6 +13,7 @@ ELSEIF (TD_WINDOWS)
   INSTALL(DIRECTORY ${TD_COMMUNITY_DIR}/src/connector/go     DESTINATION connector)
   INSTALL(DIRECTORY ${TD_COMMUNITY_DIR}/src/connector/nodejs DESTINATION connector)
   INSTALL(DIRECTORY ${TD_COMMUNITY_DIR}/src/connector/python DESTINATION connector)
+  INSTALL(DIRECTORY ${TD_COMMUNITY_DIR}/src/connector/C\# DESTINATION connector)
   INSTALL(DIRECTORY ${TD_COMMUNITY_DIR}/tests/examples DESTINATION .)
   INSTALL(DIRECTORY ${TD_COMMUNITY_DIR}/packaging/cfg DESTINATION .)
   INSTALL(FILES ${TD_COMMUNITY_DIR}/src/inc/taos.h DESTINATION include)

documentation20/webdocs/markdowndocs/architecture-ch.md

@@ -221,7 +221,7 @@ TDengine采用时间驱动缓存管理策略（First-In-First-Out，FIFO），
 
 TDengine通过查询函数向用户提供毫秒级的数据获取能力。直接将最近到达的数据保存在缓存中，可以更加快速地响应用户针对最近一条或一批数据的查询分析，整体上提供更快的数据库查询响应能力。从这个意义上来说，**可通过设置合适的配置参数将TDengine作为数据缓存来使用，而不需要再部署Redis或其他额外的缓存系统**，可有效地简化系统架构，降低运维的成本。需要注意的是，TDengine重启以后系统的缓存将被清空，之前缓存的数据均会被批量写入磁盘，缓存的数据将不会像专门的Key-value缓存系统再将之前缓存的数据重新加载到缓存中。
 
-每个vnode有自己独立的内存，而且由多个固定大小的内存块组成，不同vnode之间完全隔离。数据写入时，类似于日志的写法，数据被顺序追加写入内存，但每个vnode维护有自己的skip list，便于迅速查找。当一半以上的内存块写满时，启动落盘操作，而且后续写的操作在新的内存块进行。这样，一个vnode里有一半内存块是保留有最近的数据的，以达到缓存、快速查找的目的。一个vnode的内存块的个数由配置参数blocks决定，内存块的大小由配置参数cache决定。
+每个vnode有自己独立的内存，而且由多个固定大小的内存块组成，不同vnode之间完全隔离。数据写入时，类似于日志的写法，数据被顺序追加写入内存，但每个vnode维护有自己的skip list，便于迅速查找。当三分之一以上的内存块写满时，启动落盘操作，而且后续写的操作在新的内存块进行。这样，一个vnode里有三分之一内存块是保留有最近的数据的，以达到缓存、快速查找的目的。一个vnode的内存块的个数由配置参数blocks决定，内存块的大小由配置参数cache决定。
 
 ### 持久化存储
 TDengine采用数据驱动的方式让缓存中的数据写入硬盘进行持久化存储。当vnode中缓存的数据达到一定规模时，为了不阻塞后续数据的写入，TDengine也会拉起落盘线程将缓存的数据写入持久化存储。TDengine在数据落盘时会打开新的数据库日志文件，在落盘成功后则会删除老的数据库日志文件，避免日志文件无限制的增长。

