没有命名空间的类 yii yii\base yii\behaviors yii\caching yii\captcha yii\console yii\console\controllers yii\console\widgets yii\data yii\db yii\db\conditions yii\db\cubrid yii\db\cubrid\conditions yii\db\mssql yii\db\mssql\conditions yii\db\mysql yii\db\oci yii\db\oci\conditions yii\db\pgsql yii\db\sqlite yii\db\sqlite\conditions yii\di yii\filters yii\filters\auth yii\grid yii\helpers yii\i18n yii\log yii\mail yii\mutex yii\rbac yii\rest yii\test yii\validators yii\web yii\widgets

Interface yii\db\ExpressionInterface

实现yii\db\ActiveQuery, yii\db\ArrayExpression, yii\db\Expression, yii\db\JsonExpression, yii\db\PdoValue, yii\db\Query, yii\db\conditions\ConditionInterface
可用版本自2.0.14
源码 https://github.com/yiichina/yii2/blob/api/framework/db/ExpressionInterface.php

接口 ExpressionInterface 应用于标记类, 这些类应以特殊方式构建。

Yii 框架的数据库抽象层支持实现此接口的对象, 并将使用 yii\db\ExpressionBuilderInterface 来构建它们。

默认实现是一个类 yii\db\Expression