Re: Unicode normalization SQL functions

On 2020-02-17 20:08, Daniel Verite wrote:
> Concerning execution speed, there's an excessive CPU usage when
> normalizing into NFC or NFKC. Looking at pre-existing code, it looks
> like recompose_code() in unicode_norm.c looping over the
> UnicodeDecompMain array might be very costly.

Yes, this is a known issue and I think room for future optimization work.

> Another point is that the ICU-based implementation appears
> to be significantly faster in all cases, which makes me wonder
> why ICU builds should not just use ICU instead of the PG-core
> implementation.

That would require linking libpq to ICU (for SASLprep), and in general 
would either make ICU required or require maintaining multiple 
implementations.  I don't think we're there yet.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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