> Is anywhere a statistic about usage of tables

No.

> So I can decide which fields to index

You have to check your queries for that.

> Is anywhere specific documentation about FireBird system tables, DB

optimizations, right fields indexing etc?

Martijn Tonies
Database Workbench - tool for InterBase, Firebird, MySQL, NexusDB, Oracle &
MS SQL Server
Upscene Productions
http://www.upscene.com
My thoughts:
http://blog.upscene.com/martijn/
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