Best table design for application configuration or application option settings?

Question

I need to store a series of configuration values in a database. A couple ways I thought of to store them are: a table with 2 colums(name,value) and a row for each pair, or

Answer 1

The first issue you should consider is this: stop thinking about the efficiency of retrieving the information. first and foremost, figure out how to effectively and correctly model the data and then (and only then) figure out how to do it efficiently.

So it depends on the nature of the config data you're storing. If separate (name,value) pairs are basically unrelated then store it as one per row. If they are related then you may want to consider a scheme that has multiple columns.

What do I mean by related? Consider some cache config. Each cache has several attributes:

• eviction policy;
• expiry time;
• maximum size.

Assume each cache has a name. You could store this data as three rows:

• _EVICTION
• _EXPIRY
• _MAX_SIZE

but this data is related and you may often need to retrieve them all at once. In that case it may make sense to have a cache_config table with five columns: id, name, eviction, expiry, max_size.

That's what I mean by related data.