Commented by: @aafemt

Why? DDL is not a time-critical operations.

Commented by: Attila Molnár (e_pluribus_unum)

Everything is time critical! We are planning to run hunderds of small databases, and database upgrade have to be fast (SaaS with very high availability).

It's impossible to put an index to a rdb$ref_constraints?

Commented by: @aafemt

It is most likely pointless. You can test it yourself: create desired index and compare speed of operations before and after that.

Commented by: Attila Molnár (e_pluribus_unum)

Currently it has only 1 index on field RDB$CONSTRAINT_NAME.
Putting an index to RDB$CONST_NAME_UQ does not help. The problem is deeper in the engine.

Commented by: @dyemanov

Have you reconnected (disconnected everybody in the case of SS) before testing with a newly created index?

Commented by: Attila Molnár (e_pluribus_unum)

Putting an index to RDB$CONST_NAME_UQ, and reconnecting works fine.
Please put a system index to it.

Thank you.

Commented by: @reevespaul

Have you done any benchmarking on this?

Unless you have a very large table using a index will more than likely be slower than a direct table scan.

Commented by: Attila Molnár (e_pluribus_unum)

In the near future (end of the year) the record count of rdb$ref_constraints estimated over 1000. (in far future up to 5000 is possible)
Readind 1 record directly through index is faster than x K record natural scan.

This is still an issue (Tested with FB30 and FB40)