src/connector/C#/TDengineDriver.cs

+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+
+namespace TDengineDriver
+{
+  enum TDengineDataType {
+    TSDB_DATA_TYPE_NULL = 0,     // 1 bytes
+    TSDB_DATA_TYPE_BOOL = 1,     // 1 bytes
+    TSDB_DATA_TYPE_TINYINT = 2,  // 1 bytes
+    TSDB_DATA_TYPE_SMALLINT = 3, // 2 bytes
+    TSDB_DATA_TYPE_INT = 4,      // 4 bytes
+    TSDB_DATA_TYPE_BIGINT = 5,   // 8 bytes
+    TSDB_DATA_TYPE_FLOAT = 6,    // 4 bytes
+    TSDB_DATA_TYPE_DOUBLE = 7,   // 8 bytes
+    TSDB_DATA_TYPE_BINARY = 8,   // string
+    TSDB_DATA_TYPE_TIMESTAMP = 9,// 8 bytes
+    TSDB_DATA_TYPE_NCHAR = 10    // unicode string
+  }
+
+  enum TDengineInitOption
+  {
+    TSDB_OPTION_LOCALE = 0,
+    TSDB_OPTION_CHARSET = 1,
+    TSDB_OPTION_TIMEZONE = 2,
+    TDDB_OPTION_CONFIGDIR = 3,
+    TDDB_OPTION_SHELL_ACTIVITY_TIMER = 4
+  }
+
+  class TDengineMeta
+  {
+    public string name;
+    public short size;
+    public byte type;
+    public string TypeName()
+    {
+      switch ((TDengineDataType)type)
+      {
+        case TDengineDataType.TSDB_DATA_TYPE_BOOL:
+          return "BOOLEAN";
+        case TDengineDataType.TSDB_DATA_TYPE_TINYINT:
+          return "BYTE";
+        case TDengineDataType.TSDB_DATA_TYPE_SMALLINT:
+          return "SHORT";
+        case TDengineDataType.TSDB_DATA_TYPE_INT:
+          return "INT";
+        case TDengineDataType.TSDB_DATA_TYPE_BIGINT:
+          return "LONG";
+        case TDengineDataType.TSDB_DATA_TYPE_FLOAT:
+          return "FLOAT";
+        case TDengineDataType.TSDB_DATA_TYPE_DOUBLE:
+          return "DOUBLE";
+        case TDengineDataType.TSDB_DATA_TYPE_BINARY:
+          return "STRING";
+        case TDengineDataType.TSDB_DATA_TYPE_TIMESTAMP:
+          return "TIMESTAMP";
+        case TDengineDataType.TSDB_DATA_TYPE_NCHAR:
+          return "NCHAR";
+        default:
+          return "undefine";
+      }
+    }
+  }
+
+  class TDengine
+  {
+    public const int TSDB_CODE_SUCCESS = 0;
+
+    [DllImport("taos.dll", EntryPoint = "taos_init", CallingConvention = CallingConvention.Cdecl)]
+    static extern public void Init();
+
+    [DllImport("taos.dll", EntryPoint = "taos_cleanup", CallingConvention = CallingConvention.Cdecl)]
+    static extern public void Cleanup();
+
+    [DllImport("taos.dll", EntryPoint = "taos_options", CallingConvention = CallingConvention.Cdecl)]
+    static extern public void Options(int option, string value);
+
+    [DllImport("taos.dll", EntryPoint = "taos_connect", CallingConvention = CallingConvention.Cdecl)]
+    static extern public IntPtr Connect(string ip, string user, string password, string db, short port);
+
+    [DllImport("taos.dll", EntryPoint = "taos_errstr", CallingConvention = CallingConvention.Cdecl)]
+    static extern private IntPtr taos_errstr(IntPtr res);
+    static public string Error(IntPtr res)
+    {
+      IntPtr errPtr = taos_errstr(res);
+      return Marshal.PtrToStringAnsi(errPtr);
+    }
+
+    [DllImport("taos.dll", EntryPoint = "taos_errno", CallingConvention = CallingConvention.Cdecl)]
+    static extern public int ErrorNo(IntPtr res);
+
+    [DllImport("taos.dll", EntryPoint = "taos_query", CallingConvention = CallingConvention.Cdecl)]
+    static extern public IntPtr Query(IntPtr conn, string sqlstr);
+
+    [DllImport("taos.dll", EntryPoint = "taos_affected_rows", CallingConvention = CallingConvention.Cdecl)]
+    static extern public int AffectRows(IntPtr res);
+
+    [DllImport("taos.dll", EntryPoint = "taos_field_count", CallingConvention = CallingConvention.Cdecl)]
+    static extern public int FieldCount(IntPtr res);
+
+    [DllImport("taos.dll", EntryPoint = "taos_fetch_fields", CallingConvention = CallingConvention.Cdecl)]
+    static extern private IntPtr taos_fetch_fields(IntPtr res);
+    static public List<TDengineMeta> FetchFields(IntPtr res)
+    {
+      const int fieldSize = 68;
+
+      List<TDengineMeta> metas = new List<TDengineMeta>();
+      if (res == IntPtr.Zero)
+      {
+        return metas;
+      }
+
+      int fieldCount = FieldCount(res);
+      IntPtr fieldsPtr = taos_fetch_fields(res);
+  
+      for (int i = 0; i < fieldCount; ++i)
+      {
+        int offset = i * fieldSize;
+        
+        TDengineMeta meta = new TDengineMeta();
+        meta.name = Marshal.PtrToStringAnsi(fieldsPtr + offset);
+        meta.type = Marshal.ReadByte(fieldsPtr + offset + 65);
+        meta.size = Marshal.ReadInt16(fieldsPtr + offset + 66);
+        metas.Add(meta);
+      }
+
+      return metas;
+    }
+
+    [DllImport("taos.dll", EntryPoint = "taos_fetch_row", CallingConvention = CallingConvention.Cdecl)]
+    static extern public IntPtr FetchRows(IntPtr res);
+
+    [DllImport("taos.dll", EntryPoint = "taos_free_result", CallingConvention = CallingConvention.Cdecl)]
+    static extern public IntPtr FreeResult(IntPtr res);
+
+    [DllImport("taos.dll", EntryPoint = "taos_close", CallingConvention = CallingConvention.Cdecl)]
+    static extern public int Close(IntPtr taos);
+  }
+}
\ No newline at end of file

