add a temporary column with a value
select field1, field2, 'example' as TempField
from table1
This should work across different SQL implementations.
You mean staticly define a value, like this:
SELECT field1,
field2,
'example' AS newfield
FROM TABLE1
This will add a column called "newfield" to the output, and its value will always be "example".
I'm rusty on SQL but I think you could use select as to make your own temporary query columns.
select field1, field2, 'example' as newfield from table1
That would only exist in your query results, of course. You're not actually modifying the table.