如何将复选框值存储到mysql字段进行搜索？

Question

I want to storage checkbox valus to a field.

html like this

two value selected

<input type="checkbox" value="1">invest_type1
<input type="checkbox" value="2" checked>invest_type2
<input type="checkbox" value="3" checked>invest_type3
<!-- more, but less than 20-->

mysql table dict

id
project_name
invest_types   // how to save?
// other fields

Demand

multiple select

exp. User select "invest1" and "invest2",then how to fetch that row?

Plans

1. use bit method to storage.

   invest_type2 is 2 , pow(2,2) => 4

   invest_type2 is 3 , pow(2,3) => 8

   4+8=12,when select use invest_types & (invest_type1's pow + invest_type2's pow)

2. add table to relate

   add table to storage invest_types with every project.

   use join and distinct when use search.

Problem & Help

• Which plan is the best?
• What about efficiency of plan1?

Answer 1

Which plan is the best?

It depends on your ER model. If you only need to store and search trough those preferences I will go with plan1. Instead if you need to associate those preferences to multiple related entities I will go with plan2

What about efficiency of plan1?

Your proposed plan1 can be very efficient, in fact you can use php bitwise functions (http://php.net/manual/en/language.operators.bitwise.php) to create the values you will save into the db and then use the mysql bitwise functions to retrieve and search on it (http://dev.mysql.com/doc/refman/5.7/en/bit-functions.html)