ThinkPHP query statements and usage of related queries
This article mainly introduces the usage of ThinkPHP query statements and related queries, and common query methods in the form of examples, including techniques such as arrays as query conditions and object methods for querying. Friends in need can refer to it
The examples in this article describe the usage of ThinkPHP query statements and related queries. Share it with everyone for your reference. The details are as follows:
In the thinkphp framework page, we can directly spell sql query statements to implement database query read and write operations. Here is an example to illustrate this.
In addition to string query conditions for ordinary queries, array and object query conditions are very commonly used, and these are necessary for basic queries.
1. Use arrays as query conditions
$User = M("User"); //实例化User对象 $condition['name'] = 'thinkphp'; // 把查询条件传入查询方法 $User->where($condition)->select();
2. Use object mode to query. You can use any object. Here we take the stdClass built-in object as an example.
$User = M("User"); // 实例化User对象 // 定义查询条件 $condition = new stdClass(); $condition->name = 'thinkphp'; // 查询name的值为thinkphp的记录 $User->where($condition)->select(); // 上面的查询条件等同于 where('name="thinkphp"') 使用对象方式查询和使用数组查询的效果是相同的,并且是可 带where条件的普通查询
1. String form
$user=M('user'); $list=$user->where('id>5 and id<9')->select(); $list=$user->where($data)->select();
2. Array format
$user=M('user'); $list=$user->where(array('username'=>'www.jb51.net'))->select(); $list=$user->where($data)->select();
3. Object format
$user=M('user'); $a=new stdClass(); $a->username='www.jb51.net; $list=$user->where($a)->select();
Associative query between two tables:
$M_shopping = M('Shops'); $M_product = M('Product'); $list_shops = $M_shopping->join('as shops left join hr_product as product on shops.product_id = product.p_id') ->field('product.p_id,product.p_name,shops.product_amount,shops.product_id') ->where("shops.user_cookie='".$_COOKIE['hr_think_userid']."'") ->group('shops.id') ->select();
Interval query
$user=M('user'); $data['id']=array(array('gt',20),array('lt',23),'and'); $list=$user->where($data)->select();
Combined query
$user=M('user'); $data['username']='pengyanjie'; $data['password']=array('eq','pengyanjie'); $data['id']=array('lt',30); $data['_logic']='or'; $list=$user->where($data)->select(); dump($list);
Compound query
$user=M('user'); $data['username']=array('eq','pengyanjie'); $data['password']=array('like','p%'); $data['_logic']='or'; $where['_complex']=$where; $where['id']=array('lt',30); $list=$user->where($data)->select();
Associated query of three data tables
$M_shopping = M('Shops'); $M_product = M('Product'); $M_proimg = M('Product_image'); $list_shops = $M_shopping->join('as shops left join hr_product as product on shops.product_id = product.p_id left join hr_product_image as productimgon productimg.p_id = product.p_id')->fiel('productimg.pi_url,product.p_id,product.p_name,shops.product_amount,shops.product_id,product.am_id, product.p_procolor,product.p_price,product_amount*p_price as totalone')->where("shops.user_cookie='".$_COOKIE['hr_think_userid']."'") ->group('shops.id')->select();
Query conditions of the data table
① The following is a direct query The conditions are placed in where, which makes it easier to write the conditions
$m_test = M("Product"); $productmeaage = $m_test->where("p_id='$proid'")->select();
② In addition to the above method, there is also an array method
$M_product = M('Product'); $map['pid'] = $proid; $p_result = $M_product->where($map)->select();
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