[PHP] Count number of rows in table.

[Martín marqués]

On Sáb 24 Ago 2002 11:19, Tony Harrison wrote:
> How would I count the number of rows in a mysql table with a WHERE clause?

select count(*) from table_name WHERE .....

Saludos... :-)

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Porqué usar una base de datos relacional cualquiera,
si podés usar PostgreSQL?
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Programador, Administrador, DBA | Centro de Telematica
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del Litoral
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[Tony Harrison]

And do I need to use any other functions like mysql_fetch_row() ?

"Martín marqués" <mar...@bugs.unl.edu.ar> wrote in message
news:200208241133...@bugs.unl.edu.ar...

[Matt]

>>> On Sáb 24 Ago 2002 11:19, Tony Harrison wrote:
>>> How would I count the number of rows in a mysql table with a WHERE
>>> clause?
> >
>> "Martín marqués" <mar...@bugs.unl.edu.ar> wrote in message
> > news:200208241133...@bugs.unl.edu.ar...
> > select count(*) from table_name WHERE .....
> >

>From: "Tony Harrison" <ton...@tharrison21.fsnet.co.uk>
> Sent: Saturday, August 24, 2002 5:54 PM
> Subject: Re: [PHP] Count number of rows in table.
>
> And do I need to use any other functions like mysql_fetch_row() ?
>

Yes. It's a regular sql statement, so you must fetch the results.

$sql = "select count(*) from table_name WHERE .....";
$result = mysql_query($sql) or die(mysql_error);
$row = mysql_fetch_row($result);
$rowCount=$row[0];

[Salamander]

or, you should be able to simply do this, without the cost of fetching
the results:

$result = mysql_query("SELECT count(*) FROM table WHERE");
$num_rows = mysql_num_rows($result);
echo "$num_rows Rows\n";

>> $sql = "select count(*) from table_name WHERE .....";
>> $result = mysql_query($sql) or die(mysql_error);
>> $row = mysql_fetch_row($result);
>> $rowCount=$row[0];

> or

> $sql = "select count(*) from table_name WHERE .....";
> $result = mysql_query($sql) or die(mysql_error);

> $rowCount=mysql_result($result);
>
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>

[Bas Jobsen]

> $sql = "select count(*) from table_name WHERE .....";
> $result = mysql_query($sql) or die(mysql_error);
> $row = mysql_fetch_row($result);
> $rowCount=$row[0];

or

$sql = "select count(*) from table_name WHERE .....";
$result = mysql_query($sql) or die(mysql_error);

$rowCount=mysql_result($result);

[Jason Wong]

On Sunday 25 August 2002 22:07, salamander wrote:
> or, you should be able to simply do this, without the cost of fetching
> the results:
>
> $result = mysql_query("SELECT count(*) FROM table WHERE");
> $num_rows = mysql_num_rows($result);
> echo "$num_rows Rows\n";

No. This only returns 1 row regardless. "SELECT COUNT(*) FROM ..." only
returns a single row with a single column containing the row count. Using
mysql_num_rows() on that will always return 1.

--
Jason Wong -> Gremlins Associates -> www.gremlins.com.hk
Open Source Software Systems Integrators
* Web Design & Hosting * Internet & Intranet Applications Development *

/*
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[Salamander]

okay, so then a "select *" and then a num_rows ...

[Chris Shiflett]

I think you were on the right track with your first response. Selecting
a count(*) gives you the number of rows returned without the overhead of
actually returning all of the rows to PHP. Most people will rename the
count as something more easy to reference (and/or more descriptive) in
the result set:

select count(*) as num_movies from movies where actor='Val Kilmer';

What Jason was trying to explain is that the data you are looking for is
actually in the query you performed. You specifically queried for the
number of rows. Your result set consists of a single row with a single
element, num_movies.

Happy hacking.

Chris