Yii2 数据操作之Query Builder

Query Builder

$rows = (new yiidbQuery())  
    ->select(['dyn_id', 'dyn_name'])  
    ->from('zs_dynasty')  
    ->where(['between','dyn_id', 1,30])  
    ->limit(10)  
    ->all();  
print_r($rows);  



use yiidbQuery;  
$query = (new Query())  
    ->from('user')  
    ->orderBy('id');

SELECT

$query->select('*')->  
    select('dyn_id as id, dynasty.dyn_name')->  
    $query->select(['dyn_id as id', "CONCAT(dyn_name,'a')"])->  
    $query->select('user_id')->distinct()->  

FORM

$query->from('user');  
$query->from(['public.user u', 'public.post p']);  
$query->from('public.user u, public.post p');  
$query->from(['u' => 'public.user', 'p' => 'public.post']);  


$subQuery = (new Query())->select('id')->from('user')-
    >where('status=1');  
// SELECT * FROM (SELECT `id` FROM `user` WHERE status=1) u   
$query->from(['u' => $subQuery]);  

 

WHERE

where('status=1')->  
where('status=:status', [':status' => $status])->  
where([  
    'status' => 10,  
    'type' => null,  
    'id' => [4, 8, 15],  
])->  
-------  
$userQuery = (new Query())->select('id')->from('user');  
// ...WHERE `id` IN (SELECT `id` FROM `user`)  
$query->...->where(['id' => $userQuery])->...  
--------  
['and', 'id=1', 'id=2'] //id=1 AND id=2  
['and', 'type=1', ['or', 'id=1', 'id=2']] //type=1 AND (id=1 OR id=2)  
['between', 'id', 1, 10] //id BETWEEN 1 AND 10  
['not between', 'id', 1, 10] //not id BETWEEN 1 AND 10  
['in', 'id', [1, 2, 3]] //id IN (1, 2, 3)  
['not in', 'id', [1, 2, 3]] //not id IN (1, 2, 3)  
['like', 'name', 'tester'] //name LIKE '%tester%'  
['like', 'name', ['test', 'sample']] //name LIKE '%test%' AND name LIKE '%sample%'  
['not like', 'name', ['or', 'test', 'sample']] //not name LIKE '%test%' OR not name LIKE '%sample%'  
['exists','id', $userQuery] //EXISTS (sub-query) | not exists  
['>', 'age', 10] //age>10  

ADD WHERE

$status = 10;  
$search = 'yii';  
$query->where(['status' => $status]);  
if (!empty($search)) {  
    $query->andWhere(['like', 'title', $search]);  
}  
//WHERE (`status` = 10) AND (`title` LIKE '%yii%')  
//andWhere() or orWhere()  

FILTER WHERE

$query->filterWhere([  
    'username' => $username,  
    'email' => $email,  
]);  
//如果email为空,则 WHERE username=:username

 

ORDER BY

$query->orderBy([  
    'id' => SORT_ASC,  
    'name' => SORT_DESC,  
]);  
//orderBy , addOrderBy  

GROUP BY

$query->groupBy('id, status');  
$query->addGroupBy(['created_at', 'updated_at']);  

HAVING 

$query->having(['status' => $status]);  
//having,andHaving,orHaving  

LIMIT OR OFFSET

$query->limit(10);  
$query->offset(10);  

JOIN

• innerJoin()
• leftJoin()
• rightJoin()

$query->select(['user.name AS author', 'post.title as title'])  
    ->from('user')  
    ->leftJoin('post', 'post.user_id = user.id');  
$query->join('FULL OUTER JOIN', 'post', 'post.user_id = user.id');  
$query->leftJoin(['u' => $subQuery], 'u.id=author_id');  

UNION

 

$query = new Query();  
$query->select("id, category_id as type, name")->from('post')->limit(10);  
$anotherQuery = new Query();  
$anotherQuery->select('id, type, name')->from('user')->limit(10);  
$query->union($anotherQuery);  

QUERY METHODS

• all() //所有行列
• one() //第一行
• column() //第一列
• scalar() //第一行第一列
• exists() //是否有结果存在
• count() //记录数量
• sum($q), average($q), max($q), min($q) //$q 为字段或表达式

$count = (new yiidbQuery())  
    ->from('user')  
    ->where(['last_name' => 'Smith'])  
    ->count();  
//SELECT COUNT(*) FROM `user` WHERE `last_name`=:last_name  
  
  
$command = (new yiidbQuery())  
    ->select(['id', 'email'])  
    ->from('user')  
    ->where(['last_name' => 'Smith'])  
    ->limit(10)  
    ->createCommand();  
      
// show the SQL statement  
echo $command->sql;  
// show the parameters to be bound  
print_r($command->params);  
  
  
// returns all rows of the query result  
$rows = $command->queryAll();  

 

QUERY RESULTS

use yiidbQuery;  
$query = (new Query())  
    ->from('user')  
    ->indexBy('username');  
foreach ($query->batch() as $users) {  
    // $users is indexed by the "username" column  
}  
foreach ($query->each() as $username => $user) {  
}  

INDEXING

 

use yiidbQuery;  
$query = (new Query())  
    ->from('user')  
    ->orderBy('id');  
foreach ($query->batch() as $users) {  
    // batch( $batchSize = 100, $db = null )  
    // 一个批次取100行  
}  
foreach ($query->each() as $user) {  
    // 一行一行取  
}