diff --git a/include/libs/planner/planner.h b/include/libs/planner/planner.h
index 844757eeb5b4bacbeca03cf28eecc803f7924b90..a7d418d45e5dd2093188a5340ab241619623b3c8 100644
--- a/include/libs/planner/planner.h
+++ b/include/libs/planner/planner.h
@@ -84,8 +84,8 @@ typedef struct SProjectPhyNode {
 
 typedef struct SExchangePhyNode {
   SPhyNode    node;
-  uint64_t    templateId;
-  SArray     *pSourceEpSet;  // SEpSet
+  uint64_t    srcTemplateId; // template id of datasource suplans
+  SArray     *pSourceEpSet;  // SEpSet, scheduler fill by calling qSetSuplanExecutionNode
 } SExchangePhyNode;
 
 typedef struct SSubplanId {
@@ -113,6 +113,8 @@ typedef struct SQueryDag {
  */
 int32_t qCreateQueryDag(const struct SQueryStmtInfo* pQueryInfo, struct SEpSet* pQnode, struct SQueryDag** pDag);
 
+int32_t qSetSuplanExecutionNode(SArray* subplans, SArray* nodes);
+
 int32_t qExplainQuery(const struct SQueryStmtInfo* pQueryInfo, struct SEpSet* pQnode, char** str);
 
 
@@ -126,7 +128,7 @@ int32_t qSubPlanToString(struct SSubplan *pPhyNode, char** str);
  * @param pQueryPhyNode
  * @return
  */
-void* qDestroyQueryDag(struct SQueryDag* pDag);
+void qDestroyQueryDag(struct SQueryDag* pDag);
 
 #ifdef __cplusplus
 }
diff --git a/include/libs/planner/plannerOp.h b/include/libs/planner/plannerOp.h
index 27c7c534a25235f3f902adab57d08870fb3cb2cf..9f51969dc1d00028a3fcf6a508966d7e787bdcb5 100644
--- a/include/libs/planner/plannerOp.h
+++ b/include/libs/planner/plannerOp.h
@@ -27,7 +27,7 @@ OP_ENUM_MACRO(TableScan)
 OP_ENUM_MACRO(DataBlocksOptScan)
 OP_ENUM_MACRO(TableSeqScan)
 OP_ENUM_MACRO(TagScan)
-OP_ENUM_MACRO(TableBlockInfoScan)
+OP_ENUM_MACRO(SystemTableScan)
 OP_ENUM_MACRO(Aggregate)
 OP_ENUM_MACRO(Project)
 OP_ENUM_MACRO(Groupby)
diff --git a/source/libs/planner/inc/plannerInt.h b/source/libs/planner/inc/plannerInt.h
index 6c65e4810df4dc177963a868c438a827aad80103..38b399fb0bdc388e18f103b385b453649f34eb0b 100644
--- a/source/libs/planner/inc/plannerInt.h
+++ b/source/libs/planner/inc/plannerInt.h
@@ -99,6 +99,8 @@ int32_t queryPlanToString(struct SQueryPlanNode* pQueryNode, char** str);
  */
 int32_t queryPlanToSql(struct SQueryPlanNode* pQueryNode, char** sql);
 
+int32_t createDag(SQueryPlanNode* pQueryNode, struct SCatalog* pCatalog, SQueryDag** pDag);
+
 /**
  * Convert to physical plan to string to enable to print it out in the shell.
  * @param pPhyNode
@@ -111,7 +113,7 @@ int32_t phyPlanToString(struct SPhyNode *pPhyNode, char** str);
  * Destroy the query plan object.
  * @return
  */
-void* destroyQueryPlan(struct SQueryPlanNode* pQueryNode);
+void destroyQueryPlan(struct SQueryPlanNode* pQueryNode);
 
