Firebird 2.1 Language Reference Update

External functions (UDFs)
DECLARE EXTERNAL FUNCTION i64Round
NUMERIC(18,4) BY DESCRIPTOR, NUMERIC(18,4) BY DESCRIPTOR
RETURNS PARAMETER 2
ENTRY_POINT 'round' MODULE_NAME 'fbudf'
In Firebird 1.5, the entry point has been renamed to fbround:
DECLARE EXTERNAL FUNCTION Round
INT BY DESCRIPTOR, INT BY DESCRIPTOR
RETURNS PARAMETER 2
ENTRY_POINT 'fbround' MODULE_NAME 'fbudf'
DECLARE EXTERNAL FUNCTION i64Round
NUMERIC(18,4) BY DESCRIPTOR, NUMERIC(18,4) BY DESCRIPTOR
RETURNS PARAMETER 2
ENTRY_POINT 'fbround' MODULE_NAME 'fbudf'
If you move an existing database from Firebird 1.0.x to 1.5 or higher, drop any existing *round and
*truncate declarations and declare them anew, using the updated entry point names. From Firebird
2.0 onward you can also perform this update with ALTER EXTERNAL FUNCTION.
Library: ib_udf
Added in: 1.5
Changed in: 1.5.2, 2.0
Better alternative: Internal function RPAD()
rpad
Description: Returns the input string right-padded with padchars until endlength is reached.
Result type: VARCHAR(n)
Syntax:
rpad (str, endlength, padchar)
Declaration:
DECLARE EXTERNAL FUNCTION rpad
CSTRING(255) NULL, INTEGER, CSTRING(1) NULL
RETURNS CSTRING(255) FREE_IT
ENTRY_POINT 'IB_UDF_rpad' MODULE_NAME 'ib_udf'
The above declaration is from the file ib_udf2.sql. The NULLs after the CSTRING arguments
are an optional addition that became available in Firebird 2. If an argument is declared with the NULL
keyword, the engine will pass a NULL argument value unchanged to the function. This leads to a NULL
result, which is correct. Without the NULL keyword (your only option in pre-2.0 versions), NULLs
are passed to the function as empty strings and the result is a string with endlengh padchars (if str
is NULL) or a copy of str itself (if padchar is NULL).
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