如何指定数组gorm golang的默认值？

Posted 2023-02-16

【中文标题】如何指定数组gorm golang的默认值？

【英文标题】：how to specify default value of array gorm golang?

【发布时间】：2022-01-11 22:44:30

【问题描述】：

我用的是gorm和postgresql，这是模型

type Board struct 
    Id     uint `gorm:"primaryKey;autoIncrement;unique" json:"id"`
    Owner  uint `json:"owner"`
    Name string `json:"name"`
    Contributors []int `gorm:"type:jsonb" json:"contributors"`
    GeneratedLink string `gorm:"default:''" json:"generated_link"`
    Todos []TodoStructure `gorm:"type:jsonb;default:[]" json:"todos"`


type TodoStructure struct 
    Id string
    Text string
    Completed bool
    Important bool

在 Todo 值中，我将默认值指定为 [] 但是当我运行应用程序时出现此错误

ERROR: syntax error at or near "[" (SQLSTATE 42601)
[100.528ms] [rows:0] CREATE TABLE "boards" ("id" bigserial UNIQUE,"owner" bigint,"name" text,"contributors" jsonb,"generated_link" text DEFAULT '',"todos" jsonb DEFAULT [],PRIMARY KEY ("id"))
panic: ERROR: syntax error at or near "[" (SQLSTATE 42601)

那么如何指定数组为默认值呢？

【参考方案1】：

尝试像这样引用gorm:"type:jsonb;default:'[]'" json:"todos"

type Board struct 
    Id     uint `gorm:"primaryKey;autoIncrement;unique" json:"id"`
    Owner  uint `json:"owner"`
    Name string `json:"name"`
    Contributors []int `gorm:"type:jsonb" json:"contributors"`
    GeneratedLink string `gorm:"default:''" json:"generated_link"`
    Todos []TodoStructure `gorm:"type:jsonb;default:'[]'" json:"todos"`

更多参考你可以参考这个link

【讨论】：

现在尝试创建板时出现错误：sql: Scan error on column index 1, name "todos": unsupported Scan, storing driver.Value type []uint8 into type *[]models.TodoStructure