DataStyle

Hi!
I did something like that:
torell=> set DataStyle to 'ISO';

and get something like this:
NOTICE: Unrecognized variable datastyle
SET VARIABLE

I try also with 'European' DataStyle - I remeber, that sometime ago this
command functions OK, and we've made no changes in configuration of
database.

So my question is:
If there is a way to set DataStyle manually?
And if it is possible to set it default 'European' to all users?
As I saw it seems, that every user has its own settings of this.
TIA
Rem

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Remigiusz Sokolowski e-mail: rems(at)gdansk(dot)sprint(dot)pl * *
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