 /**
  * Destroy the physical plan.
diff --git a/source/libs/planner/src/logicPlan.c b/source/libs/planner/src/logicPlan.c
new file mode 100644
index 0000000000000000000000000000000000000000..ce923314bd9530b6425fff926cb3b9662f57b813
--- /dev/null
+++ b/source/libs/planner/src/logicPlan.c
@@ -0,0 +1,604 @@
+/*
+ * 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/>.
+ */
+
+#include "function.h"
+#include "os.h"
+#include "parser.h"
+#include "plannerInt.h"
+
+typedef struct SFillEssInfo {
+  int32_t  fillType;  // fill type
+  int64_t *val;       // fill value
+} SFillEssInfo;
+
+typedef struct SJoinCond {
+  bool     tagExists; // denote if tag condition exists or not
+  SColumn *tagCond[2];
+  SColumn *colCond[2];
+} SJoinCond;
+
+static SArray* createQueryPlanImpl(SQueryStmtInfo* pQueryInfo);
+static void doDestroyQueryNode(SQueryPlanNode* pQueryNode);
+
+int32_t printExprInfo(char* buf, const SQueryPlanNode* pQueryNode, int32_t len);
+int32_t optimizeQueryPlan(struct SQueryPlanNode* pQueryNode) {
+  return 0;
+}
+
+int32_t createQueryPlan(const struct SQueryStmtInfo* pQueryInfo, struct SQueryPlanNode** pQueryNode) {
+  SArray* upstream = createQueryPlanImpl((struct SQueryStmtInfo*) pQueryInfo);
+  assert(taosArrayGetSize(upstream) == 1);
+
+  *pQueryNode = taosArrayGetP(upstream, 0);
+
+  taosArrayDestroy(upstream);
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t queryPlanToSql(struct SQueryPlanNode* pQueryNode, char** sql) {
+  return 0;
+}
+
+void destroyQueryPlan(SQueryPlanNode* pQueryNode) {
+  if (pQueryNode == NULL) {
+    return;
+  }
+
+  doDestroyQueryNode(pQueryNode);
+}
+
+//======================================================================================================================
+
+static SQueryPlanNode* createQueryNode(int32_t type, const char* name, SQueryPlanNode** prev, int32_t numOfPrev,
+                                   SExprInfo** pExpr, int32_t numOfOutput, void* pExtInfo) {
+  SQueryPlanNode* pNode = calloc(1, sizeof(SQueryPlanNode));
+
+  pNode->info.type = type;
+  pNode->info.name = strdup(name);
+
+  pNode->numOfExpr = numOfOutput;
+  pNode->pExpr = taosArrayInit(numOfOutput, POINTER_BYTES);
+
+  for(int32_t i = 0; i < numOfOutput; ++i) {
+    taosArrayPush(pNode->pExpr, &pExpr[i]);
+  }
+
+  pNode->pChildren = taosArrayInit(4, POINTER_BYTES);
+  for(int32_t i = 0; i < numOfPrev; ++i) {
+    taosArrayPush(pNode->pChildren, &prev[i]);
+  }
+
+  switch(type) {
+    case QNODE_TAGSCAN:
+    case QNODE_TABLESCAN: {
+      SQueryTableInfo* info = calloc(1, sizeof(SQueryTableInfo));
+      memcpy(info, pExtInfo, sizeof(SQueryTableInfo));
+      info->tableName = strdup(((SQueryTableInfo*) pExtInfo)->tableName);
+      pNode->pExtInfo = info;
+      break;
+    }
+
+    case QNODE_TIMEWINDOW: {
+      SInterval* pInterval = calloc(1, sizeof(SInterval));
+      pNode->pExtInfo = pInterval;
+      memcpy(pInterval, pExtInfo, sizeof(SInterval));
+      break;
+    }
+
+    case QNODE_STATEWINDOW: {
+      SColumn* psw = calloc(1, sizeof(SColumn));
+      pNode->pExtInfo = psw;
+      memcpy(psw, pExtInfo, sizeof(SColumn));
+      break;
+    }
+
+    case QNODE_SESSIONWINDOW: {
+      SSessionWindow *pSessionWindow = calloc(1, sizeof(SSessionWindow));
+      pNode->pExtInfo = pSessionWindow;
+      memcpy(pSessionWindow, pExtInfo, sizeof(struct SSessionWindow));
+      break;
+    }
+
+    case QNODE_GROUPBY: {
+      SGroupbyExpr* p = (SGroupbyExpr*) pExtInfo;
+
+      SGroupbyExpr* pGroupbyExpr = calloc(1, sizeof(SGroupbyExpr));
+      pGroupbyExpr->groupbyTag = p->groupbyTag;
+      pGroupbyExpr->columnInfo = taosArrayDup(p->columnInfo);
+
+      pNode->pExtInfo = pGroupbyExpr;
+      break;
+    }
+
+    case QNODE_FILL: { // todo !!
+      pNode->pExtInfo = pExtInfo;
+      break;
+    }
+
+    case QNODE_LIMIT: {
+      pNode->pExtInfo = calloc(1, sizeof(SLimit));
+      memcpy(pNode->pExtInfo, pExtInfo, sizeof(SLimit));
+      break;
+    }
+
+    case QNODE_SORT: {
+      pNode->pExtInfo = taosArrayDup(pExtInfo);
+      break;
+    }
+
+    default:
+      break;
+  }
+  
+  return pNode;
+}
+
+static SQueryPlanNode* doAddTableColumnNode(SQueryStmtInfo* pQueryInfo, STableMetaInfo* pTableMetaInfo, SQueryTableInfo* info,
+                                        SArray* pExprs, SArray* tableCols) {
+  if (pQueryInfo->info.onlyTagQuery) {
+    int32_t num = (int32_t) taosArrayGetSize(pExprs);
+    SQueryPlanNode* pNode = createQueryNode(QNODE_TAGSCAN, "TableTagScan", NULL, 0, pExprs->pData, num, info);
+
+    if (pQueryInfo->info.distinct) {
+      pNode = createQueryNode(QNODE_DISTINCT, "Distinct", &pNode, 1, pExprs->pData, num, NULL);
+    }
+
+    return pNode;
+  }
+
+  SQueryPlanNode*  pNode = createQueryNode(QNODE_TABLESCAN, "TableScan", NULL, 0, NULL, 0, info);
+
+  if (pQueryInfo->info.projectionQuery) {
+    int32_t numOfOutput = (int32_t) taosArrayGetSize(pExprs);
+    pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, pExprs->pData, numOfOutput, NULL);
+  } else {
+    STableMetaInfo* pTableMetaInfo1 = getMetaInfo(pQueryInfo, 0);
+
+    // table source column projection, generate the projection expr
+    int32_t     numOfCols = (int32_t) taosArrayGetSize(tableCols);
+    SExprInfo** pExpr = calloc(numOfCols, POINTER_BYTES);
+    for (int32_t i = 0; i < numOfCols; ++i) {
+      SColumn* pCol = taosArrayGetP(tableCols, i);
+
+      SSourceParam param = {0};
+      addIntoSourceParam(&param, NULL, pCol);
+      SSchema s = createSchema(pCol->info.type, pCol->info.bytes, pCol->info.colId, pCol->name);
+      SExprInfo* p = createExprInfo(pTableMetaInfo1, "project", &param, &s, 0);
+      pExpr[i] = p;
+    }
+
+    pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, pExpr, numOfCols, NULL);
+    tfree(pExpr);
+  }
+
+  return pNode;
+}
+
+static SQueryPlanNode* doCreateQueryPlanForSingleTableImpl(SQueryStmtInfo* pQueryInfo, SQueryPlanNode* pNode, SQueryTableInfo* info) {
+  // group by column not by tag
+  size_t numOfGroupCols = taosArrayGetSize(pQueryInfo->groupbyExpr.columnInfo);
+
+  // check for aggregation
+  int32_t level = getExprFunctionLevel(pQueryInfo);
+
+  for(int32_t i = level - 1; i >= 0; --i) {
+    SArray* p = pQueryInfo->exprList[i];
+    size_t  num = taosArrayGetSize(p);
+
+    bool aggregateFunc = false;
+    for(int32_t j = 0; j < num; ++j) {
+      SExprInfo* pExpr = (SExprInfo*)taosArrayGetP(p, 0);
+      if (pExpr->pExpr->nodeType != TEXPR_FUNCTION_NODE) {
+        continue;
+      }
+
+      aggregateFunc = qIsAggregateFunction(pExpr->pExpr->_function.functionName);
+      if (aggregateFunc) {
+        break;
+      }
+    }
+
+    if (aggregateFunc) {
+      if (pQueryInfo->interval.interval > 0) {
