数据库中的标签系统实现

Current Structure

table [Tags]

TagID
TagName

table [Stores]

StoreID
StoreName
StoreCategory
StoreTagID

this will only make the store have one tag , how can I implement it to allow more than one tag I made tags group but not working also parsing but its usless like tagid:tagname,tagid:tagname...... for the same row but not efficient.

A common way to do this sort of thing is to create a third table e.g.

table [Store_Tags]

StoreID
TagID

Getting the tags for the Store then requires a join against Store_Tags to Tags e.g.

SELECT TagName FROM Tags INNER JOIN Store_Tags USING(TagID) WHERE StoreID = ?

An alternate approach would be to avoid using the Tag table and put the TagName directly in the Store_Tags table, it really depends how you intend to use the data.

StackOverflow has all tags in separated DB table

Posts
  PostId
PostTags
  PostId
  TagId
Tgas
  TagId
  TagName

you can do similar