Question

I need a common select statement that returns a fixed value / row without the need of tables, which has to work with both Oracle & Sql Server.

eg for Oracle I know I can use:

select 'O' AS INDICATOR from DUAL;

But this won’t work on Sql Server.

Can this be done with the same SQL on both Oracle & SQL Server?

Answer 1

AFAIK, you’ll need different queries, unless you can find a table that exists both on the SQL Server and on the Oracle Server.

Oracle uses the DUAL table for dummy queries, while the syntax to just select a constant on SQL server is a bit simpler:

select 'O' as Indicator

will return a one-row recordset.

P.S. If you intend to write just standard SQL and have it work on both SQL Server and Oracle, note that there are lots and lots of differences, even if you do not use database-side code (stored procedures and functions).

Off the top of my head, some things that are different:

• Case statement syntax
• NVL vs IsNull
• Null sorting behaviour
• Data conversion functions
• String manipulation functions
• etc, etc.