Yii: 查询符合条件的记录个数

1: 通过find方法

$res = findAll(...); (or findAllByAttributes)

$num = count($res)

2: 通过count方法

$res1 = countByAttributes(...);

$res2 = countBySql(...);

3: 通过query方法

$sql = "SELECT COUNT(*) as clients FROM client_table";
$command = Yii::app()->db->createCommand($sql);
$results = $command->queryAll();
$numClients = (int)$results[0]["clients"];

通过queryScalar可以让上面的语句更简单:

$sql = "SELECT COUNT(*) FROM client_table";
$numClients = Yii::app()->db->createCommand($sql)->queryScalar();