条件查询
cond)->all();
$cond就是我们所谓的条件，条件的写法也根据查询数据的不同存在差异，那么如何用yii2的方式来写查询条件呢？
【简单条件】
<?php
// SQL: (type = 1) AND (status = 2).
$cond = ['type' => 1, 'status' => 2]
// SQL:(id IN (1, 2, 3)) AND (status = 2)
$cond = ['id' => [1, 2, 3], 'status' => 2]
//SQL:status IS NULL
$cond = ['status' => null]
【and】:将不同的条件组合在一起，用法举例：
//SQL:`id=1 AND id=2`
$cond = ['and', 'id=1', 'id=2']
//SQL:`type=1 AND (id=1 OR id=2)`
$cond = ['and', 'type=1', ['or', 'id=1', 'id=2']]
//SQL:`type=1 AND (id=1 OR id=2)` //此写法'='可以换成其他操作符，例：in like != >=等
$cond = [
'and',
['=', 'type', 1],
[
'or',
['=', 'id', '1'],
['=', 'id', '2'],
]
]
【or】:
//SQL:`(type IN (7, 8, 9) OR (id IN (1, 2, 3)))`
$cond = ['or', ['type' => [7, 8, 9]], ['id' => [1, 2, 3]]
【not】
//SQL:`NOT (attribute IS NULL)`
$cond = ['not', ['attribute' => null]]
【between】: not between 用法相同
//SQL:`id BETWEEN 1 AND 10`
$cond = ['between', 'id', 1, 10]
【in】: not in 用法类似
//SQL:`id IN (1, 2, 3)`
$cond = ['in', 'id', [1, 2, 3]] or $cond = ['id'=>[1, 2, 3]]
//IN条件也适用于多字段
$cond = ['in', ['id', 'name'], [['id' => 1, 'name' => 'foo'], ['id' => 2, 'name' => 'bar']]]
//也适用于内嵌sql语句
$cond = ['in', 'user_id', (new Query())->select('id')->from('users')->where(['active' => 1])]
【like】
//SQL:`name LIKE '%tester%'`
$cond = ['like', 'name', 'tester']
//SQL:`name LIKE '%test%' AND name LIKE '%sample%'`
$cond = ['like', 'name', ['test', 'sample']]
//SQL:`name LIKE '%tester'`
$cond = ['like', 'name', '%tester', false]
【exists】: not exists用法类似
//SQL:EXISTS (SELECT "id" FROM "users" WHERE "active"=1)
$cond = ['exists', (new Query())->select('id')->from('users')->where(['active' => 1])]
【此外，您可以指定任意运算符如下】
//SQL:`id >= 10`
$cond = ['>=', 'id', 10]
//SQL:`id != 10`
$cond = ['!=', 'id', 10]
注：转载地址：https://blog.csdn.net/m15712884682/article/details/52979306
