Telling MySQL Which Index to Use

**Disclamer: ** I'm sure MySQL database administrators will tell me that this is SUPER wrong because I should always let the database engine pick what indexes to use but this feature exists for a reason. That being said I'm NOT a database administrator I'm just a programmer that plays one on TV.

The other day we ran into an issue where a page would take about 60 seconds to rendering and the problem was tracked back to a single query. Lets say it looked like something like this:

SELECT * 
FROM Table1
INNER JOIN Table2 ON Table2.id = Table1.Table2Id 
WHERE Table2.column = 'true';

When I ran explain on the query I got the following:

I've never seen it use intersection before and I had a index set for all the columns I was using. In MySQL you can force it to use an index:

SELECT * 
FROM column
INNER JOIN Table2 USE INDEX (column_idx) ON Table2.id = Table1.Table2Id 
WHERE Table2.column = 'true';

This simple change took the query from 60 seconds to 0.5.