Hi, This has nothing to do with FDB. Parameters (?) are implemented by Firebird engine itself, FDB just supports it. So you should ask such question in Firebird-support list, or check out https://stackoverflow.com/questions/37348807/data-type-unknown-in-case-expression-with-only-parameters-as-values
regards Pavel Cisar IBPhoenix Dne 15.4.2018 v 03:03 maxiroba...@gmail.com [firebird-python] napsal(a): > Hi, > > I have the next sql command > > sql = 'SELECT > "EXPRESSIONS_COMPANY"."ID", > "EXPRESSIONS_COMPANY"."NAME", > "EXPRESSIONS_COMPANY"."NUM_EMPLOYEES", > "EXPRESSIONS_COMPANY"."NUM_CHAIRS", > "EXPRESSIONS_COMPANY"."CEO_ID", > "EXPRESSIONS_COMPANY"."POINT_OF_CONTACT_ID", > ? AS "FOO" > FROM "EXPRESSIONS_COMPANY" > WHERE ? = ? > ORDER BY "EXPRESSIONS_COMPANY"."NAME" ASC' > > Running this sql > cur.execute(sql, ['value', 'value', 'value']) > > Raise an exception: > SQL error code = -804 - Data type unknown' > > Of course, fdb doesn't replace params from entire sql command, just from > where clause. > > Is this behavior the standard according to python db-api ? > Is there another approach to accomplish using fdb without make a string > replacement ? > > > Regards > Maxi > > > > > > > > > > > >