+        pNode = createQueryNode(QNODE_TIMEWINDOW, "TimeWindowAgg", &pNode, 1, p->pData, num, &pQueryInfo->interval);
+      } else if (pQueryInfo->sessionWindow.gap > 0) {
+        pNode = createQueryNode(QNODE_SESSIONWINDOW, "SessionWindowAgg", &pNode, 1, p->pData, num, &pQueryInfo->sessionWindow);
+      } else if (pQueryInfo->stateWindow.col.info.colId > 0) {
+        pNode = createQueryNode(QNODE_STATEWINDOW, "StateWindowAgg", &pNode, 1, p->pData, num, &pQueryInfo->stateWindow);
+      } else if (numOfGroupCols != 0 && !pQueryInfo->groupbyExpr.groupbyTag) {
+          pNode = createQueryNode(QNODE_GROUPBY, "Groupby", &pNode, 1, p->pData, num, &pQueryInfo->groupbyExpr);
+      } else {
+        pNode = createQueryNode(QNODE_AGGREGATE, "Aggregate", &pNode, 1, p->pData, num, NULL);
+      }
+    } else {
+      pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, p->pData, num, NULL);
+    }
+  }
+
+  if (pQueryInfo->havingFieldNum > 0) {
+//    int32_t numOfExpr = (int32_t)taosArrayGetSize(pQueryInfo->exprList1);
+//    pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, pQueryInfo->exprList1->pData, numOfExpr, NULL);
+  }
+
+  if (pQueryInfo->fillType != TSDB_FILL_NONE) {
+    SFillEssInfo* pInfo = calloc(1, sizeof(SFillEssInfo));
+    pInfo->fillType = pQueryInfo->fillType;
+    pInfo->val      = calloc(pNode->numOfExpr, sizeof(int64_t));
+    memcpy(pInfo->val, pQueryInfo->fillVal, pNode->numOfExpr);
+
+    SArray* p = pQueryInfo->exprList[0];  // top expression in select clause
+    pNode = createQueryNode(QNODE_FILL, "Fill", &pNode, 1, p, taosArrayGetSize(p), pInfo);
+  }
+
+  if (pQueryInfo->order != NULL) {
+    SArray* pList = pQueryInfo->exprList[0];
+    pNode = createQueryNode(QNODE_SORT, "Sort", &pNode, 1, pList->pData, taosArrayGetSize(pList), pQueryInfo->order);
+  }
+
+  if (pQueryInfo->limit.limit != -1 || pQueryInfo->limit.offset != 0) {
+    pNode = createQueryNode(QNODE_LIMIT, "Limit", &pNode, 1, NULL, 0, &pQueryInfo->limit);
+  }
+
+  return pNode;
+}
+
+static SQueryPlanNode* doCreateQueryPlanForSingleTable(SQueryStmtInfo* pQueryInfo, STableMetaInfo* pTableMetaInfo, SArray* pExprs,
+                                                SArray* tableCols) {
+  char name[TSDB_TABLE_FNAME_LEN] = {0};
+  tstrncpy(name, pTableMetaInfo->name.tname, TSDB_TABLE_FNAME_LEN);
+
+  SQueryTableInfo info = {.tableName = strdup(name), .uid = pTableMetaInfo->pTableMeta->uid,};
+
+  // handle the only tag query
+  SQueryPlanNode* pNode = doAddTableColumnNode(pQueryInfo, pTableMetaInfo, &info, pExprs, tableCols);
+  if (pQueryInfo->info.onlyTagQuery) {
+    tfree(info.tableName);
+    return pNode;
+  }
+
+  SQueryPlanNode* pNode1 = doCreateQueryPlanForSingleTableImpl(pQueryInfo, pNode, &info);
+  tfree(info.tableName);
+  return pNode1;
+}
+
+static bool isAllAggExpr(SArray* pList) {
+  assert(pList != NULL);
+
+  for (int32_t k = 0; k < taosArrayGetSize(pList); ++k) {
+    SExprInfo* p = taosArrayGetP(pList, k);
+    if (p->pExpr->nodeType != TEXPR_FUNCTION_NODE || !qIsAggregateFunction(p->pExpr->_function.functionName)) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+SArray* createQueryPlanImpl(SQueryStmtInfo* pQueryInfo) {
+  SArray* upstream = NULL;
+
+  if (pQueryInfo->pUpstream != NULL && taosArrayGetSize(pQueryInfo->pUpstream) > 0) {  // subquery in the from clause
+    upstream = taosArrayInit(4, POINTER_BYTES);
+
+    size_t size = taosArrayGetSize(pQueryInfo->pUpstream);
+    for(int32_t i = 0; i < size; ++i) {
+      SQueryStmtInfo* pq = taosArrayGet(pQueryInfo->pUpstream, i);
+      SArray* p = createQueryPlanImpl(pq);
+      taosArrayAddBatch(upstream, p->pData, (int32_t) taosArrayGetSize(p));
+    }
+  }
+
+  if (pQueryInfo->numOfTables > 1) {  // it is a join query
+    // 1. separate the select clause according to table
+    taosArrayDestroy(upstream);
+    upstream = taosArrayInit(5, POINTER_BYTES);
+
+    for(int32_t i = 0; i < pQueryInfo->numOfTables; ++i) {
+      STableMetaInfo* pTableMetaInfo = pQueryInfo->pTableMetaInfo[i];
+      uint64_t        uid = pTableMetaInfo->pTableMeta->uid;
+
+      SArray* exprList = taosArrayInit(4, POINTER_BYTES);
+      if (copyExprInfoList(exprList, pQueryInfo->exprList[0], uid, true) != 0) {
+        terrno = TSDB_CODE_TSC_OUT_OF_MEMORY;
+//        dropAllExprInfo(exprList);
+        exit(-1);
+      }
+
+      // 2. create the query execution node
+      char name[TSDB_TABLE_FNAME_LEN] = {0};
+      tNameExtractFullName(&pTableMetaInfo->name, name);
+      SQueryTableInfo info = {.tableName = strdup(name), .uid = pTableMetaInfo->pTableMeta->uid,};
+
+      // 3. get the required table column list
+      SArray* tableColumnList = taosArrayInit(4, sizeof(SColumn));
+      columnListCopy(tableColumnList, pQueryInfo->colList, uid);
+
+      // 4. add the projection query node
+      SQueryPlanNode* pNode = doAddTableColumnNode(pQueryInfo, pTableMetaInfo, &info, exprList, tableColumnList);
+      columnListDestroy(tableColumnList);
+//      dropAllExprInfo(exprList);
+      taosArrayPush(upstream, &pNode);
+    }
+
+    // 3. add the join node here
+    SQueryTableInfo info = {0};
+    int32_t num = (int32_t) taosArrayGetSize(pQueryInfo->exprList[0]);
+    SQueryPlanNode* pNode = createQueryNode(QNODE_JOIN, "Join", upstream->pData, pQueryInfo->numOfTables,
+                                        pQueryInfo->exprList[0]->pData, num, NULL);
+
+    // 4. add the aggregation or projection execution node
+    pNode = doCreateQueryPlanForSingleTableImpl(pQueryInfo, pNode, &info);
+    upstream = taosArrayInit(5, POINTER_BYTES);
+    taosArrayPush(upstream, &pNode);
+  } else { // only one table, normal query process
+    STableMetaInfo* pTableMetaInfo = pQueryInfo->pTableMetaInfo[0];
+    SQueryPlanNode* pNode = doCreateQueryPlanForSingleTable(pQueryInfo, pTableMetaInfo, pQueryInfo->exprList[0], pQueryInfo->colList);
+    upstream = taosArrayInit(5, POINTER_BYTES);
+    taosArrayPush(upstream, &pNode);
+  }
+
+  return upstream;
+}
+
+static void doDestroyQueryNode(SQueryPlanNode* pQueryNode) {
+  tfree(pQueryNode->pExtInfo);
+  tfree(pQueryNode->pSchema);
+  tfree(pQueryNode->info.name);
+//  dropAllExprInfo(pQueryNode->pExpr);
+
+  if (pQueryNode->pChildren != NULL) {
+    int32_t size = (int32_t) taosArrayGetSize(pQueryNode->pChildren);
+    for(int32_t i = 0; i < size; ++i) {
+      SQueryPlanNode* p = taosArrayGetP(pQueryNode->pChildren, i);
+      doDestroyQueryNode(p);
+    }
+
+    taosArrayDestroy(pQueryNode->pChildren);
+  }
+
+  tfree(pQueryNode);
+}
+
+static int32_t doPrintPlan(char* buf, SQueryPlanNode* pQueryNode, int32_t level, int32_t totalLen) {
+  if (level > 0) {
+    sprintf(buf + totalLen, "%*c", level, ' ');
+    totalLen += level;
