Putting an index on a Firebird field

Classic Servoy
1

With IB Manager by EMS, when I attempt to put an index on a Firebird field in some tables I get the following error:

---------- STATEMENT ----------

CREATE INDEX IDX_ITEMS
ON ITEMS (ITEM2)

---------- ERROR MESSAGE ----------

fmCompile.quCompile:
This operation is not defined for system tables.
unsuccessful metadata update.
key size too big for index IDX_ITEMS.

What do they mean by “system tables”? What does “key size too big” mean? Some fields can be indexed with no problems. However, the message above often comes up when I attempt to index certain fields in certain tables. I do not see anything in their Help file that explains this error message.

When an index such as IDX_ITEMS is successfully created where is the index stored? Does it become part of the .GDB file that contains the table/field being indexed?

2

Likely the column ‘item2’ is to large to be indexed, checkout the firebird docs for specification of maximum lenght in an index.