Re: [Binari] MySQL chalenge

Thomas Van Parys schreef:

Kenny Billiau schreef:

...

Hi,

just to test our MySQL vigilance, here's a simple challenge: You've got a table with rows that could contain some data twice. Show me a query that removes (or selects) the data that's been entered twice, keeping one copy!

For example, a simple table with 2 two fields: id and name. 'id' Is auto incrementing and name could be inserted twice or more. 1 thomas 2 thomas 3 thomas 4 michiel 5 sofie 6 michiel 7 kenny 8 elisabeth 9 michiel 10 sofie

First one to solve it, I'll buy a beer :)

SELECT MIN(id), name FROM nice_table GROUP BY name;

DELETE FROM nice_table WHERE id NOT IN (SELECT MIN(id) FROM nice_table GROUP BY name); Beer me! (really)