+  }
+
+  int32_t len1 = sprintf(buf + totalLen, "%s(", pQueryNode->info.name);
+  int32_t len = len1 + totalLen;
+
+  switch(pQueryNode->info.type) {
+    case QNODE_TABLESCAN: {
+      SQueryTableInfo* pInfo = (SQueryTableInfo*)pQueryNode->pExtInfo;
+      len1 = sprintf(buf + len, "%s #%" PRIu64 ") time_range: %" PRId64 " - %" PRId64, pInfo->tableName, pInfo->uid,
+                     pInfo->window.skey, pInfo->window.ekey);
+      assert(len1 > 0);
+      len += len1;
+
+      for (int32_t i = 0; i < pQueryNode->numOfExpr; ++i) {
+        SColumn* pCol = taosArrayGetP(pQueryNode->pExpr, i);
+        len1 = sprintf(buf + len, " [%s #%d] ", pCol->name, pCol->info.colId);
+
+        assert(len1 > 0);
+        len += len1;
+      }
+
+      len1 = sprintf(buf + len, "\n");
+      assert(len1 > 0);
+
+      len += len1;
+      break;
+    }
+
+    case QNODE_PROJECT: {
+      len1 = sprintf(buf + len, "cols:");
+      assert(len1 > 0);
+      len += len1;
+
+      len = printExprInfo(buf, pQueryNode, len);
+      len1 = sprintf(buf + len, ")");
+      len += len1;
+
+      // todo print filter info
+      len1 = sprintf(buf + len, " filters:(nil)\n");
+      len += len1;
+      break;
+    }
+
+    case QNODE_AGGREGATE: {
+      len = printExprInfo(buf, pQueryNode, len);
+      len1 = sprintf(buf + len, ")\n");
+      len += len1;
+
+      break;
+    }
+
+    case QNODE_TIMEWINDOW: {
+      len = printExprInfo(buf, pQueryNode, len);
+      len1 = sprintf(buf + len, ") ");
+      len += len1;
+
+      SInterval* pInterval = pQueryNode->pExtInfo;
+
+      // todo dynamic return the time precision
+      len1 = sprintf(buf + len, "interval:%" PRId64 "(%s), sliding:%" PRId64 "(%s), offset:%" PRId64 "(%s)\n",
+                     pInterval->interval, TSDB_TIME_PRECISION_MILLI_STR, pInterval->sliding,
+                     TSDB_TIME_PRECISION_MILLI_STR, pInterval->offset, TSDB_TIME_PRECISION_MILLI_STR);
+      len += len1;
+
+      break;
+    }
+
+    case QNODE_STATEWINDOW: {
+      len = printExprInfo(buf, pQueryNode, len);
+      len1 = sprintf(buf + len, ") ");
+      len += len1;
+
+      SColumn* pCol = pQueryNode->pExtInfo;
+      len1 = sprintf(buf + len, "col:%s #%d\n", pCol->name, pCol->info.colId);
+      len += len1;
+      break;
+    }
+
+    case QNODE_SESSIONWINDOW: {
+      len = printExprInfo(buf, pQueryNode, len);
+
+      len1 = sprintf(buf + len, ") ");
+      len += len1;
+
+      struct SSessionWindow* ps = pQueryNode->pExtInfo;
+      len1 = sprintf(buf + len, "col:[%s #%d], gap:%" PRId64 " (ms) \n", ps->col.name, ps->col.info.colId, ps->gap);
+      len += len1;
+      break;
+    }
+
+    case QNODE_GROUPBY: {
+      len = printExprInfo(buf, pQueryNode, len);
+
+      SGroupbyExpr* pGroupbyExpr = pQueryNode->pExtInfo;
+      len1 = sprintf(buf + len, ") groupby_col: ");
+      len += len1;
+
+      for (int32_t i = 0; i < taosArrayGetSize(pGroupbyExpr->columnInfo); ++i) {
+        SColumn* pCol = taosArrayGet(pGroupbyExpr->columnInfo, i);
+        len1 = sprintf(buf + len, "[%s #%d] ", pCol->name, pCol->info.colId);
+        len += len1;
+      }
+
+      len += sprintf(buf + len, "\n");
+      break;
+    }
+
+    case QNODE_FILL: {
+      SFillEssInfo* pEssInfo = pQueryNode->pExtInfo;
+      len1 = sprintf(buf + len, "%d", pEssInfo->fillType);
+      len += len1;
+
+      if (pEssInfo->fillType == TSDB_FILL_SET_VALUE) {
+        len1 = sprintf(buf + len, ", val:");
+        len += len1;
+
+        // todo get the correct fill data type
+        for (int32_t i = 0; i < pQueryNode->numOfExpr; ++i) {
+          len1 = sprintf(buf + len, "%" PRId64, pEssInfo->val[i]);
+          len += len1;
+
+          if (i < pQueryNode->numOfExpr - 1) {
+            len1 = sprintf(buf + len, ", ");
+            len += len1;
+          }
+        }
+      }
+
+      len1 = sprintf(buf + len, ")\n");
+      len += len1;
+      break;
+    }
+
+    case QNODE_LIMIT: {
+      SLimit* pVal = pQueryNode->pExtInfo;
+      len1 = sprintf(buf + len, "limit: %" PRId64 ", offset: %" PRId64 ")\n", pVal->limit, pVal->offset);
+      len += len1;
+      break;
+    }
+
+    case QNODE_DISTINCT:
+    case QNODE_TAGSCAN: {
+      len1 = sprintf(buf + len, "cols: ");
+      len += len1;
+
+      len = printExprInfo(buf, pQueryNode, len);
+
+      len1 = sprintf(buf + len, ")\n");
+      len += len1;
+
+      break;
+    }
+
+    case QNODE_SORT: {
+      len1 = sprintf(buf + len, "cols:");
+      len += len1;
+
+      SArray* pSort = pQueryNode->pExtInfo;
+      for (int32_t i = 0; i < taosArrayGetSize(pSort); ++i) {
+        SOrder* p = taosArrayGet(pSort, i);
+        len1 = sprintf(buf + len, " [%s #%d %s]", p->col.name, p->col.info.colId, p->order == TSDB_ORDER_ASC? "ASC":"DESC");
+
+        len += len1;
+      }
+
+      len1 = sprintf(buf + len, ")\n");
+      len += len1;
+      break;
+    }
+
+    case QNODE_JOIN: {
+      //  print join condition
+      len1 = sprintf(buf + len, ")\n");
+      len += len1;
+      break;
+    }
+  }
+
+  return len;
+}
+
+int32_t printExprInfo(char* buf, const SQueryPlanNode* pQueryNode, int32_t len) {
+  int32_t len1 = 0;
+
+  for (int32_t i = 0; i < pQueryNode->numOfExpr; ++i) {
+    SExprInfo* pExprInfo = taosArrayGetP(pQueryNode->pExpr, i);
+
+    SSqlExpr* pExpr = &pExprInfo->base;
+    len1 = sprintf(buf + len, "%s [%s #%d]", pExpr->token, pExpr->resSchema.name, pExpr->resSchema.colId);
+    assert(len1 > 0);
+
+    len += len1;
+    if (i < pQueryNode->numOfExpr - 1) {
+      len1 = sprintf(buf + len, ", ");
+      len += len1;
+    }
+  }
+
+  return len;
+}
+
+int32_t queryPlanToStringImpl(char* buf, SQueryPlanNode* pQueryNode, int32_t level, int32_t totalLen) {
+  int32_t len = doPrintPlan(buf, pQueryNode, level, totalLen);
+
+  for(int32_t i = 0; i < taosArrayGetSize(pQueryNode->pChildren); ++i) {
+    SQueryPlanNode* p1 = taosArrayGetP(pQueryNode->pChildren, i);
+    int32_t len1 = queryPlanToStringImpl(buf, p1, level + 1, len);
+    len = len1;
+  }
+
+  return len;
+}
+
+int32_t queryPlanToString(struct SQueryPlanNode* pQueryNode, char** str) {
+  assert(pQueryNode);
+
+  *str = calloc(1, 4096);
+
+  int32_t len = sprintf(*str, "===== logic plan =====\n");
+  queryPlanToStringImpl(*str, pQueryNode, 0, len);
+
+  return TSDB_CODE_SUCCESS;
+}
+
+SQueryPlanNode* queryPlanFromString() {
+  return NULL;
+}
diff --git a/source/libs/planner/src/physicalPlan.c b/source/libs/planner/src/physicalPlan.c
index e7acb12bc0ac9441249eec5f553ca22f0338b2aa..277703f5c0b65618a122f566884394f976f62837 100644
--- a/source/libs/planner/src/physicalPlan.c
+++ b/source/libs/planner/src/physicalPlan.c
@@ -16,6 +16,9 @@
 #include "plannerInt.h"
 #include "parser.h"
 
