[PHP] Explain that function!

[Hypertext]

Rand is how I judge when to use cron, I use
<?php
if((rand(0, 200)) == 1) {
// run cron
}
?>
Of course, once I launch Flyxa I will set the 200 higher, and as it gets more popular etc.

[Agnostic Bear]

It would return the same error message doing it either as:

 if(mysql_num_rows($result)==0) { } 

or

 $result = mysql_num_rows($query);
if($result==0) { } 

mysql_num_rows only converts the query result from mysql_query, it doesn't contact the database again.

Personally I prefer to use:

 if(mysql_num_rows($result)==0) { } 

It is just the same as putting it into a class and executing it:

 if($db->num_rows($query)==0) { } 

However the proper way in which to return the amount of rows is by doing it in the SQL itself:

select count(id) as total from tablename where 1=1

Both are proper ways. And both end up with the same result, it's just select count() is faster.

also @ jack, this is faster than yours if you insist on using mysql_num_rows:

<?php
$knownSinner = mysql_query("SELECT * FROM `idiotlist` WHERE `username` = 'knownSinner'");
$Howmany = mysql_num_rows($knownSinner);
if ($Howmany === 0)
{
    echo( 'You are only lying to yourself...' );
}
else
{
    echo( 'That\'s what i thought.' );
}
?>

[Jackboy]

It would return the same error message doing it either as:

 if(mysql_num_rows($result)==0) { } 

or

 $result = mysql_num_rows($query);
if($result==0) { } 

mysql_num_rows only converts the query result from mysql_query, it doesn't contact the database again.

Personally I prefer to use:

 if(mysql_num_rows($result)==0) { } 

It is just the same as putting it into a class and executing it:

 if($db->num_rows($query)==0) { } 

However the proper way in which to return the amount of rows is by doing it in the SQL itself:

select count(id) as total from tablename where 1=1

Ok thanks

Both are proper ways. And both end up with the same result, it's just select count() is faster.

also @ jack, this is faster than yours if you insist on using mysql_num_rows:

<?php
$knownSinner = mysql_query("SELECT * FROM `idiotlist` WHERE `username` = 'knownSinner'");
$Howmany = mysql_num_rows($knownSinner);
if ($Howmany === 0)
{
    echo( 'You are only lying to yourself...' );
}
else
{
    echo( 'That\'s what i thought.' );
}
?>

Sorry, i got used to doing mysql_num_rows, please explain why thats faster

[Agnostic Bear]

Ok thanks






Sorry, i got used to doing mysql_num_rows, please explain why thats faster

Doing a query then counting the rows is slower than just doing a query to return the count of the rows.

=== is faster than == when it's the right situation to use it, and ' is faster than ", use " when you need interpreted stuff (i.e: \n \t) else don't use it atall.

[Jackboy]

Doing a query then counting the rows is slower than just doing a query to return the count of the rows.

=== is faster than == when it's the right situation to use it, and ' is faster than ", use " when you need interpreted stuff (i.e: \n \t) else don't use it atall.

Ahh i never knew that, this thread is helping me learn things, cheers.