Re: byte-size of column values

On Tue, Oct 18, 2022 at 8:53 AM Dominique Devienne <ddevienne(at)gmail(dot)com>
wrote:

> Hi. I'm surprised by the result for bit(3) and char, when calling
> pg_column_size().
>
> Why 6, instead of 1? The doc does mention 5-8 bytes overhead, but I
> expected those for varying bit, not fixed-sized bit typed values. How
> come?
>
>
The base type is what matters, if the length of the actual type is a
parameter (the (n) part) the underlying type must be variable, and thus has
a component that says how long the actually stored value is.

> How does one store as compactedly as possible several small enums, on
> millions of rows?
>

int2
David J.

p.s., pretend char doesn't even exist.