Go读取MySQL Date类型的避坑指南

CREATE TABLE `t_test` (
  `id` int NOT NULL AUTO_INCREMENT,
  `f_one` datetime DEFAULT NULL,
  `f_two` date DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

INSERT INTO `test`.`t_test` (`f_one`, `f_two`) VALUES ('2025-11-29 10:25:05', '2025-11-29');

mysql> select * from t_test where id = 1;
+----+---------------------+------------+
| id | f_one               | f_two      |
+----+---------------------+------------+
|  1 | 2025-11-29 10:25:05 | 2025-11-29 |
+----+---------------------+------------+
1 row in set (0.003 sec)

package main

import (
	"testing"

	"github.com/stretchr/testify/assert"
	"gorm.io/driver/mysql"
	"gorm.io/gorm"
)

type Test struct {
	ID   int    `gorm:"column:id;primaryKey"`
	FOne string `gorm:"column:f_one"` // 注意这里我们定义成了string类型
	FTwo string `gorm:"column:f_two"` // 注意这里我们定义成了string类型
}

func (t Test) TableName() string {
	return "t_test"
}

func TestRead(t *testing.T) {
	// 数据库连接配置
	dsn := "root:root@tcp(127.0.0.1:3306)/test?charset=utf8mb4&parseTime=True&loc=Local"

	db, err := gorm.Open(mysql.Open(dsn))
	assert.Nil(t, err)

	var result Test
	err = db.Where("id = ?", 1).Find(&result).Error
	assert.Nil(t, err)

	assert.Equal(t, "2025-11-29 10:25:05", result.FOne)
	assert.Equal(t, "2025-11-29", result.FTwo)
}

Error: Not equal: 
       expected: "2025-11-29 10:25:05"
       actual  : "2025-11-29T10:25:05+08:00"

Error: Not equal: 
       expected: "2025-11-29"
       actual  : "2025-11-29T00:00:00+08:00"

# 开启parseTime=true且Go类型定义为string时

`DATETIME(MySQL)` 
      |
      v
`time.Time`(golang) 
      |
      | ->这里的`time.time`到`string`这一步出现了转化差异
      v
`string(golang)`          

type Test struct {
	ID   int       `gorm:"column:id;primaryKey"`
	FOne time.Time `gorm:"column:f_one"`
	FTwo time.Time `gorm:"column:f_two"`
}

type Test struct {
	ID   int    `gorm:"column:id;primaryKey"`
	FOne string `gorm:"column:f_one"`
	FTwo string `gorm:"column:f_two"`
}