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How to update a MySQL column with ascending numbers

Given the problem you have a new column postion and that column should be updated for all existing rows with ascending numbers. Furthermore these numbers should be generated by a special order. In order to achieve that you could do the following:

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execute "SET @pos := 0;" update " UPDATE pages SET position = ( SELECT @pos := @pos + 1 ) ORDER BY updated_at DESC;"

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Author of this card:

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Ulrich Berkmueller
Keywords:
increase, counter, increment, migration
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Posted by Ulrich Berkmueller to makandropedia