fix: resolved timestamp formatting issue in REST flow

Author: sachinpro

google/cloud/odbc/bq_driver/internal/odbc_internal_commons.h

@@ -309,8 +309,8 @@ inline std::string FormatDatetimeToString(
     const SQL_TIMESTAMP_STRUCT& datetime) {
   char buffer[30];
   auto const* datetime_format = (datetime.fraction == 0)
-                                    ? "%04d-%02d-%02dT%02d:%02d:%02d"
-                                    : "%04d-%02d-%02dT%02d:%02d:%02d.%06d";
+                                    ? "%04d-%02d-%02d %02d:%02d:%02d"
+                                    : "%04d-%02d-%02d %02d:%02d:%02d.%06d";
   snprintf(buffer, sizeof(buffer), datetime_format, datetime.year,
            datetime.month, datetime.day, datetime.hour, datetime.minute,
            datetime.second, datetime.fraction);

google/cloud/odbc/bq_driver/internal/odbc_internal_commons_test.cc

@@ -269,7 +269,7 @@ TEST(FormatDatetimeToString, DatetimeStringWithZeros) {
 
   std::string datetime_string = FormatDatetimeToString(datetime);
 
-  std::string expected_string = "2020-01-10T00:05:03";
+  std::string expected_string = "2020-01-10 00:05:03";
   EXPECT_EQ(datetime_string, expected_string);
 }
 
@@ -285,7 +285,7 @@ TEST(FormatDatetimeToString, DatetimeString) {
 
   std::string datetime_string = FormatDatetimeToString(datetime);
 
-  std::string expected_string = "2020-01-10T01:59:43.123456";
+  std::string expected_string = "2020-01-10 01:59:43.123456";
   EXPECT_EQ(datetime_string, expected_string);
 }
 

google/cloud/odbc/bq_driver/internal/odbc_sql_execute_utils.cc

@@ -306,9 +306,16 @@ StatusRecordOr<std::shared_ptr<arrow::Schema>> GetArrowSchema(
       case arrow::Type::BOOL:
         col_schema.col_type = BQDataType::kBool;
         break;
-      case arrow::Type::TIMESTAMP:
-        col_schema.col_type = BQDataType::kTimeStamp;
+      case arrow::Type::TIMESTAMP: {
+        auto ts_type =
+            std::static_pointer_cast<arrow::TimestampType>(field->type());
+        if (ts_type->timezone().empty()) {
+          col_schema.col_type = BQDataType::kDatetime;
+        } else {
+          col_schema.col_type = BQDataType::kTimeStamp;
+        }
         break;
+      }
       case arrow::Type::TIME64:
         col_schema.col_type = BQDataType::kTime;
         break;

google/cloud/odbc/integration_tests/odbc_driver_tests/data_translation_test.cc

@@ -2486,19 +2486,13 @@ void TestTranslationsFromDateTime(std::shared_ptr<ODBCHandles> conn,
     switch (expected.target_c_type) {
       case SQL_C_CHAR: {
         std::string returned_val = reinterpret_cast<char*>(data);
-        if (kIsBqDriver) {
-          expected_val = FormatToGoogleDatetimeStr(expected_val);
-        }
         EXPECT_EQ(returned_val, expected_val);
         break;
       }
       case SQL_C_WCHAR: {
         SQLINTEGER length = strlen_or_ind / sizeof(SQLWCHAR);
         std::string returned_val =
             ConvertSQLWCHARToString(reinterpret_cast<SQLWCHAR*>(data), length);
-        if (kIsBqDriver) {
-          expected_val = FormatToGoogleDatetimeStr(expected_val);
-        }
         EXPECT_STREQ(returned_val.data(), expected_val.data());
         break;
       }

google/cloud/odbc/integration_tests/odbc_driver_tests/statement_test.cc

@@ -529,11 +529,11 @@ static RowWiseResults const kBasicTypesExpected{
         {7, "2025-11-12 23:22:27.500000"},
         {8, kIsBqDriver ? "12:34:56" : "12:34:56.000000"},
         {9, kIsBqDriver
-                ? (kIsWin32 ? "2024-05-01T08:00:00" : "2024-05-01 08:00:00")
+                ? "2024-05-01 08:00:00"
                 : "2024-05-01 08:00:00.000000"},
         {10, "2023-04-01"},
         {11, kIsBqDriver
-                 ? (kIsWin32 ? "[\"3\",\"4\",\"5\"]" : "[3, 4, 5]")
+                 ? "[\"3\",\"4\",\"5\"]"
                  : "{\"v\":[{\"v\":\"3\"},{\"v\":\"4\"},{\"v\":\"5\"}]}"},
     }},
 };