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

246 lines
7.7 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"
typedef struct SCalcConstContext {
int32_t code;
} SCalcConstContext;
static int32_t calcConstQuery(SNode* pStmt);
static EDealRes doCalcConst(SNode** pNode, SCalcConstContext* pCxt) {
SNode* pNew = NULL;
pCxt->code = scalarCalculateConstants(*pNode, &pNew);
if (TSDB_CODE_SUCCESS != pCxt->code) {
return DEAL_RES_ERROR;
}
((SValueNode*)pNew)->genByCalc = true;
((SValueNode*)pNew)->translate = true;
*pNode = pNew;
return DEAL_RES_CONTINUE;
}
static EDealRes calcConstOperator(SOperatorNode** pNode, void* pContext) {
SOperatorNode* pOp = *pNode;
if (QUERY_NODE_VALUE == nodeType(pOp->pLeft) && (NULL == pOp->pRight || QUERY_NODE_VALUE == nodeType(pOp->pRight))) {
return doCalcConst((SNode**)pNode, (SCalcConstContext*)pContext);
}
return DEAL_RES_CONTINUE;
}
static EDealRes calcConstFunction(SFunctionNode** pNode, void* pContext) {
SFunctionNode* pFunc = *pNode;
if (!fmIsScalarFunc(pFunc->funcId)) {
return DEAL_RES_CONTINUE;
}
SNode* pParam = NULL;
FOREACH(pParam, pFunc->pParameterList) {
if (QUERY_NODE_VALUE != nodeType(pParam)) {
return DEAL_RES_CONTINUE;
}
}
return doCalcConst((SNode**)pNode, (SCalcConstContext*)pContext);
}
static EDealRes calcConstLogicCond(SLogicConditionNode** pNode, void* pContext) {
SLogicConditionNode* pCond = *pNode;
SNode* pParam = NULL;
FOREACH(pParam, pCond->pParameterList) {
// todo calc "true and c1 > 10"
if (QUERY_NODE_VALUE != nodeType(pParam)) {
return DEAL_RES_CONTINUE;
}
}
return doCalcConst((SNode**)pNode, (SCalcConstContext*)pContext);
}
static EDealRes calcConstSubquery(STempTableNode** pNode, void* pContext) {
SCalcConstContext* pCxt = pContext;
pCxt->code = calcConstQuery((*pNode)->pSubquery);
return (TSDB_CODE_SUCCESS == pCxt->code ? DEAL_RES_CONTINUE : DEAL_RES_ERROR);
}
static EDealRes calcConst(SNode** pNode, void* pContext) {
switch (nodeType(*pNode)) {
case QUERY_NODE_OPERATOR:
return calcConstOperator((SOperatorNode**)pNode, pContext);
case QUERY_NODE_FUNCTION:
return calcConstFunction((SFunctionNode**)pNode, pContext);
case QUERY_NODE_LOGIC_CONDITION:
return calcConstLogicCond((SLogicConditionNode**)pNode, pContext);
case QUERY_NODE_TEMP_TABLE:
return calcConstSubquery((STempTableNode**)pNode, pContext);
default:
break;
}
return DEAL_RES_CONTINUE;
}
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 = 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 rewriteConditionForFromTable(SCalcConstContext* pCxt, SNode* pTable) {
if (QUERY_NODE_JOIN_TABLE == nodeType(pTable)) {
SJoinTableNode* pJoin = (SJoinTableNode*)pTable;
pCxt->code = rewriteConditionForFromTable(pCxt, pJoin->pLeft);
if (TSDB_CODE_SUCCESS == pCxt->code) {
pCxt->code = rewriteConditionForFromTable(pCxt, pJoin->pRight);
