Submitted by: @mrotteveel

Relate to JDBC94
Duplicates CORE2697

Using a query with the condition "? in (SELECT some_col FROM some_table)" results in an error -804 Data type unknown. This was suppossed to fixed by CORE2697 for version 3.0, but it appears this is not the case.

Synthetic reproduction script (see also JDBC94)
CREATE TABLE VALUE_TABLE
(
INT_COLUMN Integer NOT NULL,
PRIMARY KEY (INT_COLUMN)
);
COMMIT;
INSERT INTO VALUE_TABLE(INT_COLUMN) VALUES (1);
COMMIT;

set term #⁠;
EXECUTE BLOCK
AS
DECLARE charResult CHAR(1);
BEGIN
EXECUTE STATEMENT ('SELECT ''x'' FROM RDB$DATABASE WHERE ? IN (SELECT INT_COLUMN FROM VALUE_TABLE)') (1) INTO charResult;
END#⁠
set term ;#⁠

Result:
Engine Code : 335544569
Engine Message :
Dynamic SQL Error
SQL error code = -804
Data type unknown

As stated in CORE2697 this could be rewritten to use EXISTS, but sometimes that is not an option if the query is generated.

====== Test Details ======

See test for CORE2697