Обсуждение: A minor error in "5.8 Inheritance"

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A minor error in "5.8 Inheritance"

От
Taiki Yamaguchi
Дата:
Hi,

I found a small error in "5.8 Inheritance" where it says:


Check constraints can be defined on tables within an inheritance
hierarchy. All check constraints on a parent table are automatically
inherited by all of its children. Other types of constraints are not
inherited, however.


However, "not null" constraints also will be inherited. Unique
constraints, primary key and foreign keys are not.


--
Taiki Yamaguchi


Re: A minor error in "5.8 Inheritance"

От
Tom Lane
Дата:
Taiki Yamaguchi <yamaguti@sra.co.jp> writes:
> I found a small error in "5.8 Inheritance" where it says:

> Check constraints can be defined on tables within an inheritance
> hierarchy. All check constraints on a parent table are automatically
> inherited by all of its children. Other types of constraints are not
> inherited, however.

> However, "not null" constraints also will be inherited. Unique
> constraints, primary key and foreign keys are not.

I think whoever wrote that had in mind that not-null constraints are a
special case of check constraints.  I agree it's clearer to spell it out
though.  Done, thanks for the report.

            regards, tom lane