PostgreSQL/Constraints/Column Relations

Specifying the column relation

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postgres=# postgres=# postgres=# CREATE TABLE products ( postgres(# product_no integer, postgres(# price numeric CHECK (price > 0), postgres(# discounted_price numeric CHECK (discounted_price > 0), postgres(# CHECK (price > discounted_price) postgres(# ); CREATE TABLE postgres=# drop table products; DROP TABLE postgres=# postgres=#

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