Ühel kenal päeval, R, 2007-03-23 kell 06:10, kirjutas Andrew -
Supernews:
On 2007-03-23, ITAGAKI Takahiro [EMAIL PROTECTED] wrote:
Thanks, it all made sense to me. My proposal was completely wrong.
Actually, I think your proposal is fundamentally correct, merely incomplete.
Doing
ITAGAKI Takahiro [EMAIL PROTECTED] writes:
I found LIKE operators are slower on multi-byte encoding databases
than single-byte encoding ones. It comes from difference between
MatchText() and MBMatchText().
We've had an optimization for single-byte encodings using
Ühel kenal päeval, N, 2007-03-22 kell 11:08, kirjutas Tom Lane:
ITAGAKI Takahiro [EMAIL PROTECTED] writes:
I found LIKE operators are slower on multi-byte encoding databases
than single-byte encoding ones. It comes from difference between
MatchText() and MBMatchText().
We've had an
Hannu Krosing [EMAIL PROTECTED] wrote:
We've had an optimization for single-byte encodings using
pg_database_encoding_max_length() == 1 test. I'll propose to extend it
in UTF-8 with locale-C case.
If this works for UTF8, won't it work for all the backend-legal
encodings?
I
Dennis Bjorklund [EMAIL PROTECTED] wrote:
The problem with the like pattern _ is that it has to know how long the
single caracter is that it should pass over. Say you have a UTF-8 string
with 2 characters encoded in 3 bytes ('ÖA'). Where the first character
is 2 bytes:
0xC3 0x96 'A'
ITAGAKI Takahiro skrev:
I guess it works well for % but not for _ , the latter has to know, how
many bytes the current (multibyte) character covers.
Yes, % is not used in trailing bytes for all encodings, but _ is
used in some of them. I think we can use the optimization for all
of the server
On 2007-03-22, Tom Lane [EMAIL PROTECTED] wrote:
ITAGAKI Takahiro [EMAIL PROTECTED] writes:
I found LIKE operators are slower on multi-byte encoding databases
than single-byte encoding ones. It comes from difference between
MatchText() and MBMatchText().
We've had an optimization for
On 2007-03-23, ITAGAKI Takahiro [EMAIL PROTECTED] wrote:
Thanks, it all made sense to me. My proposal was completely wrong.
Actually, I think your proposal is fundamentally correct, merely incomplete.
Doing octet-based rather than character-based matching of strings is a
_design goal_ of UTF8.
Hello,
I found LIKE operators are slower on multi-byte encoding databases
than single-byte encoding ones. It comes from difference between
MatchText() and MBMatchText().
We've had an optimization for single-byte encodings using
pg_database_encoding_max_length() == 1 test. I'll propose to extend
