Finding missing records in SQL table

The table stored in mySQL database contains the ID column, which is a number between 2000000 and 4000000. The numbers are ordered and sequential (increment by 1). I need a SQL query which can loop through this range and find all missing records (the database should contain 2000000 records, but currently contains only 1800000).

Thank you, experts!
cyber-33Asked:
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Daniel WilsonCommented:
Create a table of numbers, 2 million to 4 million.
create table numbers (N bigint);
then do a loop that inserts the numbers you need.

Next select the numbers that have no counterpart in your table.

Select N from numbers where not exists (Select ID from MyTable where ID = N);
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cyber-33Author Commented:
I would need a script that populates the new table you are suggesting.

Also, there should be a simpler way finding the missing records by using a cursor and a single query.
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Tomas Helgi JohannssonCommented:
Hi!

Try this sql to find the missing values (gaps) in your sequence.

SELECT a.id+1 AS start, MIN(b.id) - 1 AS end
    FROM mytable AS a, mytable AS b
    WHERE a.id < b.id
    GROUP BY a.id
    HAVING start < MIN(b.id)

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Regards,
       Tomas Helgi
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cyber-33Author Commented:
Tomas, I tried running the query but it never came back... Can you please explain the logic behind it?
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Ray PaseurCommented:
... there should be a simpler way finding the missing records
Really?  How often do you need to do this?  If it's more than once, there is something suspicious about the overall design.  My sense is that any solution would be the best solution.  And with only two million records it's not a large process.

Please post the CREATE TABLE statement and show us some of your test data.  Armed with that we can almost certainly give you a tested-and-working code sample.
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