Re: Schema and Namespace Oid confusion

Hello

On 2018-Dec-28, ZongtianHou wrote:

> I get somehow confused when I learn about namespace here, there are two questions,
> First, what is the difference between namespace and schema?

None.  Schema is the user-visible name for the feature; namespace is the
source code and system catalog level.

> Second, why the Oid of public namespace is 2200, the same between
> databases?

Not necessarily.  That's the initial value, but it's possible to drop
the public schema and create it afresh.

> Does oid is unique for every object across cluster? 

No, only inside each individual catalog are OIDs guaranteed unique.

> Does someone know about these clearly?

Yes.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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