mysql - SQL: select all unique values in table A which are not in table B -

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i have table a

id  | name      | department ----------------------------- 0   | alice     | 1 0   | alice     | 2 1   | bob       | 1

and table b

id  | name ------------- 0   | alice

i want select unique ids in table not exist in table b. how can this?

select distinct id  tablea not exists (     select id      tableb      id = a.id )

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