視圖查詢(xun)可以實現不(bu)依賴數據(ju)庫視圖的多表查詢(xun)，并不(bu)需要數據(ju)庫支持視圖，例如：

Db::view('User','id,name')
    ->view('Profile','truename,phone,email','Profile.user_id=User.id')
    ->view('Score','score','Score.user_id=Profile.id')
    ->where('score','>',80)
    ->select();

生成的(de)SQL語句類似于：

SELECT User.id,User.name,Profile.truename,Profile.phone,Profile.email,Score.score FROM think_user User INNER JOIN think_profile Profile ON Profile.user_id=User.id INNER JOIN think_socre Score ON Score.user_id=Profile.id WHERE Score.score > 80

注意，視圖查詢無需調用table和join方法，并且在調用where和order方法的時(shi)候只需(xu)要使用字段名(ming)(ming)而不需(xu)要加表(biao)名(ming)(ming)。

默認使(shi)用INNER join查詢(xun)，如果需要更改(gai)，可以(yi)使(shi)用：

Db::view('User','id,name')
    ->view('Profile','truename,phone,email','Profile.user_id=User.id','LEFT')
    ->view('Score','score','Score.user_id=Profile.id','RIGHT')
    ->where('score','>',80)
    ->select();

生成(cheng)的SQL語句類似于：

SELECT User.id,User.name,Profile.truename,Profile.phone,Profile.email,Score.score FROM think_user User LEFT JOIN think_profile Profile ON Profile.user_id=User.id RIGHT JOIN think_socre Score ON Score.user_id=Profile.id WHERE Score.score > 80

可以使(shi)用(yong)別(bie)名：

Db::view('User',['id'=>'uid','name'=>'account'])
    ->view('Profile','truename,phone,email','Profile.user_id=User.id')
    ->view('Score','score','Score.user_id=Profile.id')
    ->where('score','>',80)
    ->select();

生成(cheng)的SQL語句(ju)變(bian)成(cheng)：

SELECT User.id AS uid,User.name AS account,Profile.truename,Profile.phone,Profile.email,Score.score FROM think_user User INNER JOIN think_profile Profile ON Profile.user_id=User.id INNER JOIN think_socre Score ON Score.user_id=Profile.id WHERE Score.score > 80

可(ke)以使用數組的(de)方式定義表(biao)名(ming)以及別名(ming)，例(li)如：

Db::view(['think_user'=>'member'],['id'=>'uid','name'=>'account'])
    ->view('Profile','truename,phone,email','Profile.user_id=member.id')
    ->view('Score','score','Score.user_id=Profile.id')
    ->where('score','>',80)
    ->select();

生成的SQL語句變成：

SELECT member.id AS uid,member.name AS account,Profile.truename,Profile.phone,Profile.email,Score.score FROM think