Обсуждение: message for constraint
Hi, From time to time people ask me if there is a way to "customize" messages for constraints so they could be more informative to the user... Imagine something like: create table foo (fld int4 check (fld > 0)); message for constraint foo_fld_check on foo is 'fld field must contain possitive numbers only.'; so i can let this message go directly to my users, and they can respond without knowing waht a check constraint is... we can use the pg_description catalog with a column added to indicate if it is a comment or a message for constraint... what do you think, it's worth the effort? -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)
Jaime Casanova wrote: > From time to time people ask me if there is a way to "customize" > messages for constraints so they could be more informative to the > user... What about this? => create table foo (fld int4 constraint "fld must contain positive numbers" check (fld > 0)); CREATE TABLE => insert into foo values (-5); ERROR: new row for relation "foo" violates check constraint "fld must contain positive numbers" -- Peter Eisentraut http://developer.postgresql.org/~petere/
On 1/14/06, Peter Eisentraut <peter_e@gmx.net> wrote: > Jaime Casanova wrote: > > From time to time people ask me if there is a way to "customize" > > messages for constraints so they could be more informative to the > > user... > > What about this? > > => create table foo (fld int4 constraint "fld must contain positive numbers" check (fld > 0)); > CREATE TABLE > => insert into foo values (-5); > ERROR: new row for relation "foo" violates check constraint "fld must contain positive numbers" > > -- > Peter Eisentraut > http://developer.postgresql.org/~petere/ > ok, i didn't know you can use such names... -- regards, Jaime Casanova (DBA: DataBase Aniquilator ;)