Question

I have a data structure type question that I don’t really know the answer too. Essentially I have four permission controls (isSecret, canEdit, isActive and hasPage) that I need to store in a for a number of different tables.

I have two solutions in mind, but I’m not sure which is the best performance wise:

1. Store each permission as a separate row on each table. To me this seems to be the fastest way to access the data when querying, but because PHP will handle permissions 90% of the time, it seems inefficient.

2. Have a single permissions column where the permission name (sec,edt,act,has) is stored as a comma separated string. This gives me flexibly in the future to introduce new/different permissions, looks neat in my database and is easy to use in both PHP and mySQL (I can use the IN lookup for queries and explode the string and work with it as an array in PHP). This column would be a varchar of 40 characters, allowing to me store up to 10 different permissions (3 letters and a comma)

Option 2 was my preferred solution until I realised that the IN command might be resource intensive. I thought it might take a performance hit using an IN command on every row in my table trying to look for inactive pages to filter out. To solve this, I could just fetch every single row in my column, and then filter the rows out with PHP, but again, I’m not sure how effective this will be.

Ideally I think in my solution sub-columns would be the best solution (a main permissions column and under this 4 sub-columns for each of my permissions) that could then be queried easily (ie. where permission.canEdit = 1)

Results will eventually be cached using memcache (when I am able to figure out how to use it and an effective method for clearing it), but I don’t want to have to rely on this.

Answer 1

I think SETs would be what you need