mysql - Order of execution of SQL UPDATE while updating multiple values? -

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what sequence in values (separated commas) updated?

$command = sprintf('update %s set rating = ((rating * rating_count + %f) / (rating_count + 1.0)) , rating_count=rating_count+1 id=%d', $table, $ratinggiven, $id)`;

i want make sure that

rating = (rating * rating_count + %f) / (rating_count + 1.0)

is executed before

rating_count=rating_count+1

without firing 2 sql commands.

i not sure if update-value-statements executed in order in separated commas in mysql (or other db)?

i don't think matter update read current row , update upon based on existing values, , not ones in update.

so in both set operations, original value of rating_count used.


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