src/util/src/tskiplist.c

@@ -24,8 +24,8 @@ static SSkipListNode *    getPriorNode(SSkipList *pSkipList, const char *val, in
 static void               tSkipListRemoveNodeImpl(SSkipList *pSkipList, SSkipListNode *pNode);
 static void               tSkipListCorrectLevel(SSkipList *pSkipList);
 static SSkipListIterator *doCreateSkipListIterator(SSkipList *pSkipList, int32_t order);
-static void               tSkipListDoInsert(SSkipList *pSkipList, SSkipListNode **forward, SSkipListNode *pNode);
-static bool               tSkipListGetPosToPut(SSkipList *pSkipList, SSkipListNode **forward, void *pData);
+static void               tSkipListDoInsert(SSkipList *pSkipList, SSkipListNode **backward, SSkipListNode *pNode);
+static bool               tSkipListGetPosToPut(SSkipList *pSkipList, SSkipListNode **backward, void *pData);
 static SSkipListNode *    tSkipListNewNode(uint8_t level);
 #define tSkipListFreeNode(n) tfree((n))
 
@@ -108,17 +108,17 @@ void tSkipListDestroy(SSkipList *pSkipList) {
 SSkipListNode *tSkipListPut(SSkipList *pSkipList, void *pData) {
   if (pSkipList == NULL || pData == NULL) return NULL;
 
-  SSkipListNode *forward[MAX_SKIP_LIST_LEVEL] = {0};
+  SSkipListNode *backward[MAX_SKIP_LIST_LEVEL] = {0};
   uint8_t        dupMode = SL_DUP_MODE(pSkipList);
   SSkipListNode *pNode = NULL;
 
   tSkipListWLock(pSkipList);
 
-  bool hasDup = tSkipListGetPosToPut(pSkipList, forward, pData);
+  bool hasDup = tSkipListGetPosToPut(pSkipList, backward, pData);
 
   if (hasDup && (dupMode == SL_DISCARD_DUP_KEY || dupMode == SL_UPDATE_DUP_KEY)) {
     if (dupMode == SL_UPDATE_DUP_KEY) {
-      pNode = SL_NODE_GET_FORWARD_POINTER(forward[0], 0);
+      pNode = SL_NODE_GET_BACKWARD_POINTER(backward[0], 0);
       atomic_store_ptr(&(pNode->pData), pData);
     }
   } else {
@@ -126,7 +126,7 @@ SSkipListNode *tSkipListPut(SSkipList *pSkipList, void *pData) {
     if (pNode != NULL) {
       pNode->pData = pData;
 
-      tSkipListDoInsert(pSkipList, forward, pNode);
+      tSkipListDoInsert(pSkipList, backward, pNode);
     }
   }
 
@@ -310,7 +310,7 @@ void tSkipListPrint(SSkipList *pSkipList, int16_t nlevel) {
   }
 }
 
