Re: Exclude constraint on ranges : commutative containment : allow only complete containment

On 1/29/20 8:12 AM, Achilleas Mantzios wrote:
> Hello Dear Postgresql ppl,
> I have a table with date ranges and need to express the following
> constraint : allow overlaps only if there is complete containment, e.g.
> allow values in rows like :
> [2020-01-01,2020-01-31)
> [2020-01-02,2020-01-10)
> [2020-01-10,2020-01-20)
>
> but disallow rows like
>
> [2020-01-02,2020-01-10)
> [2020-01-08,2020-01-11)

I'm missing something. Can you provide a more complete example?

>
> I think that writing a new commutative range operator e.g. |<@@> which
> would return true if the left operand is either contained by or contains
> the right operand and false otherwise would solve this, I am just
> wondering if there is a more elegant and economical way to express this.
> (besides writing a trigger which is always an option).|
>
> --
> Achilleas Mantzios
> IT DEV Lead
> IT DEPT
> Dynacom Tankers Mgmt
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com