+#define STORE_CURRENT_SUBPLAN(cxt) SSubplan* _ = cxt->pCurrentSubplan
+#define RECOVERY_CURRENT_SUBPLAN(cxt) cxt->pCurrentSubplan = _
+
 static const char* gOpName[] = {
   "Unknown",
 #define INCLUDE_AS_NAME
@@ -43,8 +46,56 @@ static SPhyNode* initPhyNode(SQueryPlanNode* pPlanNode, int32_t type, int32_t si
   toDataBlockSchema(pPlanNode, &(node->targetSchema));
 }
 
+static SPhyNode* initScanNode(SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable, int32_t type, int32_t size) {
+  SScanPhyNode* node = (SScanPhyNode*)initPhyNode(pPlanNode, type, size);
+  node->uid = pTable->pMeta->pTableMeta->uid;
+  node->tableType = pTable->pMeta->pTableMeta->tableType;
+  return (SPhyNode*)node;
+}
+
+static SPhyNode* createPseudoScanNode(SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable, int32_t op) {
+  return initScanNode(pPlanNode, pTable, op, sizeof(SScanPhyNode));
+}
+
 static SPhyNode* createTagScanNode(SQueryPlanNode* pPlanNode) {
-  return initPhyNode(pPlanNode, OP_TagScan, sizeof(STagScanPhyNode));
+  SQueryTableInfo* pTable = (SQueryTableInfo*)pPlanNode->pExtInfo;
+  return createPseudoScanNode(pPlanNode, pTable, OP_TagScan);
+}
+
+static uint8_t getScanFlag(SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable) {
+  // todo
+  return MASTER_SCAN;
+}
+
+static SPhyNode* createUserTableScanNode(SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable, int32_t op) {
+  STableScanPhyNode* node = (STableScanPhyNode*)initScanNode(pPlanNode, pTable, op, sizeof(STableScanPhyNode));
+  node->scanFlag = getScanFlag(pPlanNode, pTable);
+  node->window = pTable->window;
+  // todo tag cond
+  return (SPhyNode*)node;
+}
+
+static SPhyNode* createSingleTableScanNode(SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable) {
+  return createUserTableScanNode(pPlanNode, pTable, OP_TableScan);
+}
+
+static bool isSystemTable(SQueryTableInfo* pTable) {
+  // todo
+  return false;
+}
+
+static bool needSeqScan(SQueryPlanNode* pPlanNode) {
+  // todo
+  return false;
+}
+
+static SPhyNode* createMultiTableScanNode(SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable) {
+  if (isSystemTable(pTable)) {
+    return createPseudoScanNode(pPlanNode, pTable, OP_SystemTableScan);
+  } else if (needSeqScan(pPlanNode)) {
+    return createUserTableScanNode(pPlanNode, pTable, OP_TableSeqScan);
+  }
+  return createUserTableScanNode(pPlanNode, pTable, OP_DataBlocksOptScan);
 }
 
 static SSubplan* initSubplan(SPlanContext* pCxt, int32_t type) {
@@ -58,53 +109,61 @@ static SSubplan* initSubplan(SPlanContext* pCxt, int32_t type) {
     if (NULL == pCxt->pCurrentSubplan->pChildern) {
       pCxt->pCurrentSubplan->pChildern = taosArrayInit(TARRAY_MIN_SIZE, POINTER_BYTES);
     }
-    taosArrayPush(pCxt->pCurrentSubplan->pChildern, subplan);
+    taosArrayPush(pCxt->pCurrentSubplan->pChildern, &subplan);
     subplan->pParents = taosArrayInit(TARRAY_MIN_SIZE, POINTER_BYTES);
-    taosArrayPush(subplan->pParents, pCxt->pCurrentSubplan);
+    taosArrayPush(subplan->pParents, &pCxt->pCurrentSubplan);
+  }
+  SArray* currentLevel;
+  if (subplan->level >= taosArrayGetSize(pCxt->pDag->pSubplans)) {
+    currentLevel = taosArrayInit(TARRAY_MIN_SIZE, POINTER_BYTES);
+    taosArrayPush(pCxt->pDag->pSubplans, &currentLevel);
+  } else {
+    currentLevel = taosArrayGetP(pCxt->pDag->pSubplans, subplan->level);
   }
+  taosArrayPush(currentLevel, &subplan);
   pCxt->pCurrentSubplan = subplan;
   return subplan;
 }
 
