Re: CASE Statement
From: Serge Rielau <srielau_at_ca.ibm.com>
Date: Wed, 25 Jun 2008 07:45:54 -0400
Message-ID: <6cepfhF3fu2v6U1@mid.individual.net>
Date: Wed, 25 Jun 2008 07:45:54 -0400
Message-ID: <6cepfhF3fu2v6U1@mid.individual.net>
Nit:
SQL knows two (aside from searched vs. simple) different forms of CASE
constructs:
Statement and expression
The CASE STATEMENT is a flavor of IF THEN ELSE procedural logic. I.e. it belongs into the world of SQL/PSM (or PL/SQL in the case of Oracle). The CASE EXPRESSION is a functional construct and belongs into the world of SQL queries.
Statement (in SQL/PSM notation):
CASE
WHEN a > b THEN
INSERT INTO T VALUES (1);
WHEN b < a THEN
INSERT INTO T VALUES (2);
END CASE;
Expression:
INSERT INTO T VALUES (CASE WHEN a > b THEN 1 WHEN b < a THEN 2 END);
So it pays to be precise on the wording here to clarify what's being looked for.
Cheers
Serge
-- Serge Rielau DB2 Solutions Development IBM Toronto LabReceived on Wed Jun 25 2008 - 06:45:54 CDT