Question

I need data from 3 different tables:

1. Catergory table

2. Scoretable 1

3. Scoretable 2

What is now better for the performance?

1. Make 3 seperated SELECT Queries

2. Make 2 queries and connect scoretable 1 and 2 and make a normal select query for the categories

3. Connect all 3 queries in 1?

Number 2:

SELECT scoretable1.category, scoretable1.score, scoretable2.score
FROM scoretable1, scoretable2
WHERE scoretable1.consultant = scoretable2.consultant 
AND scoretable2.consultant = '14' 
AND scoretable1.category = scoretable2.category

Thank you very much!

P.S. The category table is very small so I could export it also as a cache file as a serialized array? (Maybe the best way for this table)

Answer 1

My guess would be that it is best to do it in one query. But i’m not absolutely sure. Maybe the query analyser can help you out here.