Firebird does not support more than 1499 elements in an IN clause
list. Is there any effort to raise this limit? I understand that we
must try to avoid cases where the number of elements in an IN list is
big, but there are circumstances such as DSQL (e.g. using DSQL in a
c++ code) where we are faced with this limit. For example, an
application receives 2000 identifiers and it must perform a query to
get records identified by these identifiers.

So, what is the recommended workaround for this limit (e.g. in terms
of performance)?

Alternatives:

A) Store IDs into a temporary table and use that table in an IN
clause.

SELECT *
FROM <table>
WHERE ID IN ( SELECT ID FROM <temporary_table> )

B) Execute multiple queries, each having maximally 1499 elements in
an IN list, and then combine the results.

SELECT *
FROM <table>
WHERE ID IN ( 1, 2, 3, ..., 1499 )

combined with

SELECT *
FROM <table>
WHERE ID IN ( 1500, 1501, 1502, ..., 2998 )

Other solutions?

Thanks in advance.

Timo