laravel exists怎么使用
laravel exists怎么使用?
exists:table,column
验证字段的值是否存在于数据库指定表的指定列中,如果不存在将会抛出异常,这里是关于 exists 规则的
基本用法
验证 users 表中是否存在 email 等于指定的 email 值的记录
'email' => 'exists:users' Rule::exists('users')
自定义列名
验证 users 表的 email_address
'email' => 'exists:users,email_address' Rule::exists('users','email_address')
自定义数据库连接
验证指定数据库连接的 users 表
'email' => 'exists:connection.users,email'
附加 WHERE 条件(可以有多个)
除了验证 email_address 还需要验证 role 等于 admin
'email' => 'exists:users,email_address,role,admin' Rule::exists('users','email_address')->where('role','admin')
! 表示不等于
'email' => 'exists:users,email_address,role,!admin' Rule::exists('users','email_address')->whereNot('role','admin')
NULL 在 MySQL 中是通过 IS 判断的,这里注意不用 IS
'email' => 'exists:users,email,deleted_at,NULL' Rule::exists('users','email_address')->whereNull('deleted_at')
对不等于 NULL 的情况不能使用 !,而是使用 NOT_NULL
'email' => 'exists:users,email,deleted_at,NOT_NULL' Rule::exists('users','email_address')->whereNotNull('deleted_at')
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