Обсуждение: RE: Simple Question: Case sensitivity
Abe: It's an SQL thing or a scripting thing. It's probably easiest and
safest in the SQL:
select firstname, surname from employees
where upper(firstname) like upper('%$criteria%') or
upper(surname) like upper('%$criteria%')
That is, force the column and the search string to uppercase befor
comparing, and it won't matter how it's stored in the database.
Cheers!
--
David Hancock
-----Original Message-----
From: Abe
To: pgsql-general@postgresql.org
Sent: 12/10/00 7:23 AM
Subject: [GENERAL] Simple Question: Case sensitivity
This is probably an easy question for most but here goes:
I am using PHP3 and postgres 6.5
I am trying to do a search on a peoples database and it works fine
except
for the fact that I want to make it case insensitive as some in the
database
are Smith and some are jones. Is this a scripting thing or can it be
done
in my query.
Here is the query:
$sql = "select surname, firstname, title, company, worktel, ext,
hometel,
mobile, email, emailtwo from employees where firstname like
'%$criteria%' or
surname like '%$criteria%'";
Thanks in advance,
Abe
Thanks David,
works a treat!
Abe
----- Original Message -----
From: "Hancock, David (DHANCOCK)" <DHANCOCK@arinc.com>
To: "'Abe '" <abe@fish.tm>; <pgsql-general@postgresql.org>
Sent: Sunday, December 10, 2000 12:48 PM
Subject: RE: [GENERAL] Simple Question: Case sensitivity
> Abe: It's an SQL thing or a scripting thing. It's probably easiest and
> safest in the SQL:
>
> select firstname, surname from employees
> where upper(firstname) like upper('%$criteria%') or
> upper(surname) like upper('%$criteria%')
>
> That is, force the column and the search string to uppercase befor
> comparing, and it won't matter how it's stored in the database.
>
> Cheers!
> --
> David Hancock
>
> -----Original Message-----
> From: Abe
> To: pgsql-general@postgresql.org
> Sent: 12/10/00 7:23 AM
> Subject: [GENERAL] Simple Question: Case sensitivity
>
> This is probably an easy question for most but here goes:
>
> I am using PHP3 and postgres 6.5
>
> I am trying to do a search on a peoples database and it works fine
> except
> for the fact that I want to make it case insensitive as some in the
> database
> are Smith and some are jones. Is this a scripting thing or can it be
> done
> in my query.
>
> Here is the query:
>
> $sql = "select surname, firstname, title, company, worktel, ext,
> hometel,
> mobile, email, emailtwo from employees where firstname like
> '%$criteria%' or
> surname like '%$criteria%'";
>
> Thanks in advance,
> Abe
>
"Hancock, David (DHANCOCK)" <DHANCOCK@arinc.com> writes:
> Abe: It's an SQL thing or a scripting thing. It's probably easiest and
> safest in the SQL:
>
> select firstname, surname from employees
> where upper(firstname) like upper('%$criteria%') or
> upper(surname) like upper('%$criteria%')
>
> That is, force the column and the search string to uppercase befor
> comparing, and it won't matter how it's stored in the database.
Related to this, is there any way to make an index for a table
case-insensitive? If you have an index, but use upper() in the select,
the index is not used.
Tomas
On 11 Dec 2000, Tomas Berndtsson wrote:
> "Hancock, David (DHANCOCK)" <DHANCOCK@arinc.com> writes:
>
> > Abe: It's an SQL thing or a scripting thing. It's probably easiest and
> > safest in the SQL:
> >
> > select firstname, surname from employees
> > where upper(firstname) like upper('%$criteria%') or
> > upper(surname) like upper('%$criteria%')
> >
> > That is, force the column and the search string to uppercase befor
> > comparing, and it won't matter how it's stored in the database.
>
> Related to this, is there any way to make an index for a table
> case-insensitive? If you have an index, but use upper() in the select,
> the index is not used.
You can create your index as upper or lower and it'll be used in a
select that uses upper().
Vince.
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Tomas Berndtsson <tomas@nocrew.org> writes:
> Related to this, is there any way to make an index for a table
> case-insensitive? If you have an index, but use upper() in the select,
> the index is not used.
Sure, make a functional index:
play=> create table foo (f1 text);
CREATE
play=> create index fooi on foo (upper(f1));
CREATE
This index will be considered for queries like:
play=> explain select * from foo where upper(f1) = 'z';
NOTICE: QUERY PLAN:
Index Scan using fooi on foo (cost=0.00..8.16 rows=10 width=12)
EXPLAIN
play=> explain select * from foo where upper(f1) > 'a' and upper(f1) < 'z';
NOTICE: QUERY PLAN:
Index Scan using fooi on foo (cost=0.00..8.21 rows=10 width=12)
EXPLAIN
You can use the same sort of ploy for lower() or any other simple
function of the table's columns. Don't go overboard with a ton of
indexes though; remember each index costs time when updating the
table...
regards, tom lane
Tom Lane <tgl@sss.pgh.pa.us> writes:
> Tomas Berndtsson <tomas@nocrew.org> writes:
> > Related to this, is there any way to make an index for a table
> > case-insensitive? If you have an index, but use upper() in the select,
> > the index is not used.
>
> Sure, make a functional index:
>
> play=> create table foo (f1 text);
> CREATE
> play=> create index fooi on foo (upper(f1));
> CREATE
Ah, great, thanks. Couldn't see anything about that in the manual.
> This index will be considered for queries like:
>
> play=> explain select * from foo where upper(f1) = 'z';
Don't you need upper('z')?
Tomas
Simply create a functional index:
CREATE INDEX foo ON employees (UPPER(firstname));
However, I have just tried this, and it doesn't work for some reason. Anybody?
Cheers...
MikeA
-----Original Message-----
From: Tomas Berndtsson [mailto:tomas@nocrew.org]
Sent: 11 December 2000 10:49
To: Hancock, David (DHANCOCK)
Cc: 'pgsql-general@postgresql.org '
Subject: Re: [GENERAL] Simple Question: Case sensitivity
"Hancock, David (DHANCOCK)" <DHANCOCK@arinc.com> writes:
> Abe: It's an SQL thing or a scripting thing. It's probably easiest and
> safest in the SQL:
>
> select firstname, surname from employees
> where upper(firstname) like upper('%$criteria%') or
> upper(surname) like upper('%$criteria%')
>
> That is, force the column and the search string to uppercase befor
> comparing, and it won't matter how it's stored in the database.
Related to this, is there any way to make an index for a table
case-insensitive? If you have an index, but use upper() in the select,
the index is not used.
Tomas
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Tomas Berndtsson <tomas@nocrew.org> writes:
>> This index will be considered for queries like:
>>
>> play=> explain select * from foo where upper(f1) = 'z';
> Don't you need upper('z')?
yup ... or at least 'Z' ... sloppy example :-(
regards, tom lane