diff --git a/source/common/src/ttime.c b/source/common/src/ttime.c
index 8fbdeb0654..befb0abac8 100644
--- a/source/common/src/ttime.c
+++ b/source/common/src/ttime.c
@@ -589,7 +589,7 @@ int32_t convertStringToTimestamp(int16_t type, char *inputData, int64_t timePrec
       return TSDB_CODE_FAILED;
     }
     newColData[len] = 0;
-    int32_t ret = taosParseTime(newColData, timeVal, len + 1, (int32_t)timePrec, tsDaylight);
+    int32_t ret = taosParseTime(newColData, timeVal, len, (int32_t)timePrec, tsDaylight);
     if (ret != TSDB_CODE_SUCCESS) {
       taosMemoryFree(newColData);
       return ret;
diff --git a/source/libs/function/src/builtins.c b/source/libs/function/src/builtins.c
index e016771bc9..bc004579ba 100644
--- a/source/libs/function/src/builtins.c
+++ b/source/libs/function/src/builtins.c
@@ -1446,19 +1446,9 @@ static int32_t translateSubstr(SFunctionNode* pFunc, char* pErrBuf, int32_t len)
 
 static int32_t translateCast(SFunctionNode* pFunc, char* pErrBuf, int32_t len) {
   // The number of parameters has been limited by the syntax definition
-  // uint8_t para1Type = ((SExprNode*)nodesListGetNode(pFunc->pParameterList, 0))->resType.type;
 
   // The function return type has been set during syntax parsing
   uint8_t para2Type = pFunc->node.resType.type;
-  // if (para2Type != TSDB_DATA_TYPE_BIGINT && para2Type != TSDB_DATA_TYPE_UBIGINT &&
-  //     para2Type != TSDB_DATA_TYPE_VARCHAR && para2Type != TSDB_DATA_TYPE_NCHAR &&
-  //     para2Type != TSDB_DATA_TYPE_TIMESTAMP) {
-  //   return invaildFuncParaTypeErrMsg(pErrBuf, len, pFunc->functionName);
-  // }
-  // if ((para2Type == TSDB_DATA_TYPE_TIMESTAMP && IS_VAR_DATA_TYPE(para1Type)) ||
-  //     (para2Type == TSDB_DATA_TYPE_BINARY && para1Type == TSDB_DATA_TYPE_NCHAR)) {
-  //   return invaildFuncParaTypeErrMsg(pErrBuf, len, pFunc->functionName);
-  // }
 
   int32_t para2Bytes = pFunc->node.resType.bytes;
   if (IS_VAR_DATA_TYPE(para2Type)) {
@@ -1468,6 +1458,11 @@ static int32_t translateCast(SFunctionNode* pFunc, char* pErrBuf, int32_t len) {
     return buildFuncErrMsg(pErrBuf, len, TSDB_CODE_FUNC_FUNTION_ERROR,
                            "CAST function converted length should be in range [0, 1000]");
   }
+
+  // add database precision as param
+  uint8_t dbPrec = pFunc->node.resType.precision;
+  addDbPrecisonParam(&pFunc->pParameterList, dbPrec);
+
   return TSDB_CODE_SUCCESS;
 }
 
diff --git a/source/libs/scalar/src/sclfunc.c b/source/libs/scalar/src/sclfunc.c
index 3a219b78b5..f35f81892d 100644
--- a/source/libs/scalar/src/sclfunc.c
+++ b/source/libs/scalar/src/sclfunc.c
@@ -934,9 +934,16 @@ int32_t castFunction(SScalarParam *pInput, int32_t inputNum, SScalarParam *pOutp
         break;
       }
       case TSDB_DATA_TYPE_TIMESTAMP: {
+        int64_t timeVal;
         if (inputType == TSDB_DATA_TYPE_BINARY || inputType == TSDB_DATA_TYPE_NCHAR) {
-          //convert to 0
-          *(int64_t *)output = 0;
+          int64_t timePrec;
+          GET_TYPED_DATA(timePrec, int64_t, GET_PARAM_TYPE(&pInput[1]), pInput[1].columnData->pData);
+          int32_t ret = convertStringToTimestamp(inputType, input, timePrec, &timeVal);
+          if (ret != TSDB_CODE_SUCCESS) {
+            *(int64_t *)output = 0;
+          } else {
+            *(int64_t *)output = timeVal;
+          }
         } else {
           GET_TYPED_DATA(*(int64_t *)output, int64_t, inputType, input);
         }