-static void tSkipListDoInsert(SSkipList *pSkipList, SSkipListNode **forward, SSkipListNode *pNode) {
+static void tSkipListDoInsert(SSkipList *pSkipList, SSkipListNode **backward, SSkipListNode *pNode) {
   for (int32_t i = 0; i < pNode->level; ++i) {
     if (i >= pSkipList->level) {
       SL_NODE_GET_FORWARD_POINTER(pNode, i) = pSkipList->pTail;
@@ -318,14 +318,14 @@ static void tSkipListDoInsert(SSkipList *pSkipList, SSkipListNode **forward, SSk
       SL_NODE_GET_FORWARD_POINTER(pSkipList->pHead, i) = pNode;
       SL_NODE_GET_BACKWARD_POINTER(pSkipList->pTail, i) = pNode;
     } else {
-      SSkipListNode *x = forward[i];
-      SL_NODE_GET_BACKWARD_POINTER(pNode, i) = x;
+      SSkipListNode *x = backward[i];
+      SL_NODE_GET_FORWARD_POINTER(pNode, i) = x;
 
-      SSkipListNode *next = SL_NODE_GET_FORWARD_POINTER(x, i);
-      SL_NODE_GET_BACKWARD_POINTER(next, i) = pNode;
+      SSkipListNode *prev = SL_NODE_GET_BACKWARD_POINTER(x, i);
+      SL_NODE_GET_FORWARD_POINTER(prev, i) = pNode;
 
-      SL_NODE_GET_FORWARD_POINTER(pNode, i) = next;
-      SL_NODE_GET_FORWARD_POINTER(x, i) = pNode;
+      SL_NODE_GET_BACKWARD_POINTER(x, i) = pNode;
+      SL_NODE_GET_BACKWARD_POINTER(pNode, i) = prev;
     }
   }
 
@@ -371,57 +371,57 @@ static FORCE_INLINE int tSkipListUnlock(SSkipList *pSkipList) {
   return 0;
 }
 
-static bool tSkipListGetPosToPut(SSkipList *pSkipList, SSkipListNode **forward, void *pData) {
+static bool tSkipListGetPosToPut(SSkipList *pSkipList, SSkipListNode **backward, void *pData) {
   int     compare = 0;
   bool    hasDupKey = false;
   char *  pDataKey = pSkipList->keyFn(pData);
 
   if (pSkipList->size == 0) {
     for (int i = 0; i < pSkipList->level; i++) {
-      forward[i] = pSkipList->pHead;
+      backward[i] = pSkipList->pTail;
     }
   } else {
     char *pKey = NULL;
 
-    // Compare min key
-    pKey = SL_GET_MIN_KEY(pSkipList);
+    // Compare max key
+    pKey = SL_GET_MAX_KEY(pSkipList);
     compare = pSkipList->comparFn(pDataKey, pKey);
-    if (compare <= 0) {
+    if (compare >= 0) {
       for (int i = 0; i < pSkipList->level; i++) {
-        forward[i] = pSkipList->pHead;
+        backward[i] = pSkipList->pTail;
       }
 
       return (compare == 0);
     }
 
-    // Compare max key
-    pKey = SL_GET_MAX_KEY(pSkipList);
+    // Compare min key
+    pKey = SL_GET_MIN_KEY(pSkipList);
     compare = pSkipList->comparFn(pDataKey, pKey);
-    if (compare > 0) {
+    if (compare < 0) {
       for (int i = 0; i < pSkipList->level; i++) {
-        forward[i] = SL_NODE_GET_BACKWARD_POINTER(pSkipList->pTail, i);
+        backward[i] = SL_NODE_GET_FORWARD_POINTER(pSkipList->pHead, i);
       }
 
       return (compare == 0);
     }
 
-    SSkipListNode *px = pSkipList->pHead;
+    SSkipListNode *px = pSkipList->pTail;
     for (int i = pSkipList->level - 1; i >= 0; --i) {
-      SSkipListNode *p = SL_NODE_GET_FORWARD_POINTER(px, i);
-      while (p != pSkipList->pTail) {
+      SSkipListNode *p = SL_NODE_GET_BACKWARD_POINTER(px, i);
+      while (p != pSkipList->pHead) {
         pKey = SL_GET_NODE_KEY(pSkipList, p);
 
         compare = pSkipList->comparFn(pKey, pDataKey);
-        if (compare >= 0) {
+        if (compare <= 0) {
           if (compare == 0 && !hasDupKey) hasDupKey = true;
           break;
         } else {
           px = p;
-          p = SL_NODE_GET_FORWARD_POINTER(px, i);
+          p = SL_NODE_GET_BACKWARD_POINTER(px, i);
         }
       }
 
