Re: Per-column collation

On 15.11.2010 21:42, Peter Eisentraut wrote:
> On mån, 2010-11-15 at 11:34 +0100, Pavel Stehule wrote:
>> I am checking a patch. I found a problem with initdb
>
> Ah, late night brain farts, it appears.  Here is a corrected version.

Some random comments:

In syntax.sgml:

> +    The <literal>COLLATE</literal> clause overrides the collation of
> +    an expression.  It is appended to the expression at applies to:

That last sentence doesn't parse.


Would it be possible to eliminate the ExecEvalCollateClause function 
somehow? It just calls through the argument. How about directly 
returning the argument ExprState in ExecInitExpr?

get_collation_name() returns the plain name without schema, so it's not 
good enough for use in ruleutils.c. pg_dump is also ignoring collation's 
schema.

Have you done any performance testing? Functions like text_cmp can be a 
hotspot in sorting, so any extra overhead there might be show up in tests.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com