Update if the register exists otherwise insert. MYSQL -


let's suppose have following table in mysql db

table: debt

id | customer | amount --------------------- 1  | peter    | $ 80 2  | john     | $120

what want sum new amount of money pending 1 given customer. i've been doing far select check if customer exist in table. if update register sum of previous value plus new one. if register doesn't exist proceed insert.

as can see i'm using 2 operations, select , update, or select , and insert.

my question if there way 1 single operation

https://dev.mysql.com/doc/refman/5.7/en/insert-on-duplicate.html

set amount = amount + ?? in on duplicate update clause.


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