在使用Golang进行数据库操作时,我们经常会使用`db.Model(&Usertable).Create(data)`这样的代码来创建新的数据。然而,有时候我们可能会遇到一个问题:如何传递正确的表名?在这篇文章中,php小编柚子将详细解答这个问题,帮助读者更好地理解如何正确地传递表名,以便顺利进行数据库操作。
问题内容
我正在尝试将一行插入定义为模型的表中。以下是相关代码片段:
包结构:
gorm
|- server
|- insertRow.go
|- pkg
|- models
|- mytable.go
|- database
| - connectdb.go
mytable.go:
package models
type Usertable struct {
Firstname string `gorm:"column:firstname"`
Lastname string `gorm:"column:lastname"`
}
func (fmap *Usertable) TableName() string { return "usertable" }
insertRow.go
package main
import (
"fmt"
"gorm/pkg/models"
"gorm/pkg/database"
)
func main() {
params := map[string]interface{} {
"Firstname" : "MyFirstName",
"Lastname" : "LastName" ,
}
db, _ := database.NewStorage("postgres", "testdb")
var user models.Usertable
err := db.DB.Debug().Model(&user).Create(params)
if err != nil {
fmt.Println("Error :=", err)
} else {
fmt.Println("Success")
}
}
表定义:
testdb=# d+ usertable
Table "public.usertable"
Column | Type | Collation | Nullable | Default | Storage | Stats target | Description
-----------+------+-----------+----------+---------+----------+--------------+-------------
firstname | text | | | | extended | |
lastname | text | | | | extended | |
执行 insertRow.go 会出现以下错误:
(/root/gorm/cloudOps/server/testDB/insertRow.go:17)
[2023-09-23 23:51:26] pq: zero-length delimited identifier at or near """"
(/root/gorm/cloudOps/server/testDB/insertRow.go:17)
[2023-09-23 23:51:26] [0.45ms] **INSERT INTO "" DEFAULT VALUES RETURNING "".***
[0 rows affected or returned ]
Error := &{{{0 0} 0 0 {{} 0} {{} 0}} map[Firstname:MyFirstName Lastname:LastName] pq: zero-length delimited identifier at or near """" 0 0xc0000a4b60 false 2 {0xc0001a3d60} 0xc0001e8420 {{0 0} {[] {} 0xc00021cc20} map[] 0} 0xc0000a4c30 <nil> 0xc0000a2c78 false <nil>}
插入命令中的表名似乎为空,请让我知道我的插入命令出了什么问题以及如何将正确的表名传递给 Create 调用。
我也尝试过,结果相同:
package main
import (
"fmt"
// "gorm/pkg/models"
"gorm/pkg/database"
"gorm.io/gorm"
)
type Usertable struct {
gorm.Model
Firstname string `gorm:"column:firstname"`
Lastname string `gorm:"column:lastname"`
}
func main() {
params := map[string]interface{} {
"Firstname" : "MyFirstName",
"Lastname" : "LastName" ,
}
db, _ := database.NewStorage("postgres", "testdb")
err := db.DB.Debug().Model(&Usertable{}).Create(params)
if err != nil {
fmt.Println("Error :=", err)
} else {
fmt.Println("Success")
}
}
解决方法
您设置了一个要插入的map[string]interface{},但gorm希望传递一个结构
user := models.Usertable{
Firstname: "MyFirstName",
Lastname: "LastName",
}
result := db.DB.Debug().Create(&user)