Beginning Microsoft SQL Server 2008 ... - S3 Tech Training

Chapter 12: Stored Procedures
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checking works when it works, and how it doesn’t when it doesn’t (in particular, when inline does not
work, but TRY/CATCH would).
Let’s start with the referential integrity example we did earlier in this chapter:
USE AdventureWorks2008;
GO
INSERT INTO Person.BusinessEntityContact
(BusinessEntityID
,PersonID
,ContactTypeID)
VALUES(0,0,1);
You may recall this got us a simple 547 error. This is one of those that are trappable. We could trap this in
a simple script, but let’s do it as a sproc since procedural stuff is supposedly what we’re working on
here.
USE AdventureWorks2008
GO
CREATE PROC spInsertValidatedBusinessEntityContact
@BusinessEntityID int,
@PersonID int,
@ContactTypeID int
AS
BEGIN
END
DECLARE @Error int;
INSERT INTO Person.BusinessEntityContact
(BusinessEntityID
,PersonID
,ContactTypeID)
VALUES
(@BusinessEntityID, @PersonID, @ContactTypeID);
SET @Error = @@ERROR;
IF @Error = 0
PRINT ‘New Record Inserted’;
ELSE
BEGIN
IF @Error = 547 -- Foreign Key violation. Tell them about it.
PRINT ‘At least one provided parameter was not found. Correct and retry’;
ELSE -- something unknown
PRINT ‘Unknown error occurred. Please contact your system admin’;
END
Now try executing this with values that work:
EXEC spInsertValidatedBusinessEntityContact 1, 1, 11;