Re: why the need for is null?

In an attempt to throw the authorities off his trail, bbn-pgsql(dot)general(at)clansoft(dot)dk (Baldur Norddahl) transmitted:
> How come "X=null" is not the same as "X is null"?

Because NULL is not really a "value" in SQL. Nothing can ever be
equal to a NULL, and that includes another NULL.

In Some Pseudo-SQL Database Systems, NULL is treated as a sort of
"zero" value, which is contrary to the SQL standards.

I seem to recall that in Microsoft's port of Sybase SQL Server,
there's some syntactic sugar that "x = NULL" is treated as if it were
querying "x is NULL."

It would presumably be _possible_ to modify PostgreSQL's query parser
to handle "x = NULL" similarly; feel free to submit a patch to that
end, if you consider it a vital change to make.
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