GORM 提供的配置可以在初始化时使用

type Config struct {
  SkipDefaultTransaction   bool
  NamingStrategy           schema.Namer
  Logger                   logger.Interface
  NowFunc                  func() time.Time
  DryRun                   bool
  PrepareStmt              bool
  DisableNestedTransaction bool
  AllowGlobalUpdate        bool
  DisableAutomaticPing     bool
  DisableForeignKeyConstraintWhenMigrating bool
}

跳过默认事务

为了确保数据一致性，GORM 会在事务里执行写入操作（创建、更新、删除）。如果没有这方面的要求，您可以在初始化时禁用它。

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  SkipDefaultTransaction: true,
})

命名策略

GORM 允许用户通过覆盖默认的命名策略更改默认的命名约定，这需要实现接口 Namer

type Namer interface {
    TableName(table string) string
    ColumnName(table, column string) string
    JoinTableName(table string) string
    RelationshipFKName(Relationship) string
    CheckerName(table, column string) string
    IndexName(table, column string) string
}

默认 NamingStrategy 也提供了几个选项，如：

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  NamingStrategy: schema.NamingStrategy{
    TablePrefix: "t_",   // 表名前缀，`User` 的表名应该是 `t_users`
    SingularTable: true, // 使用单数表名，启用该选项，此时，`User` 的表名应该是 `t_user`
  },
})

Logger

允许通过覆盖此选项更改 GORM 的默认 logger，参考 Logger 获取详情

NowFunc

更改创建时间使用的函数

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  NowFunc: func() time.Time {
    return time.Now().Local()
  },
})

DryRun

生成 SQL 但不执行，可以用于准备或测试生成的 SQL，参考 会话 获取详情

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  DryRun: false,
})

PrepareStmt

PreparedStmt 在执行任何 SQL 时都会创建一个 prepared statement 并将其缓存，以提高后续的效率，参考 会话 获取详情

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  PrepareStmt: false,
})

DisableNestedTransaction

When using Transaction method inside a db transaction, GORM will use SavePoint(savedPointName), RollbackTo(savedPointName) to give you the nested transaction support, you could disable it by using the DisableNestedTransaction option, refer Session for details

AllowGlobalUpdate

Enable global update/delete, refer Session for details

DisableAutomaticPing

GORM automatically ping database after initialized to check database availability, disable it by setting it to true

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  DisableAutomaticPing: true,
})

DisableForeignKeyConstraintWhenMigrating

GORM creates database foreign key constraints automatically when AutoMigrate or CreateTable, disable this by setting it to true, refer Migration for details

db, err := gorm.Open(sqlite.Open("gorm.db"), &gorm.Config{
  DisableForeignKeyConstraintWhenMigrating: true,
})