homework-jianmu/source/libs/parser/src/parCalcConst.c

513 lines
15 KiB
C

/*
* 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 "functionMgt.h"
#include "parInt.h"
#include "scalar.h"
#include "ttime.h"
typedef struct SCalcConstContext {
SParseContext* pParseCxt;
SMsgBuf msgBuf;
int32_t code;
} SCalcConstContext;
static int32_t calcConstQuery(SCalcConstContext* pCxt, SNode* pStmt, bool subquery);
static int32_t calcConstSubquery(SCalcConstContext* pCxt, STempTableNode* pTempTable) {
return calcConstQuery(pCxt, pTempTable->pSubquery, true);
}
static int32_t calcConstNode(SNode** pNode) {
if (NULL == *pNode) {
return TSDB_CODE_SUCCESS;
}
SNode* pNew = NULL;
int32_t code = scalarCalculateConstants(*pNode, &pNew);
if (TSDB_CODE_SUCCESS == code) {
*pNode = pNew;
}
return code;
}
static int32_t calcConstList(SNodeList* pList) {
SNode* pNode = NULL;
FOREACH(pNode, pList) {
SNode* pNew = NULL;
int32_t code = scalarCalculateConstants(pNode, &pNew);
if (TSDB_CODE_SUCCESS == code) {
REPLACE_NODE(pNew);
} else {
return code;
}
}
return TSDB_CODE_SUCCESS;
}
static bool isCondition(const SNode* pNode) {
if (QUERY_NODE_OPERATOR == nodeType(pNode)) {
return nodesIsComparisonOp((const SOperatorNode*)pNode);
}
return (QUERY_NODE_LOGIC_CONDITION == nodeType(pNode));
}
static int32_t rewriteIsTrue(SNode* pSrc, SNode** pIsTrue) {
SOperatorNode* pOp = (SOperatorNode*)nodesMakeNode(QUERY_NODE_OPERATOR);
if (NULL == pOp) {
return TSDB_CODE_OUT_OF_MEMORY;
}
pOp->opType = OP_TYPE_IS_TRUE;
pOp->pLeft = pSrc;
pOp->node.resType.type = TSDB_DATA_TYPE_BOOL;
pOp->node.resType.bytes = tDataTypes[TSDB_DATA_TYPE_BOOL].bytes;
*pIsTrue = (SNode*)pOp;
return TSDB_CODE_SUCCESS;
}
static EDealRes doRewriteCondition(SNode** pNode, void* pContext) {
if (QUERY_NODE_LOGIC_CONDITION == nodeType(*pNode)) {
SNode* pParam = NULL;
FOREACH(pParam, ((SLogicConditionNode*)*pNode)->pParameterList) {
if (!isCondition(pParam)) {
SNode* pIsTrue = NULL;
if (TSDB_CODE_SUCCESS != rewriteIsTrue(pParam, &pIsTrue)) {
((SCalcConstContext*)pContext)->code = TSDB_CODE_OUT_OF_MEMORY;
return DEAL_RES_ERROR;
}
REPLACE_NODE(pIsTrue);
}
}
}
return DEAL_RES_CONTINUE;
}
static int32_t rewriteCondition(SCalcConstContext* pCxt, SNode** pNode) {
if (!isCondition(*pNode)) {
return rewriteIsTrue(*pNode, pNode);
}
nodesRewriteExprPostOrder(pNode, doRewriteCondition, pCxt);
return pCxt->code;
}
static int32_t calcConstCondition(SCalcConstContext* pCxt, SNode** pNode) {
int32_t code = rewriteCondition(pCxt, pNode);
if (TSDB_CODE_SUCCESS == code) {
code = calcConstNode(pNode);
}
return code;
}
static int32_t rewriteConditionForFromTable(SCalcConstContext* pCxt, SNode* pTable) {
int32_t code = TSDB_CODE_SUCCESS;
switch (nodeType(pTable)) {
case QUERY_NODE_TEMP_TABLE: {
code = calcConstSubquery(pCxt, (STempTableNode*)pTable);
break;
}
case QUERY_NODE_JOIN_TABLE: {
SJoinTableNode* pJoin = (SJoinTableNode*)pTable;
code = rewriteConditionForFromTable(pCxt, pJoin->pLeft);
if (TSDB_CODE_SUCCESS == code) {
code = rewriteConditionForFromTable(pCxt, pJoin->pRight);
}
if (TSDB_CODE_SUCCESS == code && NULL != pJoin->pOnCond) {
code = calcConstCondition(pCxt, &pJoin->pOnCond);
}
// todo empty table
break;
}
default:
break;
}
return code;
}
static int32_t calcConstFromTable(SCalcConstContext* pCxt, SNode* pTable) {
return rewriteConditionForFromTable(pCxt, pTable);
}
static void rewriteConstCondition(SNode** pCond, bool* pAlwaysFalse) {
if (QUERY_NODE_VALUE != nodeType(*pCond)) {
