Summary of database query operations of PHP Yii framework

Yii is easy to learn and use. You only need to know PHP and object-oriented programming, and you can get started quickly without having to learn a new architecture or template language in advance. Development with Yii is very fast and requires very little coding to be written for the application other than the framework itself. In fact it is one of the most efficient development frameworks. How much do you know about the method of database query data under the Yii framework? Today the editor has made a summary for everyone.

Summary of methods for database query data under the yii framework.

(1)

$result=Yii::app()->dbName->createCommand($sql)->queryRow();

The result set returned is a one-dimensional array if it is not empty. The dbName in the code is the name of the library where the data table is located, and $sql can be any SQL statement.

(2)

$result=Yii::app()->dbName->createCommand($sql)->queryAll();

The result set returned is a two-dimensional array if it is not empty. The dbName in the code is the name of the library where the data table is located, and $sql can be any SQL statement.

(3)

$result=Region::model()->findByPk($id);

The returned result is an object if it is not empty. The Region in the code represents the Region.php file stored in the models directory. The $id here The value represents the value equal to the primary key defined in Region.php.

(4)

$result=Region::model()->findAll($condition,$params);

For example:

findAll("username=:name",array(":name"=>$username));

The result set returned is a two-dimensional array if it is not empty, and the result set in the first dimension of the array is an object. .

(5)

$admin=User::model()->findAllByPk($postIDs,$condition,$params);

For example:

findAllByPk($id,"name like ':name' and age=:age",array(':name'=>$name,'age'=>$age));

This method queries a set based on the primary key. If the returned result set is not empty, it will be a two-dimensional array. The result set of the first dimension of the array is an object. You can also use multiple primary keys, such as: findAllByPk(array(1,2));

(6)

$admin=User::model()->findAllBySql($sql,$params);

The result set returned will be a two-dimensional array if it is not empty. , the result set of the first dimension of the array is an object. Examples of use are:

findAllBySql("select * from admin where username=:name",array(':name'=>'admin'));

(7)

$post=Post::model()->findBySql($sql,$params);

The result set returned is an object if it is not empty, and the query result is only the first A piece of data. For example:

findBySql("select * from user where username=:name",array(':name'=>'phpernote.com'));

(8)

$row=User::model()->find($condition,$params);

The result set returned is an object if it is not empty, and the query result is only the first piece of data. For example:

find('username=:name',array(':name'=>'admin'));

or:

find(array('condition'=>'user_id=:user_id','params'=>array(':user_id'=>$uid)));

(9)

$admin=User::model()->findByAttributes($attributes,$condition,$params);

This method is to query data based on conditions, which can be multiple conditions. Put it in the array, the query result set is an object and has only one piece of data, such as:

findByAttributes(array('username'=>'admin'));

or:

(10)

$admin=User::model()->findAllByAttributes($attributes,$condition,$params);

The result set returned If it is not empty, it is a two-dimensional array, and the result set of the first dimension of the array is an object.

(9)

// 如果查询条件很是复杂，就要使用CDbCriteria类
$criteria=new CDbCriteria;$criteria->select='title';$creteria->condition='postID=:postID';
$criteria->params=array(':postID'=>10);$post=Post::model()->find($criteria); // 不需要第二个参数
// 另一种更好的写法
$post=Post::model()->find( array(        'select'=>'title',        'condition'=>'postID=:postID',        'params'=>array(':postID'=>10)    ));

Query the number and determine whether the query has results

1,

$n=Post::model()->count($condition,$params);

This method is to query based on a condition How many records are there in a collection? Return an int number, such as:

count("username=:name",array(":name"=>$username));

2,

$n=Post::model()->countBySql($sql,$params);

This method is to query how many records there are in a collection based on the SQL statement , returns an int type number, such as:

countBySql("select * from admin where username=:name",array(':name'=>'admin'));

3,

$exists=Post::model()->exists($condition,$params);

This method is to query whether the array obtained has data based on a condition, and returns a true if there is data. Otherwise not found.

The above is a summary of the methods of database query data under the Yii framework. I believe everyone has a more detailed understanding of this. We also mentioned more related articles about the Yii framework earlier. You can pay attention to the PHP Chinese website.

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