-static uint8_t getScanFlag(SQueryPlanNode* pPlanNode) {
-  // todo
-  return MASTER_SCAN;
-}
-
-static SPhyNode* createTableScanNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable) {
-  STableScanPhyNode* node = (STableScanPhyNode*)initPhyNode(pPlanNode, OP_TableScan, sizeof(STableScanPhyNode));
-  node->scan.uid = pTable->pMeta->pTableMeta->uid;
-  node->scan.tableType = pTable->pMeta->pTableMeta->tableType;
-  node->scanFlag = getScanFlag(pPlanNode);
-  node->window = pTable->window;
-  // todo tag cond
-}
-
 static void vgroupToEpSet(const SVgroupMsg* vg, SEpSet* epSet) {
-  // todo
+  epSet->inUse = 0; // todo
+  epSet->numOfEps = vg->numOfEps;
+  for (int8_t i = 0; i < vg->numOfEps; ++i) {
+    epSet->port[i] = vg->epAddr[i].port;
+    strcpy(epSet->fqdn[i], vg->epAddr[i].fqdn);
+  }
+  return;
 }
 
-static void splitSubplanBySTable(SPlanContext* pCxt, SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable) {
+static uint64_t splitSubplanByTable(SPlanContext* pCxt, SQueryPlanNode* pPlanNode, SQueryTableInfo* pTable) {
   SVgroupsInfo* vgroupList = pTable->pMeta->vgroupList;
   for (int32_t i = 0; i < pTable->pMeta->vgroupList->numOfVgroups; ++i) {
+    STORE_CURRENT_SUBPLAN(pCxt);
     SSubplan* subplan = initSubplan(pCxt, QUERY_TYPE_SCAN);
     vgroupToEpSet(&(pTable->pMeta->vgroupList->vgroups[i]), &subplan->execEpSet);
-    subplan->pNode = createTableScanNode(pCxt, pPlanNode, pTable);
-    // todo reset pCxt->pCurrentSubplan
+    subplan->pNode = createMultiTableScanNode(pPlanNode, pTable);
+    RECOVERY_CURRENT_SUBPLAN(pCxt);
   }
+  return pCxt->nextId.templateId++;
 }
 
-static SPhyNode* createExchangeNode() {
+static SPhyNode* createExchangeNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode, uint64_t srcTemplateId) {
+  SExchangePhyNode* node = (SExchangePhyNode*)initPhyNode(pPlanNode, OP_Exchange, sizeof(SExchangePhyNode));
+  node->srcTemplateId = srcTemplateId;
+  return (SPhyNode*)node;
+}
 
+static bool needMultiNodeScan(SQueryTableInfo* pTable) {
+  // todo system table, for instance, user_tables
+  return (TSDB_SUPER_TABLE == pTable->pMeta->pTableMeta->tableType);
 }
 
-static SPhyNode* createScanNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode) {
+static SPhyNode* createTableScanNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode) {
   SQueryTableInfo* pTable = (SQueryTableInfo*)pPlanNode->pExtInfo;
-  if (TSDB_SUPER_TABLE == pTable->pMeta->pTableMeta->tableType) {
-    splitSubplanBySTable(pCxt, pPlanNode, pTable);
-    return createExchangeNode(pCxt, pTable);
+  if (needMultiNodeScan(pTable)) {
+    return createExchangeNode(pCxt, pPlanNode, splitSubplanByTable(pCxt, pPlanNode, pTable));
   }
-  return createTableScanNode(pCxt, pPlanNode, pTable);
+  return createSingleTableScanNode(pPlanNode, pTable);
 }
 
 static SPhyNode* createPhyNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode) {
@@ -114,7 +173,7 @@ static SPhyNode* createPhyNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode) {
       node = createTagScanNode(pPlanNode);
       break;
     case QNODE_TABLESCAN:
-      node = createScanNode(pCxt, pPlanNode);
+      node = createTableScanNode(pCxt, pPlanNode);
       break;
     default:
       assert(false);
@@ -133,6 +192,7 @@ static SPhyNode* createPhyNode(SPlanContext* pCxt, SQueryPlanNode* pPlanNode) {
 
 static void createSubplanByLevel(SPlanContext* pCxt, SQueryPlanNode* pRoot) {
   SSubplan* subplan = initSubplan(pCxt, QUERY_TYPE_MERGE);
+  ++(pCxt->nextId.templateId);
   subplan->pNode = createPhyNode(pCxt, pRoot);
   SArray* l0 = taosArrayInit(TARRAY_MIN_SIZE, POINTER_BYTES);
   taosArrayPush(l0, &subplan);
@@ -144,7 +204,8 @@ int32_t createDag(SQueryPlanNode* pQueryNode, struct SCatalog* pCatalog, SQueryD
   SPlanContext context = {
     .pCatalog = pCatalog,
     .pDag = calloc(1, sizeof(SQueryDag)),
-    .pCurrentSubplan = NULL
+    .pCurrentSubplan = NULL,
+    .nextId = {0} // todo queryid
   };
   if (NULL == context.pDag) {
     return TSDB_CODE_TSC_OUT_OF_MEMORY;
diff --git a/source/libs/planner/src/planner.c b/source/libs/planner/src/planner.c
index 19aac36e780dd2308fedd8907cc861f1e84be1d6..744a849e2d55e1293f35f2707acb000e3a8f4221 100644
--- a/source/libs/planner/src/planner.c
+++ b/source/libs/planner/src/planner.c
@@ -13,606 +13,31 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include "function.h"
-#include "os.h"
 #include "parser.h"
 #include "plannerInt.h"
 