return;
}
if (((SValueNode*)*pCond)->datum.b) {
nodesDestroyNode(*pCond);
*pCond = NULL;
} else {
*pAlwaysFalse = true;
}
}
static int32_t calcConstStmtCondition(SCalcConstContext* pCxt, SNode** pCond, bool* pAlwaysFalse) {
if (NULL == *pCond) {
return TSDB_CODE_SUCCESS;
}
int32_t code = rewriteCondition(pCxt, pCond);
if (TSDB_CODE_SUCCESS == code) {
code = calcConstNode(pCond);
}
if (TSDB_CODE_SUCCESS == code) {
rewriteConstCondition(pCond, pAlwaysFalse);
}
return code;
}
static int32_t calcConstProject(SNode* pProject, bool dual, SNode** pNew) {
SArray* pAssociation = NULL;
if (NULL != ((SExprNode*)pProject)->pAssociation) {
pAssociation = taosArrayDup(((SExprNode*)pProject)->pAssociation, NULL);
if (NULL == pAssociation) {
return TSDB_CODE_OUT_OF_MEMORY;
}
}
char aliasName[TSDB_COL_NAME_LEN] = {0};
strcpy(aliasName, ((SExprNode*)pProject)->aliasName);
int32_t code = TSDB_CODE_SUCCESS;
if (dual) {
code = scalarCalculateConstantsFromDual(pProject, pNew);
} else {
code = scalarCalculateConstants(pProject, pNew);
}
if (TSDB_CODE_SUCCESS == code) {
strcpy(((SExprNode*)*pNew)->aliasName, aliasName);
if (QUERY_NODE_VALUE == nodeType(*pNew) && NULL != pAssociation) {
int32_t size = taosArrayGetSize(pAssociation);
for (int32_t i = 0; i < size; ++i) {
SNode** pCol = taosArrayGetP(pAssociation, i);
nodesDestroyNode(*pCol);
*pCol = nodesCloneNode(*pNew);
if (NULL == *pCol) {
code = TSDB_CODE_OUT_OF_MEMORY;
break;
}
}
}
}
taosArrayDestroy(pAssociation);
return code;
}
static bool isUselessCol(SExprNode* pProj) {
if (QUERY_NODE_FUNCTION == nodeType(pProj) && !fmIsScalarFunc(((SFunctionNode*)pProj)->funcId) &&
!fmIsPseudoColumnFunc(((SFunctionNode*)pProj)->funcId)) {
return false;
}
return NULL == ((SExprNode*)pProj)->pAssociation;
}
static SNode* createConstantValue() {
SValueNode* pVal = (SValueNode*)nodesMakeNode(QUERY_NODE_VALUE);
if (NULL == pVal) {
return NULL;
}
pVal->node.resType.type = TSDB_DATA_TYPE_INT;
pVal->node.resType.bytes = tDataTypes[TSDB_DATA_TYPE_INT].bytes;
const int32_t val = 1;
nodesSetValueNodeValue(pVal, (void*)&val);
pVal->translate = true;
return (SNode*)pVal;
}
static int32_t calcConstProjections(SCalcConstContext* pCxt, SSelectStmt* pSelect, bool subquery) {
SNode* pProj = NULL;
WHERE_EACH(pProj, pSelect->pProjectionList) {
if (subquery && !pSelect->isDistinct && isUselessCol((SExprNode*)pProj)) {
ERASE_NODE(pSelect->pProjectionList);
continue;
}
SNode* pNew = NULL;
int32_t code = calcConstProject(pProj, (NULL == pSelect->pFromTable), &pNew);
if (TSDB_CODE_SUCCESS == code) {
REPLACE_NODE(pNew);
} else {
return code;
}
WHERE_NEXT;
}
if (0 == LIST_LENGTH(pSelect->pProjectionList)) {
return nodesListStrictAppend(pSelect->pProjectionList, createConstantValue());
}
return TSDB_CODE_SUCCESS;
}
static int32_t calcConstGroupBy(SCalcConstContext* pCxt, SSelectStmt* pSelect) {
int32_t code = calcConstList(pSelect->pGroupByList);
if (TSDB_CODE_SUCCESS == code) {
SNode* pNode = NULL;
FOREACH(pNode, pSelect->pGroupByList) {
SNode* pGroupPara = NULL;
FOREACH(pGroupPara, ((SGroupingSetNode*)pNode)->pParameterList) {
if (QUERY_NODE_VALUE != nodeType(pGroupPara)) {
return code;
}
}
}
NODES_DESTORY_LIST(pSelect->pGroupByList);
}
return code;
}
static int32_t calcConstSelectWithoutFrom(SCalcConstContext* pCxt, SSelectStmt* pSelect, bool subquery) {
return calcConstProjections(pCxt, pSelect, subquery);
}
static int32_t calcConstSelectFrom(SCalcConstContext* pCxt, SSelectStmt* pSelect, bool subquery) {
