public function demo()

{

$res = null;

//insert数据插入

//$user=array('username'=>'joy','password'=>'123456','age'=>23);

//$res = DB::table('users')->insert($user);

/*

数据查询

$res = DB::table('users')->where('username','joy')->get();

$res = DB::select('SELECT * FROM users WHERE username="joy"');

*/

/*

更新数据

$res =DB::update('UPDATE users SET age=25 WHERE username="joy"');

$res =DB::table('users')->where('username','joy')->update(array('age' =>23));

*/

/*

删除数据

$res = DB::delete('DELETE FROM users WHERE username="joy"');

$res = DB::table('users')->where('username','joy')->delete();

*/

/*

字段添加

$res = DB::statement('ALTER TABLE users ADD sex tinyint(1) not null default 0');

*/

/*事务

DB::transaction(function(){

$user=array(xxxx);

DB::table('user')->insert($user);

DB.....

});

*/

/*结果查询器

$res = DB::table('users')->where('username','Qing')->pluck('age');//去特定字段值

$res = DB::table('users')->lists('age');//特殊字段list值

$res = DB::table('users')->select(array('id','username'))->get();多个特殊字段查询

$res = DB::table('users')->where('id','>',1)->get();

$res = DB::table('users')->where('id',1)->get();

$res = DB::table('users')->whereId(1)->get();

//user_age->whereUserAge

$res = DB::table('users')->where('id','<',3)->where('username','Qing')->get();

$res = DB::table('users')->where('id','>',3)->orWhere('username','Qing')->get();

//username = Qing and (age>13 or sex=0)

$res = DB::table('users')->where('username','Qing')->where(function($query){

$query->where('age','>',13)->orWhere('sex',0);

})->get();

$res = DB::table('users')->whereBetween('age',array(0,15))->get();

$res = DB::table('users')->whereNotBetween('age',array(0,15))->get();

$res = DB::table('users')->whereIn('age',array(23,30))->get();

$res = DB::table('users')->whereNot In('age',array(23,30))->get();

*/

//$res = DB::table('users')->groupBy('sex')->orderBy('id','DESC')->having('sex','=',0)->get();

//$res = DB::table('users')->limit(2,3)->get();

//$res = DB::table('users')->skip(2)->take(1)->get();

//$res = DB::table('posts')->join('users','posts.user_id','=','users.id')->get();

// $res = DB::table('posts')->join('users',function($query){

// $query->on('posts.user_id','=','users.id');//->On(...);

// })->get();

/*

嵌套查询

$res = DB::table('users')->where(function($query){

if(Input::get('status')){

$query->whereStatus(Input::get('status'));

}

if(Input::get('source')){

$query->whereSource(Input::get('source'));

}

})->get();

*/

/*

$res = DB::table('users')->whereExists(function($query){

$query->select('*')->from('posts')->whereRaw(DB::raw('users.id = posts.user_id'));

})->get();

*/

//$res = DB::table('users')->where('id','>','2')->count();

// $res = DB::table('posts')->where('id',6)->decrement('view_count',5);

// $res=DB::table('posts')->truncate();

//$res=DB::table('users')->where('id','>',2)->remember(0.2)->get();

echo "<pre>";

print_r($res);

echo "</pre>";

return 'ok';

}