mysql Update subquery Table is Specified twice

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mysql Update subquery Table is Specified twice



i try this subquery to decerese 1 i my quantity every time i execute this query , i think it will work on sqlServer but why its not working on mysql.
im getting this error
Table 't1' is specified twice, both as a target for 'UPDATE' and as a separate source for data



heres my code



Update tblbooks AS t1 set t1.Quantity = (Select t2.Quantity-1 from tblbooks AS t2 where t2.BookId = 123) where t1.BookId = 123




1 Answer
1



You don't need the subquery there - you can reassign a calculation on a column back to the same column:


UPDATE tblbooks
SET Quantity = Quantity - 1
WHERE BookId = 123





hahaha,i feel bad for me ,thank you
– Ivan
2 mins ago






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