mysql - Difference between two datetime entries -

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select eta,sta `schedule` `num`="5567";

2013-08-26 18:37:00 2013-08-26 18:30:00

select datediff(eta,sta) `schedule` `num`="5567";

0

why result 0 instead of 7 (i.e. minutes)?

datediff give result in days.

select hour (eta - sta) `schedule` `num`="5567";

an alternative hour difference.


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