Re: [HACKERS] proposal: session server side variables

On 12/29/2016 02:23 PM, Fabien COELHO wrote:
>
>> There is a singleton table :)
>>
>> create table foo(x integer unique not null default 1 check(x = 1), y 
>> integer);
>> insert into foo(y) values(100);
>> analyze foo;
>
> I know this one. It can be empty, which a singleton cannot be. For a 
> singleton table, you should have one and only one row, you cannot 
> insert or delete, so this is only part of the real thing.


Surely we can do a bit better than that, if that's what you really want. 
Create the table with an initial row and add a trigger preventing 
anything except update.


-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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