sql - Capturing multiple error messages from a single statement inside TRY CATCH

Question

I am running a batch of statements on several columns and tables and want to retrieve information on what errors occur.

The statement is a type change (varchar to nvarchar) and when it fails, it seems to return 2 errors.

Msg 5074, Level 16, State 1, Line 1 The object 'DF_XXX_YYY' is dependent on column 'YYY'.

Msg 4922, Level 16, State 9, Line 1 ALTER TABLE ALTER COLUMN Description failed because one or more objects access this column.

However, when I wrap it in a TRY/CATCH block, and select ERROR_MESSAGE(), it only returns the second error:

ALTER TABLE ALTER COLUMN Description failed because one or more objects access this column.

Ideally I would have it return the first message, as this is much more informative.

The exact SQL statement is:

begin try
    alter table XXX
    alter column YYY
    nvarchar(200)
end try
begin catch
    select ERROR_MESSAGE(), ERROR_LINE(), ERROR_NUMBER(), ERROR_PROCEDURE(), ERROR_SEVERITY(), ERROR_STATE()
end catch

Does anyone know how I can retrieve the more informative message? (@@ERROR also returns the second error)

Answer 1

Depending on your needs and the permissions of the account that you are running this script under you may be able to use DBCC OUTPUTBUFFER(@@spid).

I came across this idea when reading Erland Sommarskog's Error Handling article. He links to a procedure spGET_ErrorMessage.

Unfortunately this didn't quite work in my test script on SQL Server 2008 though so I'm not sure if the buffer format has changed but it might get there with a bit of tweaking!

CREATE TABLE #foo
(
c INT DEFAULT(0)
)
ALTER TABLE #foo ALTER COLUMN c VARCHAR(10)

GO
EXEC spGET_LastErrorMessage

Actual Output

Msg 5074, Level 16, State 1, Line 2
The object 'DF__#foo___________c__6DCC4D03' is dependent on column 'c'.

    Msg 4922, Level 16, State 9, Line 2
    ALTER TABLE ALTER COLUMN c failed because one or more objects access this column.

Claimed Output

errNumber            errState    errLevel    errMessage                                                                               errInstance                                                                                                                     errProcedure    errLine
-------------------- ----------- ----------- ---------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------------- --------------- -----------
5074                 1           16          The object 'DF__#foo___________c__6DCC4D03' is dependent on column 'c'.                  MARTINHP                                                                                                                        NULL            2
4922                 9           16          The object 'DF__#foo___________c__6DCC4D03' is dependent on column 'c'.ALTER TABL        MARTINHP???吀?刀??伀?唀?一?挀?昀愀椀氀攀搀?戀攀挀愀甀猀攀?漀渀攀?漀爀?洀漀爀攀?漀戀樀攀挀琀猀?愀挀挀攀猀猀?琀栀椀         NULL            117