-      forward[i] = px;
+      backward[i] = px;
     }
   }
 

tests/pytest/query/bug1874.py

+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+from util.log import *
+from util.cases import *
+from util.sql import *
+from util.dnodes import *
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+    def run(self):
+        tdSql.prepare()
+        print("==========step1")
+        print("create table && insert data")
+        
+        tdSql.execute("create table join_mt0 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) TAGS(t1 int, t2 binary(12))")
+        tdSql.execute("create table join_mt1 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) TAGS(t1 int, t2 binary(12))")
+        stable=0
+        insertRows = 1000
+        tbnum = 3
+        t0 = 1604298064000
+        tdLog.info("insert %d rows" % (insertRows))
+        for i in range(tbnum):
+            tdSql.execute("create table join_tb%d using join_mt%d tags(%d,'abc')" %(i,stable,i))
+            for j in range(insertRows):
+                ret = tdSql.execute(
+                    "insert into join_tb%d values (%d , %d,%d,%d,%d,%d,%d,%d, '%s','%s')" %
+                    (i,t0+i,i%100,i%100,i%100,i%100,i%100,i%100,i%100,'binary'+str(i%100),'nchar'+str(i%100)))
+        stable=stable+1
+        for i in range(tbnum):
+            tdSql.execute("create table join_1_tb%d using join_mt%d tags(%d,'abc')" %(i,stable,i))
+            for j in range(insertRows):
+                ret = tdSql.execute(
+                    "insert into join_tb%d values (%d , %d,%d,%d,%d,%d,%d,%d, '%s','%s')" %
+                    (i,t0+i,i%100,i%100,i%100,i%100,i%100,i%100,i%100,'binary'+str(i%100),'nchar'+str(i%100)))
+        print("==========step2")
+        print("join query ")
+        tdLog.info("select count(join_mt0.c1), first(join_mt0.c1) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2, join_mt1.t1 order by join_mt0.ts desc, join_mt1.ts asc limit 10;")
+        tdSql.error("select count(join_mt0.c1), first(join_mt0.c1) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2, join_mt1.t1 order by join_mt0.ts desc, join_mt1.ts asc limit 10;")
+        
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file

tests/pytest/query/bug1875.py

+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+from util.log import *
+from util.cases import *
+from util.sql import *
+from util.dnodes import *
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+    def run(self):
+        tdSql.prepare()
+        print("==========step1")
+        print("create table && insert data")
+        
+        tdSql.execute("create table join_mt0 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) TAGS(t1 int, t2 binary(12))")
+        tdSql.execute("create table join_mt1 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) TAGS(t1 int, t2 binary(12))")
+        stable=0
+        insertRows = 1000
+        tbnum = 3
+        t0 = 1604298064000
+        tdLog.info("insert %d rows" % (insertRows))
+        for i in range(tbnum):
+            tdSql.execute("create table join_tb%d using join_mt%d tags(%d,'abc')" %(i,stable,i))
+            for j in range(insertRows):
+                ret = tdSql.execute(
+                    "insert into join_tb%d values (%d , %d,%d,%d,%d,%d,%d,%d, '%s','%s')" %
+                    (i,t0+i,i%100,i%100,i%100,i%100,i%100,i%100,i%100,'binary'+str(i%100),'nchar'+str(i%100)))
+        stable=stable+1
+        for i in range(tbnum):
+            tdSql.execute("create table join_1_tb%d using join_mt%d tags(%d,'abc')" %(i,stable,i))
+            for j in range(insertRows):
+                ret = tdSql.execute(
+                    "insert into join_tb%d values (%d , %d,%d,%d,%d,%d,%d,%d, '%s','%s')" %
+                    (i,t0+i,i%100,i%100,i%100,i%100,i%100,i%100,i%100,'binary'+str(i%100),'nchar'+str(i%100)))
+        print("==========step2")
+        print("join query ")
+        tdLog.info("select count(join_mt0.c1), first(join_mt0.c1) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2, join_mt1.t1 order by join_mt0.ts desc, join_mt1.ts asc limit 10;")
+        tdSql.error("select count(join_mt0.c1), first(join_mt0.c1), first(join_mt1.c9) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2 order by join_mt0.t1 desc")
+        tdSql.error("select count(join_mt0.c1), first(join_mt0.c1), first(join_mt1.c9) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2 order by join_mt0.t1 desc limit 3;")
+        tdSql.error("select count(join_mt0.c1), first(join_mt0.c1), first(join_mt1.c9) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2 order by join_mt0.t1 desc slimit 3;")
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file