-typedef struct SFillEssInfo {
-  int32_t  fillType;  // fill type
-  int64_t *val;       // fill value
-} SFillEssInfo;
-
-typedef struct SJoinCond {
-  bool     tagExists; // denote if tag condition exists or not
-  SColumn *tagCond[2];
-  SColumn *colCond[2];
-} SJoinCond;
-
-static SArray* createQueryPlanImpl(SQueryStmtInfo* pQueryInfo);
-static void doDestroyQueryNode(SQueryPlanNode* pQueryNode);
-
-int32_t printExprInfo(const char* buf, const SQueryPlanNode* pQueryNode, int32_t len);
-int32_t optimizeQueryPlan(struct SQueryPlanNode* pQueryNode) {
-  return 0;
-}
-
-int32_t createQueryPlan(const struct SQueryStmtInfo* pQueryInfo, struct SQueryPlanNode** pQueryNode) {
-  SArray* upstream = createQueryPlanImpl((struct SQueryStmtInfo*) pQueryInfo);
-  assert(taosArrayGetSize(upstream) == 1);
-
-  *pQueryNode = taosArrayGetP(upstream, 0);
-
-  taosArrayDestroy(upstream);
-  return TSDB_CODE_SUCCESS;
-}
-
-int32_t queryPlanToSql(struct SQueryPlanNode* pQueryNode, char** sql) {
-  return 0;
-}
-
-int32_t qCreatePhysicalPlan(struct SQueryPlanNode* pQueryNode, struct SEpSet* pQnode, struct SQueryDag** pDag) {
-
-  return 0;
-}
-
-int32_t phyPlanToString(struct SPhyNode *pPhyNode, char** str) {
-  return 0;
-}
-
-void* destroyQueryPlan(SQueryPlanNode* pQueryNode) {
-  if (pQueryNode == NULL) {
-    return NULL;
-  }
-
-  doDestroyQueryNode(pQueryNode);
-  return NULL;
-}
-
-void* destroyQueryPhyPlan(struct SPhyNode* pQueryPhyNode) {
-  return NULL;
-}
-
-//======================================================================================================================
-
-static SQueryPlanNode* createQueryNode(int32_t type, const char* name, SQueryPlanNode** prev, int32_t numOfPrev,
-                                   SExprInfo** pExpr, int32_t numOfOutput, void* pExtInfo) {
-  SQueryPlanNode* pNode = calloc(1, sizeof(SQueryPlanNode));
-
-  pNode->info.type = type;
-  pNode->info.name = strdup(name);
-
-  pNode->numOfExpr = numOfOutput;
-  pNode->pExpr = taosArrayInit(numOfOutput, POINTER_BYTES);
-
-  for(int32_t i = 0; i < numOfOutput; ++i) {
-    taosArrayPush(pNode->pExpr, &pExpr[i]);
-  }
-
-  pNode->pChildren = taosArrayInit(4, POINTER_BYTES);
-  for(int32_t i = 0; i < numOfPrev; ++i) {
-    taosArrayPush(pNode->pChildren, &prev[i]);
-  }
-
-  switch(type) {
-    case QNODE_TAGSCAN:
-    case QNODE_TABLESCAN: {
-      SQueryTableInfo* info = calloc(1, sizeof(SQueryTableInfo));
-      memcpy(info, pExtInfo, sizeof(SQueryTableInfo));
-      info->tableName = strdup(((SQueryTableInfo*) pExtInfo)->tableName);
-      pNode->pExtInfo = info;
-      break;
-    }
-
-    case QNODE_TIMEWINDOW: {
-      SInterval* pInterval = calloc(1, sizeof(SInterval));
-      pNode->pExtInfo = pInterval;
-      memcpy(pInterval, pExtInfo, sizeof(SInterval));
-      break;
-    }
-
-    case QNODE_STATEWINDOW: {
-      SColumn* psw = calloc(1, sizeof(SColumn));
-      pNode->pExtInfo = psw;
-      memcpy(psw, pExtInfo, sizeof(SColumn));
-      break;
-    }
-
-    case QNODE_SESSIONWINDOW: {
-      SSessionWindow *pSessionWindow = calloc(1, sizeof(SSessionWindow));
-      pNode->pExtInfo = pSessionWindow;
-      memcpy(pSessionWindow, pExtInfo, sizeof(struct SSessionWindow));
-      break;
-    }
-
-    case QNODE_GROUPBY: {
-      SGroupbyExpr* p = (SGroupbyExpr*) pExtInfo;
-
-      SGroupbyExpr* pGroupbyExpr = calloc(1, sizeof(SGroupbyExpr));
-      pGroupbyExpr->groupbyTag = p->groupbyTag;
-      pGroupbyExpr->columnInfo = taosArrayDup(p->columnInfo);
-
-      pNode->pExtInfo = pGroupbyExpr;
-      break;
-    }
-
-    case QNODE_FILL: { // todo !!
-      pNode->pExtInfo = pExtInfo;
-      break;
-    }
-
-    case QNODE_LIMIT: {
-      pNode->pExtInfo = calloc(1, sizeof(SLimit));
-      memcpy(pNode->pExtInfo, pExtInfo, sizeof(SLimit));
-      break;
-    }
-
-    case QNODE_SORT: {
-      pNode->pExtInfo = taosArrayDup(pExtInfo);
-      break;
-    }
-
-    default:
-      break;
-  }
-  
-  return pNode;
-}
-
-static SQueryPlanNode* doAddTableColumnNode(SQueryStmtInfo* pQueryInfo, STableMetaInfo* pTableMetaInfo, SQueryTableInfo* info,
-                                        SArray* pExprs, SArray* tableCols) {
-  if (pQueryInfo->info.onlyTagQuery) {
-    int32_t num = (int32_t) taosArrayGetSize(pExprs);
-    SQueryPlanNode* pNode = createQueryNode(QNODE_TAGSCAN, "TableTagScan", NULL, 0, pExprs->pData, num, info);
-
-    if (pQueryInfo->info.distinct) {
-      pNode = createQueryNode(QNODE_DISTINCT, "Distinct", &pNode, 1, pExprs->pData, num, NULL);
-    }
-
-    return pNode;
-  }
-
-  SQueryPlanNode*  pNode = createQueryNode(QNODE_TABLESCAN, "TableScan", NULL, 0, NULL, 0, info);
-
-  if (pQueryInfo->info.projectionQuery) {
-    int32_t numOfOutput = (int32_t) taosArrayGetSize(pExprs);
-    pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, pExprs->pData, numOfOutput, NULL);
-  } else {
-    STableMetaInfo* pTableMetaInfo1 = getMetaInfo(pQueryInfo, 0);
-
-    // table source column projection, generate the projection expr
-    int32_t     numOfCols = (int32_t) taosArrayGetSize(tableCols);
-    SExprInfo** pExpr = calloc(numOfCols, POINTER_BYTES);
-    for (int32_t i = 0; i < numOfCols; ++i) {
-      SColumn* pCol = taosArrayGetP(tableCols, i);
-
-      SSourceParam param = {0};
-      addIntoSourceParam(&param, NULL, pCol);
-      SSchema s = createSchema(pCol->info.type, pCol->info.bytes, pCol->info.colId, pCol->name);
-      SExprInfo* p = createExprInfo(pTableMetaInfo1, "project", &param, &s, 0);
-      pExpr[i] = p;
-    }
-
-    pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, pExpr, numOfCols, NULL);
-    tfree(pExpr);
-  }
-
-  return pNode;
-}
-
-static SQueryPlanNode* doCreateQueryPlanForSingleTableImpl(SQueryStmtInfo* pQueryInfo, SQueryPlanNode* pNode, SQueryTableInfo* info) {
-  // group by column not by tag
-  size_t numOfGroupCols = taosArrayGetSize(pQueryInfo->groupbyExpr.columnInfo);
-
-  // check for aggregation
-  int32_t level = getExprFunctionLevel(pQueryInfo);
-
-  for(int32_t i = level - 1; i >= 0; --i) {
-    SArray* p = pQueryInfo->exprList[i];
-    size_t  num = taosArrayGetSize(p);
-
-    bool aggregateFunc = false;
-    for(int32_t j = 0; j < num; ++j) {
-      SExprInfo* pExpr = (SExprInfo*)taosArrayGetP(p, 0);
-      if (pExpr->pExpr->nodeType != TEXPR_FUNCTION_NODE) {
-        continue;
-      }
-
-      aggregateFunc = qIsAggregateFunction(pExpr->pExpr->_function.functionName);
-      if (aggregateFunc) {
-        break;
-      }
-    }
-
-    if (aggregateFunc) {
-      if (pQueryInfo->interval.interval > 0) {
-        pNode = createQueryNode(QNODE_TIMEWINDOW, "TimeWindowAgg", &pNode, 1, p->pData, num, &pQueryInfo->interval);
-      } else if (pQueryInfo->sessionWindow.gap > 0) {
-        pNode = createQueryNode(QNODE_SESSIONWINDOW, "SessionWindowAgg", &pNode, 1, p->pData, num, &pQueryInfo->sessionWindow);
-      } else if (pQueryInfo->stateWindow.col.info.colId > 0) {
-        pNode = createQueryNode(QNODE_STATEWINDOW, "StateWindowAgg", &pNode, 1, p->pData, num, &pQueryInfo->stateWindow);
-      } else if (numOfGroupCols != 0 && !pQueryInfo->groupbyExpr.groupbyTag) {
-          pNode = createQueryNode(QNODE_GROUPBY, "Groupby", &pNode, 1, p->pData, num, &pQueryInfo->groupbyExpr);
-      } else {
-        pNode = createQueryNode(QNODE_AGGREGATE, "Aggregate", &pNode, 1, p->pData, num, NULL);
-      }
-    } else {
-      pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, p->pData, num, NULL);
-    }
-  }
-
-  if (pQueryInfo->havingFieldNum > 0) {
-//    int32_t numOfExpr = (int32_t)taosArrayGetSize(pQueryInfo->exprList1);
-//    pNode = createQueryNode(QNODE_PROJECT, "Projection", &pNode, 1, pQueryInfo->exprList1->pData, numOfExpr, NULL);
-  }
-
-  if (pQueryInfo->fillType != TSDB_FILL_NONE) {
-    SFillEssInfo* pInfo = calloc(1, sizeof(SFillEssInfo));
-    pInfo->fillType = pQueryInfo->fillType;
-    pInfo->val      = calloc(pNode->numOfExpr, sizeof(int64_t));
-    memcpy(pInfo->val, pQueryInfo->fillVal, pNode->numOfExpr);
-
-    SArray* p = pQueryInfo->exprList[0];  // top expression in select clause
-    pNode = createQueryNode(QNODE_FILL, "Fill", &pNode, 1, p, taosArrayGetSize(p), pInfo);
-  }
-
-  if (pQueryInfo->order != NULL) {
-    SArray* pList = pQueryInfo->exprList[0];
-    pNode = createQueryNode(QNODE_SORT, "Sort", &pNode, 1, pList->pData, taosArrayGetSize(pList), pQueryInfo->order);
-  }
-
-  if (pQueryInfo->limit.limit != -1 || pQueryInfo->limit.offset != 0) {
-    pNode = createQueryNode(QNODE_LIMIT, "Limit", &pNode, 1, NULL, 0, &pQueryInfo->limit);
-  }
-
-  return pNode;
-}
-
-static SQueryPlanNode* doCreateQueryPlanForSingleTable(SQueryStmtInfo* pQueryInfo, STableMetaInfo* pTableMetaInfo, SArray* pExprs,
-                                                SArray* tableCols) {
-  char name[TSDB_TABLE_FNAME_LEN] = {0};
-  tstrncpy(name, pTableMetaInfo->name.tname, TSDB_TABLE_FNAME_LEN);
-
-  SQueryTableInfo info = {.tableName = strdup(name), .uid = pTableMetaInfo->pTableMeta->uid,};
-
-  // handle the only tag query
-  SQueryPlanNode* pNode = doAddTableColumnNode(pQueryInfo, pTableMetaInfo, &info, pExprs, tableCols);
-  if (pQueryInfo->info.onlyTagQuery) {
-    tfree(info.tableName);
-    return pNode;
-  }
-
-  SQueryPlanNode* pNode1 = doCreateQueryPlanForSingleTableImpl(pQueryInfo, pNode, &info);
-  tfree(info.tableName);
-  return pNode1;
-}
-
-static bool isAllAggExpr(SArray* pList) {
-  assert(pList != NULL);
-
-  for (int32_t k = 0; k < taosArrayGetSize(pList); ++k) {
-    SExprInfo* p = taosArrayGetP(pList, k);
-    if (p->pExpr->nodeType != TEXPR_FUNCTION_NODE || !qIsAggregateFunction(p->pExpr->_function.functionName)) {
-      return false;
-    }
-  }
-
-  return true;
+void qDestroyQueryDag(struct SQueryDag* pDag) {
+  // todo
 }
 
