Using LIKE on numerical indexes
I've got a table with 250,000 entries and a primary INT field. I'm in a situation where I need to find all the ids what start with a given set of prefix. So I tried a like:
But it does turn out to be pretty slow, and apparently doesn't use the index, presumably because a numerical index is useless for a string comparison function.
WHERE id LIKE "123%"
My next attempt was to check for a set of number ranges that are covered by the given prefix
This method seems to be faster and uses the index. But it's a bit messier. Any other approach I could try?
OR id between 1230 AND 1239
OR id between 12300 AND 12399
OR id between 123000 AND 123999
OR id between 1230000 AND 1239999
#or however high up you want to check.