Question

I’m looking for the best way to select numbers directly from an in clause.

Basically like:

SELECT * FROM (2,6,1,8);

That doesn’t work. I can do it this way:

SELECT Lv FROM (  SELECT Level LV

                  FROM DUAL

                  CONNECT BY Level < 20)

WHERE Lv IN (2,6,1,8);

But that seems to be a bit clunky. Is there a more elegant way?

Answer 1

It’s more elegant if you materialize an auxiliary numbers table:

SELECT num FROM numbers WHERE num IN (2,6,1,8);

And this is also useful when combined with another table.

For instance, I’ve had a case where I needed to populate large configuration tables with changes from piecewise results:

Big SP or Excel sheet or report identifies missing cost centers in config gives a large set of results which need to be inserted with varying data in some groups.

Paste partial results into a individual comma separated lists:

INSERT INTO {stuff}
SELECT {stuff}, 130 as line_item
FROM numbers
WHERE numbers.num IN ({pasted a section of results})

INSERT INTO {stuff}
SELECT {stuff}, 135 as line_item
FROM numbers
WHERE numbers.num IN ({pasted another section of results})