index choose and analyze table

[Jens Schanz]

Hi,

i've a MySQL-5.0.1 server and a database which data is sotred in an InnoDB-Tablespace.
Through the whole day, i've a lot of inserts and updates. Nightly I run a report which 5 or 6 selects.
After a reboot, the explain shows me, that for all questions an index will be used. If i'll wait a few hours the optimizer choose a full table scan instead the use of an index. After an anaylze table, the index will be used again.
Is there any possibility to watch a value, if the query would use an index or not (I think the statistics are optimized for the index and update statements)?

Brgds,
Jens