int32_t code = calcConstFromTable(pCxt, pSelect->pFromTable);
if (TSDB_CODE_SUCCESS == code) {
code = calcConstProjections(pCxt, pSelect, subquery);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstStmtCondition(pCxt, &pSelect->pWhere, &pSelect->isEmptyResult);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstList(pSelect->pPartitionByList);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstList(pSelect->pTags);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstNode(&pSelect->pSubtable);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstNode(&pSelect->pWindow);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstGroupBy(pCxt, pSelect);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstStmtCondition(pCxt, &pSelect->pHaving, &pSelect->isEmptyResult);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstList(pSelect->pOrderByList);
}
return code;
}
static int32_t calcConstSelect(SCalcConstContext* pCxt, SSelectStmt* pSelect, bool subquery) {
if (NULL == pSelect->pFromTable) {
return calcConstSelectWithoutFrom(pCxt, pSelect, subquery);
} else {
return calcConstSelectFrom(pCxt, pSelect, subquery);
}
}
static int32_t calcConstDelete(SCalcConstContext* pCxt, SDeleteStmt* pDelete) {
int32_t code = calcConstFromTable(pCxt, pDelete->pFromTable);
if (TSDB_CODE_SUCCESS == code) {
code = calcConstStmtCondition(pCxt, &pDelete->pWhere, &pDelete->deleteZeroRows);
}
return code;
}
static int32_t calcConstInsert(SCalcConstContext* pCxt, SInsertStmt* pInsert) {
int32_t code = calcConstFromTable(pCxt, pInsert->pTable);
if (TSDB_CODE_SUCCESS == code) {
code = calcConstQuery(pCxt, pInsert->pQuery, false);
}
return code;
}
static SNodeList* getChildProjection(SNode* pStmt) {
switch (nodeType(pStmt)) {
case QUERY_NODE_SELECT_STMT:
return ((SSelectStmt*)pStmt)->pProjectionList;
case QUERY_NODE_SET_OPERATOR:
return ((SSetOperator*)pStmt)->pProjectionList;
default:
break;
}
return NULL;
}
static void eraseSetOpChildProjection(SSetOperator* pSetOp, int32_t index) {
SNodeList* pLeftProjs = getChildProjection(pSetOp->pLeft);
nodesListErase(pLeftProjs, nodesListGetCell(pLeftProjs, index));
if (QUERY_NODE_SET_OPERATOR == nodeType(pSetOp->pLeft)) {
eraseSetOpChildProjection((SSetOperator*)pSetOp->pLeft, index);
}
SNodeList* pRightProjs = getChildProjection(pSetOp->pRight);
nodesListErase(pRightProjs, nodesListGetCell(pRightProjs, index));
if (QUERY_NODE_SET_OPERATOR == nodeType(pSetOp->pRight)) {
eraseSetOpChildProjection((SSetOperator*)pSetOp->pRight, index);
}
}
typedef struct SNotRefByOrderByCxt {
SColumnNode* pCol;
bool hasThisCol;
} SNotRefByOrderByCxt;
static EDealRes notRefByOrderByImpl(SNode* pNode, void* pContext) {
if (QUERY_NODE_COLUMN == nodeType(pNode)) {
SNotRefByOrderByCxt* pCxt = (SNotRefByOrderByCxt*)pContext;
if (nodesEqualNode((SNode*)pCxt->pCol, pNode)) {
pCxt->hasThisCol = true;
return DEAL_RES_END;
}
}
return DEAL_RES_CONTINUE;
}
static bool notRefByOrderBy(SColumnNode* pCol, SNodeList* pOrderByList) {
SNotRefByOrderByCxt cxt = {.pCol = pCol, .hasThisCol = false};
nodesWalkExprs(pOrderByList, notRefByOrderByImpl, &cxt);
return !cxt.hasThisCol;
}
static bool isSetUselessCol(SSetOperator* pSetOp, int32_t index, SExprNode* pProj) {
if (!isUselessCol(pProj)) {
return false;
}
SNodeList* pLeftProjs = getChildProjection(pSetOp->pLeft);
if (!isUselessCol((SExprNode*)nodesListGetNode(pLeftProjs, index))) {
return false;
}
SNodeList* pRightProjs = getChildProjection(pSetOp->pRight);
