doufu7464 2014-01-06 04:27
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如果row为null则为null

So I have a column named "votes" which have the value "NULL" when the row first gets created. At the end of the day, I will add the votes coming from another table and put all the votes into the correct row. The problem is that if it is the first time the row gets votes, I will have to write SET votes = '$votes' but if it already has votes I will have to write SET votes = votes + '$votes'. Is there any easy way to detect if it is null or if it has an value?

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  • duannao1920 2014-01-06 04:35
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    Use Ifnull

    SET votes = IFNULL(votes, 0) + votes
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