in reply to Compare items in DB

CREATE TEMPORARY TABLE foo (
    bar INT NOT NULL
);
INSERT INTO foo (bar) VALUES (1),(2),(4),(5);

SELECT foo.bar
  FROM foo LEFT OUTER JOIN num_table ON (foo.bar = num_table.num)
 WHERE num_table.primary_key_column IS NULL
;

[download]
Of course, I wouldn't use that unless I could explain it.
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

Replies are listed 'Best First'.
Re^2: Compare items in DB
by Anonymous Monk on Mar 06, 2008 at 20:54 UTC
    Is this for the reverse?
[reply]
      Look up what LEFT OUTER JOIN does before asking.
      My criteria for good software:
      1. Does it work?
      2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?
[reply]

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