Generating a range of numbers in MySQL

Question

How do I generate a range of consecutive numbers (one per line) from a MySQL query so that I can insert them into a table?

For example:

nr
1
2
3
4
5
         


        

Answer 1

The "shortest" way i know (in MySQL) to create a table with a long sequence is to (cross) join an existing table with itself. Since any (common) MySQL server has the information_schema.COLUMNS table i would use it:

DROP TABLE IF EXISTS seq;
CREATE TABLE seq (i MEDIUMINT AUTO_INCREMENT PRIMARY KEY)
    SELECT NULL AS i
    FROM information_schema.COLUMNS t1
    JOIN information_schema.COLUMNS t2
    JOIN information_schema.COLUMNS t3
    LIMIT 100000; -- <- set your limit here

Usually one join should be enough to create over 1M rows - But one more join will not hurt :-) - Just don't forget to set a limit.

If you want to include 0, you should "remove" the AUTO_INCEMENT property.

ALTER TABLE seq ALTER i DROP DEFAULT;
ALTER TABLE seq MODIFY i MEDIUMINT;

Now you can insert 0

INSERT INTO seq (i) VALUES (0);

and negative numbers as well

INSERT INTO seq (i) SELECT -i FROM seq WHERE i <> 0;

You can validate the numbers with

SELECT MIN(i), MAX(i), COUNT(*) FROM seq;