Query optimizer decision to use index depends on data?

[Anan Tongprasith]

I have two tables which are exactly the same but have different set of data on them. I
wrote a query and used EXPLAIN to see how it would run on each table.
It turn out that the same query will use index on one table but not the other. So I delete
all data on the "bad" table (the one that won't use index) and copy data from the "good"
table over.
Now it says it will use index. Is this a bug?


Anan Tongprasith <atongprasith@stripped>