When I try to use the show lpad 2 times in the same sql does error give me, as solving this?

Starting transaction...
Preparing query: SELECT a.CODIGO, lpad(CAST(a.CUENTAUSD AS VARCHAR(4)),4, '0') AS CUENTAUSD, lpad(a.SUBCTAUSD, 3, '0') AS SUBCTAUSD
FROM ALMINV a ORDER BY a.CODIGO

Error: *** IBPP::SQLException ***
Context: Statement::Prepare( SELECT a.CODIGO, lpad(CAST(a.CUENTAUSD AS VARCHAR(4)),4, '0') AS CUENTAUSD, lpad(a.SUBCTAUSD, 3, '0') AS SUBCTAUSD
FROM ALMINV a ORDER BY a.CODIGO)
Message: isc_dsql_prepare failed

SQL Message : -204
Undefined name

Engine Code : 335544569
Engine Message :
Dynamic SQL Error
SQL error code = -204
Implementation limit exceeded
block size exceeds implementation restriction

WI-V2.1.3.18185 Firebird 2.1
WI-V0.9.3.1870 FlameRobin

Thanks
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¦¦ ISMAEL ¦¦
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