feat(query): support now()/today() function in select clause

TD-14243

include/libs/scalar/scalar.h

@@ -78,6 +78,8 @@ int32_t toISO8601Function(SScalarParam *pInput, int32_t inputNum, SScalarParam *
 int32_t toUnixtimestampFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 int32_t timeTruncateFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 int32_t timeDiffFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
+int32_t nowFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
+int32_t todayFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput);
 
 bool getTimePseudoFuncEnv(struct SFunctionNode* pFunc, SFuncExecEnv* pEnv);
 

source/libs/function/src/builtins.c

@@ -433,6 +433,26 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
     .sprocessFunc = timeDiffFunction,
     .finalizeFunc = NULL
   },
+  {
+    .name = "now",
+    .type = FUNCTION_TYPE_NOW,
+    .classification = FUNC_MGT_SCALAR_FUNC | FUNC_MGT_DATETIME_FUNC,
+    .checkFunc    = checkAndGetResultType,
+    .getEnvFunc   = NULL,
+    .initFunc     = NULL,
+    .sprocessFunc = nowFunction,
+    .finalizeFunc = NULL
+  },
+  {
+    .name = "today",
+    .type = FUNCTION_TYPE_TODAY,
+    .classification = FUNC_MGT_SCALAR_FUNC | FUNC_MGT_DATETIME_FUNC,
+    .checkFunc    = checkAndGetResultType,
+    .getEnvFunc   = NULL,
+    .initFunc     = NULL,
+    .sprocessFunc = todayFunction,
+    .finalizeFunc = NULL
+  },
   {
     .name = "_rowts",
     .type = FUNCTION_TYPE_ROWTS,
@@ -503,16 +523,6 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
     .sprocessFunc = winDurFunction,
     .finalizeFunc = NULL
   },
-  {
-    .name = "now",
-    .type = FUNCTION_TYPE_NOW,
-    .classification = FUNC_MGT_SCALAR_FUNC | FUNC_MGT_DATETIME_FUNC,
-    .checkFunc    = checkAndGetResultType,
-    .getEnvFunc   = getTimePseudoFuncEnv,
-    .initFunc     = NULL,
-    .sprocessFunc = winDurFunction,
-    .finalizeFunc = NULL
-  }
 };
 
 const int32_t funcMgtBuiltinsNum = (sizeof(funcMgtBuiltins) / sizeof(SBuiltinFuncDefinition));
@@ -672,7 +682,8 @@ int32_t checkAndGetResultType(SFunctionNode* pFunc) {
     }
 
     case FUNCTION_TYPE_NOW:
-      // todo
+    case FUNCTION_TYPE_TODAY:
+      pFunc->node.resType = (SDataType) { .bytes = tDataTypes[TSDB_DATA_TYPE_TIMESTAMP].bytes, .type = TSDB_DATA_TYPE_TIMESTAMP};
       break;
     default:
       ASSERT(0); // to found the fault ASAP.

source/libs/parser/inc/parAst.h

@@ -93,6 +93,7 @@ SNode* createOperatorNode(SAstCreateContext* pCxt, EOperatorType type, SNode* pL
 SNode* createBetweenAnd(SAstCreateContext* pCxt, SNode* pExpr, SNode* pLeft, SNode* pRight);
 SNode* createNotBetweenAnd(SAstCreateContext* pCxt, SNode* pExpr, SNode* pLeft, SNode* pRight);
 SNode* createFunctionNode(SAstCreateContext* pCxt, const SToken* pFuncName, SNodeList* pParameterList);
+SNode* createFunctionNodeNoParam(SAstCreateContext* pCxt, const SToken* pFuncName);
 SNode* createNodeListNode(SAstCreateContext* pCxt, SNodeList* pList);
 SNode* createNodeListNodeEx(SAstCreateContext* pCxt, SNode* p1, SNode* p2);
 SNode* createRealTableNode(SAstCreateContext* pCxt, SToken* pDbName, SToken* pTableName, SToken* pTableAlias);

source/libs/parser/inc/sql.y

@@ -503,6 +503,8 @@ column_name(A) ::= NK_ID(B).
 function_name(A) ::= NK_ID(B).                                                    { A = B; }
 function_name(A) ::= FIRST(B).                                                    { A = B; }
 function_name(A) ::= LAST(B).                                                     { A = B; }
+function_name(A) ::= NOW(B).                                                      { A = B; }
+function_name(A) ::= TODAY(B).                                                    { A = B; }
 