}
if (TSDB_CODE_SUCCESS == pCxt->code) {
pCxt->code = rewriteCondition(pCxt, &pJoin->pOnCond);
}
}
return pCxt->code;
}
static void rewriteConstCondition(SSelectStmt* pSelect, SNode** pCond) {
if (QUERY_NODE_VALUE != nodeType(*pCond)) {
return;
}
if (((SValueNode*)*pCond)->datum.b) {
nodesDestroyNode(*pCond);
*pCond = NULL;
} else {
pSelect->isEmptyResult = true;
}
}
static int32_t calcConstFromTable(SCalcConstContext* pCxt, SSelectStmt* pSelect) {
pCxt->code = rewriteConditionForFromTable(pCxt, pSelect->pFromTable);
if (TSDB_CODE_SUCCESS == pCxt->code) {
nodesRewriteExprPostOrder(&pSelect->pFromTable, calcConst, pCxt);
}
return pCxt->code;
}
static int32_t calcConstCondition(SCalcConstContext* pCxt, SSelectStmt* pSelect, SNode** pCond) {
if (NULL == *pCond) {
return TSDB_CODE_SUCCESS;
}
pCxt->code = rewriteCondition(pCxt, pCond);
if (TSDB_CODE_SUCCESS == pCxt->code) {
nodesRewriteExprPostOrder(pCond, calcConst, pCxt);
}
if (TSDB_CODE_SUCCESS == pCxt->code) {
rewriteConstCondition(pSelect, pCond);
}
return pCxt->code;
}
static int32_t calcConstSelect(SSelectStmt* pSelect) {
SCalcConstContext cxt = { .code = TSDB_CODE_SUCCESS };
nodesRewriteExprsPostOrder(pSelect->pProjectionList, calcConst, &cxt);
if (TSDB_CODE_SUCCESS == cxt.code) {
cxt.code = calcConstFromTable(&cxt, pSelect);
}
if (TSDB_CODE_SUCCESS == cxt.code) {
cxt.code = calcConstCondition(&cxt, pSelect, &pSelect->pWhere);
}
if (TSDB_CODE_SUCCESS == cxt.code) {
nodesRewriteExprsPostOrder(pSelect->pPartitionByList, calcConst, &cxt);
}
if (TSDB_CODE_SUCCESS == cxt.code) {
nodesRewriteExprPostOrder(&pSelect->pWindow, calcConst, &cxt);
}
if (TSDB_CODE_SUCCESS == cxt.code) {
nodesRewriteExprsPostOrder(pSelect->pGroupByList, calcConst, &cxt);
}
if (TSDB_CODE_SUCCESS == cxt.code) {
cxt.code = calcConstCondition(&cxt, pSelect, &pSelect->pHaving);
}
if (TSDB_CODE_SUCCESS == cxt.code) {
nodesRewriteExprsPostOrder(pSelect->pOrderByList, calcConst, &cxt);
}
return cxt.code;
}
static int32_t calcConstQuery(SNode* pStmt) {
switch (nodeType(pStmt)) {
case QUERY_NODE_SELECT_STMT:
return calcConstSelect((SSelectStmt*)pStmt);
case QUERY_NODE_EXPLAIN_STMT:
return calcConstQuery(((SExplainStmt*)pStmt)->pQuery);
default:
break;
}
return TSDB_CODE_SUCCESS;
}
static bool isEmptyResultQuery(SNode* pStmt) {
switch (nodeType(pStmt)) {
case QUERY_NODE_SELECT_STMT:
return ((SSelectStmt*)pStmt)->isEmptyResult;
case QUERY_NODE_EXPLAIN_STMT:
return isEmptyResultQuery(((SExplainStmt*)pStmt)->pQuery);
default:
break;
}
return false;
}
int32_t calculateConstant(SParseContext* pParseCxt, SQuery* pQuery) {
int32_t code = calcConstQuery(pQuery->pRoot);
if (TSDB_CODE_SUCCESS == code) {
pQuery->execMode = isEmptyResultQuery(pQuery->pRoot) ? QUERY_EXEC_MODE_EMPTY_RESULT : pQuery->execMode;
}
return code;
}