The column names being selected willīe automatically quoted when the SQL statement is being generated from a query object. You can specifyĬolumns to be selected in either an array or a string, like the following. The select() method specifies the SELECT fragment of a SQL statement. In the following, we will describe the usage of each query building method. For example, to specify the FROM part of a SQL query, you would call the from() method.Īll the query building methods return the query object itself, which allows you to chain multiple calls together.
The names of these methods resemble the SQL keywords used in the corresponding parts of the SQL To build a yii\db\Query object, you call different query building methods to specify different parts ofĪ SQL query. quoting table/column names differently) from DBMS-independent yii\db\QueryBuilder is the class responsibleįor generating DBMS-dependent SQL statements (e.g. The latter is invokedīy the former implicitly when you call one of the query methods. Info: You usually mainly work with yii\db\Query instead of yii\db\QueryBuilder. SELECT `id`, `email` FROM `user` WHERE `last_name` = :last_name
Mysql union select from inner select code#
The above code generates and executes the following SQL query, where the :last_name parameter is bound with the The following code shows a typical way of using query builder: $rows = ( new \yii\db\Query()) all()) of yii\db\Query to retrieve data from the database. Build a yii\db\Query object to represent different parts (e.g.
Using query builder usually involves two steps: More readable SQL-related code and generate more secure SQL statements. Compared to writing raw SQL statements, using query builder will help you write Built on top of Database Access Objects, query builder allows you to construct a SQL query
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