防止在mysql中返回重复的行

Question

我在php中完成了三个餐厅搜索表.搜索可以选择按复选框状态按多种类型对其进行过滤.某些餐馆可能属于多种类型,并且在type_stack表中会有多个条目.

Table1 - **restaurant**
------+----------+----------
  id  +   name   +   place
------+----------+----------
   1      rest1       ny
   2      rest2       la
   3      rest3       ph
   4      rest4       mlp


Table2 - **r_type**
------+----------+----------
  id  +   name   +   code
------+----------+----------
   1      type1       0
   2      type2       1
   3      type3       2
   4      type4       3


Table3 - **type_stack**
------+----------+----------
  id  + rest_id  +   type
------+----------+----------
   1      2          2
   2      4          1
   3      1          2

我想让所有符合用户类型的餐厅都选中.但问题是1次多次到同一家餐馆.我只希望一次显示一行.

这是我的查询

SELECT restaurant.name, restaurant.place FROM restaurant, type_stack WHERE restaurant.id = type_stack.rest_id AND type_stack.type = '0' AND type_stack.type = '1' AND type_stack.type = '2' LIMIT 0 , 30

查询是基于复选框状态进行的!在这种情况下,选择类型0,1和2.

Answer 1

将您的陈述更改为(您需要DISTINCT):

SELECT DISTINCT restaurant.name, restaurant.place FROM restaurant, type_stack WHERE restaurant.id = type_stack.rest_id AND type_stack.type = '0' AND type_stack.type = '1' AND type_stack.type = '2' LIMIT 0 , 30