mysql - SQL Query Update field depending on subquery -

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i need sql query. table users has 3 fields: name, iduser, idgroup.

one user can appear many times on same table same iduser , different idgroups.

field name should update new value if has changed.

if there no exists row given iduser , idgroup has inserted new row.

if exists(select 1 users iduser=3 , idgroup=4) begin      update users set name='new name' iduser=3 , idgroup=4 end else      insert users values('name',5,3) end

my sql query sintax wrong can't use it, how achieve need?

i'm using mysql database (managed phpmyadmin) , doing insert lua script.

you need make sure have right unique keys in place.

alter table users add unique `unique_index`(`iduser`, `idgroup`);

then, should able run insert/update:

insert users (name, iduser, idgroup)  values ('name value',5,3)  on duplicate key update name = values(name) name <> values(name)

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