-SArray* createQueryPlanImpl(SQueryStmtInfo* pQueryInfo) {
-  SArray* upstream = NULL;
-
-  if (pQueryInfo->pUpstream != NULL && taosArrayGetSize(pQueryInfo->pUpstream) > 0) {  // subquery in the from clause
-    upstream = taosArrayInit(4, POINTER_BYTES);
-
-    size_t size = taosArrayGetSize(pQueryInfo->pUpstream);
-    for(int32_t i = 0; i < size; ++i) {
-      SQueryStmtInfo* pq = taosArrayGet(pQueryInfo->pUpstream, i);
-      SArray* p = createQueryPlanImpl(pq);
-      taosArrayAddBatch(upstream, p->pData, (int32_t) taosArrayGetSize(p));
-    }
+int32_t qCreateQueryDag(const struct SQueryStmtInfo* pQueryInfo, struct SEpSet* pQnode, struct SQueryDag** pDag) {
+  SQueryPlanNode* logicPlan;
+  int32_t code = createQueryPlan(pQueryInfo, &logicPlan);
+  if (TSDB_CODE_SUCCESS != code) {
+    destroyQueryPlan(logicPlan);
+    return code;
   }
-
-  if (pQueryInfo->numOfTables > 1) {  // it is a join query
-    // 1. separate the select clause according to table
-    taosArrayDestroy(upstream);
-    upstream = taosArrayInit(5, POINTER_BYTES);
-
-    for(int32_t i = 0; i < pQueryInfo->numOfTables; ++i) {
-      STableMetaInfo* pTableMetaInfo = pQueryInfo->pTableMetaInfo[i];
-      uint64_t        uid = pTableMetaInfo->pTableMeta->uid;
-
-      SArray* exprList = taosArrayInit(4, POINTER_BYTES);
-      if (copyExprInfoList(exprList, pQueryInfo->exprList[0], uid, true) != 0) {
-        terrno = TSDB_CODE_TSC_OUT_OF_MEMORY;
-//        dropAllExprInfo(exprList);
-        exit(-1);
-      }
-
-      // 2. create the query execution node
-      char name[TSDB_TABLE_FNAME_LEN] = {0};
-      tNameExtractFullName(&pTableMetaInfo->name, name);
-      SQueryTableInfo info = {.tableName = strdup(name), .uid = pTableMetaInfo->pTableMeta->uid,};
-
-      // 3. get the required table column list
-      SArray* tableColumnList = taosArrayInit(4, sizeof(SColumn));
-      columnListCopy(tableColumnList, pQueryInfo->colList, uid);
-
-      // 4. add the projection query node
-      SQueryPlanNode* pNode = doAddTableColumnNode(pQueryInfo, pTableMetaInfo, &info, exprList, tableColumnList);
-      columnListDestroy(tableColumnList);
-//      dropAllExprInfo(exprList);
-      taosArrayPush(upstream, &pNode);
-    }
-
-    // 3. add the join node here
-    SQueryTableInfo info = {0};
-    int32_t num = (int32_t) taosArrayGetSize(pQueryInfo->exprList[0]);
-    SQueryPlanNode* pNode = createQueryNode(QNODE_JOIN, "Join", upstream->pData, pQueryInfo->numOfTables,
-                                        pQueryInfo->exprList[0]->pData, num, NULL);
-
-    // 4. add the aggregation or projection execution node
-    pNode = doCreateQueryPlanForSingleTableImpl(pQueryInfo, pNode, &info);
-    upstream = taosArrayInit(5, POINTER_BYTES);
-    taosArrayPush(upstream, &pNode);
-  } else { // only one table, normal query process
-    STableMetaInfo* pTableMetaInfo = pQueryInfo->pTableMetaInfo[0];
-    SQueryPlanNode* pNode = doCreateQueryPlanForSingleTable(pQueryInfo, pTableMetaInfo, pQueryInfo->exprList[0], pQueryInfo->colList);
-    upstream = taosArrayInit(5, POINTER_BYTES);
-    taosArrayPush(upstream, &pNode);
-  }
-
-  return upstream;
-}
-
-static void doDestroyQueryNode(SQueryPlanNode* pQueryNode) {
-  tfree(pQueryNode->pExtInfo);
-  tfree(pQueryNode->pSchema);
-  tfree(pQueryNode->info.name);
-//  dropAllExprInfo(pQueryNode->pExpr);
-
-  if (pQueryNode->pChildren != NULL) {
-    int32_t size = (int32_t) taosArrayGetSize(pQueryNode->pChildren);
-    for(int32_t i = 0; i < size; ++i) {
-      SQueryPlanNode* p = taosArrayGetP(pQueryNode->pChildren, i);
-      doDestroyQueryNode(p);
-    }
-
-    taosArrayDestroy(pQueryNode->pChildren);
+  code = optimizeQueryPlan(logicPlan);
+  if (TSDB_CODE_SUCCESS != code) {
+    destroyQueryPlan(logicPlan);
+    return code;
   }
-
-  tfree(pQueryNode);
-}
-
-static int32_t doPrintPlan(char* buf, SQueryPlanNode* pQueryNode, int32_t level, int32_t totalLen) {
-  if (level > 0) {
-    sprintf(buf + totalLen, "%*c", level, ' ');
-    totalLen += level;
+  code = createDag(logicPlan, NULL, pDag);
+  if (TSDB_CODE_SUCCESS != code) {
+    destroyQueryPlan(logicPlan);
+    qDestroyQueryDag(*pDag);
+    return code;
   }
-
-  int32_t len1 = sprintf(buf + totalLen, "%s(", pQueryNode->info.name);
-  int32_t len = len1 + totalLen;
-
-  switch(pQueryNode->info.type) {
-    case QNODE_TABLESCAN: {
-      SQueryTableInfo* pInfo = (SQueryTableInfo*)pQueryNode->pExtInfo;
-      len1 = sprintf(buf + len, "%s #%" PRIu64 ") time_range: %" PRId64 " - %" PRId64, pInfo->tableName, pInfo->uid,
-                     pInfo->window.skey, pInfo->window.ekey);
-      assert(len1 > 0);
-      len += len1;
-
-      for (int32_t i = 0; i < pQueryNode->numOfExpr; ++i) {
-        SColumn* pCol = taosArrayGetP(pQueryNode->pExpr, i);
-        len1 = sprintf(buf + len, " [%s #%d] ", pCol->name, pCol->info.colId);
-
-        assert(len1 > 0);
-        len += len1;
-      }
-
-      len1 = sprintf(buf + len, "\n");
-      assert(len1 > 0);
-
-      len += len1;
-      break;
-    }
-
-    case QNODE_PROJECT: {
-      len1 = sprintf(buf + len, "cols:");
-      assert(len1 > 0);
-      len += len1;
-
-      len = printExprInfo(buf, pQueryNode, len);
-      len1 = sprintf(buf + len, ")");
-      len += len1;
-
-      // todo print filter info
-      len1 = sprintf(buf + len, " filters:(nil)\n");
-      len += len1;
-      break;
-    }
-
-    case QNODE_AGGREGATE: {
-      len = printExprInfo(buf, pQueryNode, len);
-      len1 = sprintf(buf + len, ")\n");
-      len += len1;
-
-      break;
-    }
-
-    case QNODE_TIMEWINDOW: {
-      len = printExprInfo(buf, pQueryNode, len);
-      len1 = sprintf(buf + len, ") ");
-      len += len1;
-
-      SInterval* pInterval = pQueryNode->pExtInfo;
-
-      // todo dynamic return the time precision
-      len1 = sprintf(buf + len, "interval:%" PRId64 "(%s), sliding:%" PRId64 "(%s), offset:%" PRId64 "(%s)\n",
-                     pInterval->interval, TSDB_TIME_PRECISION_MILLI_STR, pInterval->sliding,
-                     TSDB_TIME_PRECISION_MILLI_STR, pInterval->offset, TSDB_TIME_PRECISION_MILLI_STR);
-      len += len1;
-
-      break;
-    }
-
-    case QNODE_STATEWINDOW: {
-      len = printExprInfo(buf, pQueryNode, len);
-      len1 = sprintf(buf + len, ") ");
-      len += len1;
-
-      SColumn* pCol = pQueryNode->pExtInfo;
-      len1 = sprintf(buf + len, "col:%s #%d\n", pCol->name, pCol->info.colId);
-      len += len1;
-      break;
-    }
-
-    case QNODE_SESSIONWINDOW: {
-      len = printExprInfo(buf, pQueryNode, len);
-
-      len1 = sprintf(buf + len, ") ");
-      len += len1;
-
-      struct SSessionWindow* ps = pQueryNode->pExtInfo;
-      len1 = sprintf(buf + len, "col:[%s #%d], gap:%" PRId64 " (ms) \n", ps->col.name, ps->col.info.colId, ps->gap);
-      len += len1;
-      break;
-    }
-
-    case QNODE_GROUPBY: {
-      len = printExprInfo(buf, pQueryNode, len);
-
-      SGroupbyExpr* pGroupbyExpr = pQueryNode->pExtInfo;
-      len1 = sprintf(buf + len, ") groupby_col: ");
-      len += len1;
-
-      for (int32_t i = 0; i < taosArrayGetSize(pGroupbyExpr->columnInfo); ++i) {
-        SColumn* pCol = taosArrayGet(pGroupbyExpr->columnInfo, i);
-        len1 = sprintf(buf + len, "[%s #%d] ", pCol->name, pCol->info.colId);
-        len += len1;
-      }
-
-      len += sprintf(buf + len, "\n");
-      break;
-    }
-
-    case QNODE_FILL: {
-      SFillEssInfo* pEssInfo = pQueryNode->pExtInfo;
-      len1 = sprintf(buf + len, "%d", pEssInfo->fillType);
-      len += len1;
-
-      if (pEssInfo->fillType == TSDB_FILL_SET_VALUE) {
-        len1 = sprintf(buf + len, ", val:");
-        len += len1;
-
-        // todo get the correct fill data type
-        for (int32_t i = 0; i < pQueryNode->numOfExpr; ++i) {
-          len1 = sprintf(buf + len, "%" PRId64, pEssInfo->val[i]);
-          len += len1;
-
-          if (i < pQueryNode->numOfExpr - 1) {
-            len1 = sprintf(buf + len, ", ");
-            len += len1;
-          }
-        }
-      }
-
-      len1 = sprintf(buf + len, ")\n");
-      len += len1;
-      break;
-    }
-
-    case QNODE_LIMIT: {
-      SLimit* pVal = pQueryNode->pExtInfo;
-      len1 = sprintf(buf + len, "limit: %" PRId64 ", offset: %" PRId64 ")\n", pVal->limit, pVal->offset);
-      len += len1;
-      break;
-    }
-
-    case QNODE_DISTINCT:
-    case QNODE_TAGSCAN: {
-      len1 = sprintf(buf + len, "cols: ");
-      len += len1;
-
-      len = printExprInfo(buf, pQueryNode, len);
-
-      len1 = sprintf(buf + len, ")\n");
-      len += len1;
-
-      break;
-    }
-
-    case QNODE_SORT: {
-      len1 = sprintf(buf + len, "cols:");
-      len += len1;
-
-      SArray* pSort = pQueryNode->pExtInfo;
-      for (int32_t i = 0; i < taosArrayGetSize(pSort); ++i) {
-        SOrder* p = taosArrayGet(pSort, i);
-        len1 = sprintf(buf + len, " [%s #%d %s]", p->col.name, p->col.info.colId, p->order == TSDB_ORDER_ASC? "ASC":"DESC");
-
-        len += len1;
-      }
-
-      len1 = sprintf(buf + len, ")\n");
-      len += len1;
-      break;
-    }
-
-    case QNODE_JOIN: {
-      //  print join condition
-      len1 = sprintf(buf + len, ")\n");
-      len += len1;
-      break;
-    }
-  }
-
-  return len;
-}
-
-int32_t printExprInfo(const char* buf, const SQueryPlanNode* pQueryNode, int32_t len) {
-  int32_t len1 = 0;
-
-  for (int32_t i = 0; i < pQueryNode->numOfExpr; ++i) {
-    SExprInfo* pExprInfo = taosArrayGetP(pQueryNode->pExpr, i);
-
-    SSqlExpr* pExpr = &pExprInfo->base;
-    len1 = sprintf(buf + len, "%s [%s #%d]", pExpr->token, pExpr->resSchema.name, pExpr->resSchema.colId);
-    assert(len1 > 0);
-
-    len += len1;
-    if (i < pQueryNode->numOfExpr - 1) {
-      len1 = sprintf(buf + len, ", ");
-      len += len1;
-    }
-  }
-
-  return len;
-}
-
-int32_t queryPlanToStringImpl(char* buf, SQueryPlanNode* pQueryNode, int32_t level, int32_t totalLen) {
-  int32_t len = doPrintPlan(buf, pQueryNode, level, totalLen);
-
-  for(int32_t i = 0; i < taosArrayGetSize(pQueryNode->pChildren); ++i) {
-    SQueryPlanNode* p1 = taosArrayGetP(pQueryNode->pChildren, i);
-    int32_t len1 = queryPlanToStringImpl(buf, p1, level + 1, len);
-    len = len1;
-  }
-
-  return len;
-}
-
-int32_t queryPlanToString(struct SQueryPlanNode* pQueryNode, char** str) {
-  assert(pQueryNode);
-
-  *str = calloc(1, 4096);
-
-  int32_t len = sprintf(*str, "===== logic plan =====\n");
-  queryPlanToStringImpl(*str, pQueryNode, 0, len);
-
+  destroyQueryPlan(logicPlan);
   return TSDB_CODE_SUCCESS;
 }
-
-SQueryPlanNode* queryPlanFromString() {
-  return NULL;
-}