 %type table_alias                                                                 { SToken }
 %destructor table_alias                                                           { }
@@ -535,6 +537,7 @@ expression(A) ::= pseudo_column(B).
 expression(A) ::= column_reference(B).                                            { A = B; }
 expression(A) ::= function_name(B) NK_LP expression_list(C) NK_RP(D).             { A = createRawExprNodeExt(pCxt, &B, &D, createFunctionNode(pCxt, &B, C)); }
 expression(A) ::= function_name(B) NK_LP NK_STAR(C) NK_RP(D).                     { A = createRawExprNodeExt(pCxt, &B, &D, createFunctionNode(pCxt, &B, createNodeList(pCxt, createColumnNode(pCxt, NULL, &C)))); }
+expression(A) ::= function_name(B) NK_LP NK_RP(D).                                { A = createRawExprNodeExt(pCxt, &B, &D, createFunctionNodeNoParam(pCxt, &B)); }
 //for CAST function CAST(expr AS type_name)
 expression(A) ::= function_name(B) NK_LP expression(C) AS type_name(D) NK_RP(E).  {
                                                                                     SNodeList *p = createNodeList(pCxt, releaseRawExprNode(pCxt, C));
@@ -587,8 +590,8 @@ expression_list(A) ::= expression_list(B) NK_COMMA expression(C).
 column_reference(A) ::= column_name(B).                                           { A = createRawExprNode(pCxt, &B, createColumnNode(pCxt, NULL, &B)); }
 column_reference(A) ::= table_name(B) NK_DOT column_name(C).                      { A = createRawExprNodeExt(pCxt, &B, &C, createColumnNode(pCxt, &B, &C)); }
 
-pseudo_column(A) ::=  NOW(B).                                                     { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
-pseudo_column(A) ::=  TODAY(B).                                                   { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
+//pseudo_column(A) ::=  NOW(B).                                                     { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
+//pseudo_column(A) ::=  TODAY(B).                                                   { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
 pseudo_column(A) ::=  ROWTS(B).                                                   { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
 pseudo_column(A) ::=  TBNAME(B).                                                  { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }
 pseudo_column(A) ::=  QSTARTTS(B).                                                { A = createRawExprNode(pCxt, &B, createFunctionNode(pCxt, &B, NULL)); }

source/libs/parser/src/parAstCreater.c

@@ -367,6 +367,39 @@ SNode* createFunctionNode(SAstCreateContext* pCxt, const SToken* pFuncName, SNod
   return (SNode*)func;
 }
 
+SNode* createFunctionNodeNoParam(SAstCreateContext* pCxt, const SToken* pFuncName) {
+  SFunctionNode* func = (SFunctionNode*)nodesMakeNode(QUERY_NODE_FUNCTION);
+  CHECK_OUT_OF_MEM(func);
+  char buf[64] = {0};
+
+  int32_t dataType;
+  switch (pFuncName->type) {
+    case TK_NOW: {
+      int64_t ts = taosGetTimestamp(TSDB_TIME_PRECISION_MILLI);
+      snprintf(buf, sizeof(buf), "%"PRId64, ts);
+      dataType = TSDB_DATA_TYPE_BIGINT;
+      break;
+    }
+    case TK_TODAY: {
+      int64_t ts = taosGetTimestampToday(TSDB_TIME_PRECISION_MILLI);
+      snprintf(buf, sizeof(buf), "%"PRId64, ts);
+      dataType = TSDB_DATA_TYPE_BIGINT;
+      break;
+    }
+    //case TK_TIMEZONE: {
+    //  strncpy(buf, tsTimezoneStr, strlen(tsTimezoneStr));
+    //  dataType = TSDB_DATA_TYPE_BINARY;
+    //  break;
+    //}
+  }
+  SToken token = {.type = pFuncName->type, .n = strlen(buf), .z = buf};
+
+  SNodeList *pParameterList = createNodeList(pCxt, createValueNode(pCxt, dataType, &token));
+  strncpy(func->functionName, pFuncName->z, pFuncName->n);
+  func->pParameterList = pParameterList;
+  return (SNode*)func;
+}
+
 SNode* createNodeListNode(SAstCreateContext* pCxt, SNodeList* pList) {
   SNodeListNode* list = (SNodeListNode*)nodesMakeNode(QUERY_NODE_NODE_LIST);
   CHECK_OUT_OF_MEM(list);

source/libs/scalar/src/sclfunc.c

@@ -1242,6 +1242,22 @@ int32_t timeDiffFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *p
   return TSDB_CODE_SUCCESS;
 }
 
+int32_t nowFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput) {
+  if (inputNum != 1) {
+    return TSDB_CODE_FAILED;
+  }
+  colDataAppendInt64(pOutput->columnData, pOutput->numOfRows, (int64_t *)colDataGetData(pInput->columnData, 0));
+  return TSDB_CODE_SUCCESS;
+}
+
+int32_t todayFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput) {
+  if (inputNum != 1) {
+    return TSDB_CODE_FAILED;
+  }
+  colDataAppendInt64(pOutput->columnData, pOutput->numOfRows, (int64_t *)colDataGetData(pInput->columnData, 0));
+  return TSDB_CODE_SUCCESS;
+}
+
 int32_t atanFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutput) {
   return doScalarFunctionUnique(pInput, inputNum, pOutput, atan);
 }