Re: Theory of operation of collation patch

On 07.03.2011 17:43, Tom Lane wrote:
> because two expressions that are equal() must necessarily have the same collation
> property.

Peter, Tom,

I am not able to see this.

If 'abc' == 'abc' is not collation depending at all. It is only
encoding depending.

Collation is only needed for upper(), lower() and sorting.
Means it tells if e.g. upper('i') will get Y or I.
It tells if the German s-umlaut will be sorted together with 's' or
after 'z'.

Btw. the follows on implementing collations will be different -
and I hope Peter is aware of it.

My experience is that a huge follow will be that users will complain
that the
sorting isn't correct even when it is correct.

Susanne

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Susanne Ebrecht - 2ndQuadrant
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