How to recreate the index on a Firebird table?
Recreating the index:
ALTER INDEX indexName INACTIVE.
ALTER INDEX indexName ACT1VE
Please note that it does not work for indices automatically created by the system like the ones for primary key or foreign key. You might want to drop and recreate the constraints in such case.
To recalculate the index statistics (which is enough for most cases), use:
SET STATISTICS INDEX indexName;