Searching w/ Comma Delimited Field

[evolutionm]

I'm trying to search a table based on categories. I currently have categories stored in a mediumtext field with their ids separated by commas.

Ex. categories = '01,02,03'

I have a search box that allows a person to select the categories to filter by (using checkboxes). Once those categories are selected, I need to run a query to see which users have at least one of those categories in their categories field.

The issue I have is that I need to do this within the query and the categories field contains multiple values instead of just one. For each category that was checked in the form, I need to see if that id exists within the categories field.

I tried placing the id first and then comparing it to the field:

Ex. '$id' IN (categories)

That didn't seem to work although it didn't give any MySQL errors. I thought that maybe it didn't recognize that categories was actually the field vs a string.

Is there a special function I could use to accomplish what I'm looking to do?

Mark

[ColdScripts.com]

if all the categories ids are 2 digits (00-99) this could work : categories LIKE '%$id%'

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Mario

[r937]

your basic problem is the design of the table

any time you have a comma-delimited list inside a column, you're going to end up with inefficient sql that won't scale

if someone chooses categories 4, 9, and 37 from the checkboxes, you have to actually do three queries (inside a loop)

and each one will do a table scan

i advise you to redesign into a proper many-to-many relationship

then you can use table indexes, and your queries will not only be incredibly simple, but extremely efficient

[stereofrog]

evolutionm

The function you're looking for is FIND_IN_SET(). I’d better listen to Rudy's advice though.