tests/pytest/query/bug1876.py

+###################################################################
+#           Copyright (c) 2016 by TAOS Technologies, Inc.
+#                     All rights reserved.
+#
+#  This file is proprietary and confidential to TAOS Technologies.
+#  No part of this file may be reproduced, stored, transmitted,
+#  disclosed or used in any form or by any means other than as
+#  expressly provided by the written permission from Jianhui Tao
+#
+###################################################################
+
+# -*- coding: utf-8 -*-
+
+import sys
+from util.log import *
+from util.cases import *
+from util.sql import *
+from util.dnodes import *
+class TDTestCase:
+    def init(self, conn, logSql):
+        tdLog.debug("start to execute %s" % __file__)
+        tdSql.init(conn.cursor(), logSql)
+
+    def run(self):
+        tdSql.prepare()
+        print("==========step1")
+        print("create table && insert data")
+        
+        tdSql.execute("create table join_mt0 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) TAGS(t1 int, t2 binary(12))")
+        tdSql.execute("create table join_mt1 (ts timestamp, c1 int, c2 float, c3 bigint, c4 smallint, c5 tinyint, c6 double, c7 bool, c8 binary(10), c9 nchar(9)) TAGS(t1 int, t2 binary(12))")
+        stable=0
+        insertRows = 1000
+        tbnum = 3
+        t0 = 1604298064000
+        tdLog.info("insert %d rows" % (insertRows))
+        for i in range(tbnum):
+            tdSql.execute("create table join_tb%d using join_mt%d tags(%d,'abc')" %(i,stable,i))
+            for j in range(insertRows):
+                ret = tdSql.execute(
+                    "insert into join_tb%d values (%d , %d,%d,%d,%d,%d,%d,%d, '%s','%s')" %
+                    (i,t0+i,i%100,i%100,i%100,i%100,i%100,i%100,i%100,'binary'+str(i%100),'nchar'+str(i%100)))
+        stable=stable+1
+        for i in range(tbnum):
+            tdSql.execute("create table join_1_tb%d using join_mt%d tags(%d,'abc')" %(i,stable,i))
+            for j in range(insertRows):
+                ret = tdSql.execute(
+                    "insert into join_tb%d values (%d , %d,%d,%d,%d,%d,%d,%d, '%s','%s')" %
+                    (i,t0+i,i%100,i%100,i%100,i%100,i%100,i%100,i%100,'binary'+str(i%100),'nchar'+str(i%100)))
+        print("==========step2")
+        print("join query ")
+        tdLog.info("select count(join_mt0.c1), first(join_mt0.c1) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts interval(10a) group by join_mt0.t1, join_mt0.t2, join_mt1.t1 order by join_mt0.ts desc, join_mt1.ts asc limit 10;")
+        tdSql.error("select count(join_mt0.c1), first(join_mt0.c1)-first(join_mt1.c1), first(join_mt1.c9) from join_mt0, join_mt1 where join_mt0.t1=join_mt1.t1 and join_mt0.ts=join_mt1.ts;")
+    def stop(self):
+        tdSql.close()
+        tdLog.success("%s successfully executed" % __file__)
+
+tdCases.addWindows(__file__, TDTestCase())
+tdCases.addLinux(__file__, TDTestCase())
\ No newline at end of file