Firebird 2.1 Language Reference Update
Firebird 2.1 Language Reference Update
Firebird 2.1 Language Reference Update
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CREATE DOMAIN<br />
Available in: DSQL, ESQL<br />
Context variables as defaults<br />
Changed in: IB<br />
DDL statements<br />
DOMAIN<br />
Description: Any context variable that is assignment-compatible to the new domain's datatype can be used as a<br />
default. This was already the case in InterBase 6, but the <strong>Language</strong> <strong>Reference</strong> only mentioned USER.<br />
Example:<br />
create domain DDate as<br />
date<br />
default current_date<br />
not null<br />
ALTER DOMAIN<br />
Available in: DSQL, ESQL<br />
Warning<br />
If you change a domain's definition, existing PSQL code using that domain may become invalid. If this happens,<br />
the system table field RDB$VALID_BLR will be set to 0 for any procedure or trigger whose code is no longer<br />
valid. If you have changed a domain, the following query will find the code modules that depend on it and<br />
report the state of RDB$VALID_BLR:<br />
select * from (<br />
select 'Procedure', rdb$procedure_name, rdb$valid_blr from rdb$procedures<br />
union<br />
select 'Trigger', rdb$trigger_name, rdb$valid_blr from rdb$triggers<br />
) (type, name, valid)<br />
where exists<br />
(select * from rdb$dependencies<br />
where rdb$dependent_name = name and rdb$depended_on_name = 'MYDOMAIN')<br />
/* Replace MYDOMAIN with the actual domain name. Use all-caps if the domain<br />
was created case-insensitively. Otherwise, use the exact capitalisation. */<br />
Unfortunately, not all PSQL invalidations will be reflected in the RDB$VALID_BLR field. It is therefore advisable<br />
to look at all the procedures and triggers reported by the above query, even those having a 1 in the<br />
“VALID” column.<br />
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