if (!isUselessCol((SExprNode*)nodesListGetNode(pRightProjs, index))) {
return false;
}
return true;
}
static int32_t calcConstSetOpProjections(SCalcConstContext* pCxt, SSetOperator* pSetOp, bool subquery) {
if (subquery && pSetOp->opType == SET_OP_TYPE_UNION) {
return TSDB_CODE_SUCCESS;
}
int32_t index = 0;
SNode* pProj = NULL;
WHERE_EACH(pProj, pSetOp->pProjectionList) {
if (subquery && notRefByOrderBy((SColumnNode*)pProj, pSetOp->pOrderByList) &&
isSetUselessCol(pSetOp, index, (SExprNode*)pProj)) {
ERASE_NODE(pSetOp->pProjectionList);
eraseSetOpChildProjection(pSetOp, index);
continue;
}
++index;
WHERE_NEXT;
}
if (0 == LIST_LENGTH(pSetOp->pProjectionList)) {
return nodesListStrictAppend(pSetOp->pProjectionList, createConstantValue());
}
return TSDB_CODE_SUCCESS;
}
static int32_t calcConstSetOperator(SCalcConstContext* pCxt, SSetOperator* pSetOp, bool subquery) {
int32_t code = calcConstSetOpProjections(pCxt, pSetOp, subquery);
if (TSDB_CODE_SUCCESS == code) {
code = calcConstQuery(pCxt, pSetOp->pLeft, false);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstQuery(pCxt, pSetOp->pRight, false);
}
if (TSDB_CODE_SUCCESS == code) {
code = calcConstList(pSetOp->pOrderByList);
}
return code;
}
static int32_t calcConstQuery(SCalcConstContext* pCxt, SNode* pStmt, bool subquery) {
int32_t code = TSDB_CODE_SUCCESS;
switch (nodeType(pStmt)) {
case QUERY_NODE_SELECT_STMT:
code = calcConstSelect(pCxt, (SSelectStmt*)pStmt, subquery);
break;
case QUERY_NODE_EXPLAIN_STMT:
code = calcConstQuery(pCxt, ((SExplainStmt*)pStmt)->pQuery, subquery);
break;
case QUERY_NODE_SET_OPERATOR: {
code = calcConstSetOperator(pCxt, (SSetOperator*)pStmt, subquery);
break;
}
case QUERY_NODE_DELETE_STMT:
code = calcConstDelete(pCxt, (SDeleteStmt*)pStmt);
break;
case QUERY_NODE_INSERT_STMT:
code = calcConstInsert(pCxt, (SInsertStmt*)pStmt);
break;
default:
break;
}
return code;
}
static bool isEmptyResultQuery(SNode* pStmt) {
bool isEmptyResult = false;
switch (nodeType(pStmt)) {
case QUERY_NODE_SELECT_STMT:
isEmptyResult = ((SSelectStmt*)pStmt)->isEmptyResult;
break;
case QUERY_NODE_EXPLAIN_STMT:
isEmptyResult = isEmptyResultQuery(((SExplainStmt*)pStmt)->pQuery);
break;
case QUERY_NODE_SET_OPERATOR: {
SSetOperator* pSetOp = (SSetOperator*)pStmt;
isEmptyResult = isEmptyResultQuery(pSetOp->pLeft);
if (isEmptyResult) {
isEmptyResult = isEmptyResultQuery(pSetOp->pRight);
}
break;
}
default:
break;
}
return isEmptyResult;
}
static void resetProjectNullTypeImpl(SNodeList* pProjects) {
SNode* pProj = NULL;
FOREACH(pProj, pProjects) {
SExprNode* pExpr = (SExprNode*)pProj;
if (TSDB_DATA_TYPE_NULL == pExpr->resType.type) {
pExpr->resType.type = TSDB_DATA_TYPE_VARCHAR;
pExpr->resType.bytes = 0;
}
}
}
static void resetProjectNullType(SNode* pStmt) {
switch (nodeType(pStmt)) {
case QUERY_NODE_SELECT_STMT:
resetProjectNullTypeImpl(((SSelectStmt*)pStmt)->pProjectionList);
break;
case QUERY_NODE_SET_OPERATOR: {
resetProjectNullTypeImpl(((SSetOperator*)pStmt)->pProjectionList);
break;
}
default:
break;
}
}
int32_t calculateConstant(SParseContext* pParseCxt, SQuery* pQuery) {
SCalcConstContext cxt = {.pParseCxt = pParseCxt,
.msgBuf.buf = pParseCxt->pMsg,
.msgBuf.len = pParseCxt->msgLen,
.code = TSDB_CODE_SUCCESS};
int32_t code = calcConstQuery(&cxt, pQuery->pRoot, false);
if (TSDB_CODE_SUCCESS == code) {
resetProjectNullType(pQuery->pRoot);
if (isEmptyResultQuery(pQuery->pRoot)) {
pQuery->execMode = QUERY_EXEC_MODE_EMPTY_RESULT;
}
}
return code;
}