PostgreSQL table with two integer array columns, say a = [1,2,3,4] and b = [1,2,3,4,5,6]. The items of b that are not in a are 5,6, so as a query result I want an array [5,6].
How to achieve this in PostgreSQL?
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Jochen Schwarze
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Possible duplicate of [Postgres - Function to return the intersection of 2 ARRAYs?](https://stackoverflow.com/questions/756871/postgres-function-to-return-the-intersection-of-2-arrays) – Gholamali Irani Dec 13 '17 at 19:07
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2see: intarray Operators on https://www.postgresql.org/docs/current/static/intarray.html – Gholamali Irani Dec 13 '17 at 19:11
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so simple... with intarray extension installed, its simply `select a-b` – Jochen Schwarze Dec 13 '17 at 19:16
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with intarray extension installed, one may simply select a-b, cp. https://www.postgresql.org/docs/current/static/intarray.html
Jochen Schwarze
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