PHP/MySQL Database/mysql num rows

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Finding the Number of Rows Returned by a SELECT Statement with mysql_num_rows()

   <source lang="html4strict">

<html> <head> <title>Using mysql_num_rows()</title> </head> <body> <?php $user = "root"; $pass = ""; $db = "mydatabase"; $link = mysql_connect( "localhost", $user, $pass ); if ( ! $link ) {

 die( "Couldn"t connect to MySQL: ".mysql_error() );

} mysql_select_db( $db, $link ) or die ( "Couldn"t open $db: ".mysql_error() ); $result = mysql_query( "SELECT * FROM domains where sex="F"" ); $num_rows = mysql_num_rows( $result );

print "

$num_rows women have added data to the table

\n";

mysql_close( $link ); ?> </body> </html>

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function mysql_num_rows() determines the number of rows returned from a SELECT query statement.

   <source lang="html4strict">

Its syntax is: int mysql_num_rows (int result) <? @mysql_connect("localhost", "root","") or die("Could not connect to MySQL server!"); @mysql_select_db("mydatabase") or die("Could not select database!"); $query = "SELECT title FROM mytable WHERE title LIKE \"p%\""; $result = mysql_query($query); print "Total rows selected: ".mysql_num_rows($result); mysql_close(); ?>

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int mysql_num_rows ( resource result )

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Building Queries on the Fly <?php function opendatabase ($host,$user,$pass) {

   try { 
       if ($db = mysql_connect ($host,$user,$pass)){ 
           return $db; 
       } else { 
           throw new exception ("Sorry, could not connect to mysql."); 
       } 
   } catch (exception $e) { 
       echo $e->getmessage (); 
   } 

} function selectdb ($whichdb, $db){

   try { 
       if (!mysql_select_db ($whichdb,$db)){ 
           throw new exception ("Sorry, database could not be opened."); 
       } 
   } catch (exception $e) { 
       echo $e->getmessage(); 
   } 

} function closedatabase ($db){

   mysql_close ($db); 

} $db = opendatabase ("localhost","root",""); selectdb ("mydatabase",$db); $_POST["user"] = "root"; $_POST["pass"] = "";

function validatelogin ($user,$pass){

   mysql_real_escape_string ($user); 
   mysql_real_escape_string ($pass); 
   $thequery = "SELECT * FROM userlogin WHERE username="$user" AND password="$pass""; 
   if ($aquery = mysql_query ($thequery)){ 
       if (mysql_num_rows ($aquery) > 0){ 
           return true; 
       } else { 
           return false; 
       } 
   } else { 
       echo mysql_error(); 
   } 

}

if (validatelogin ($_POST["user"],$_POST["pass"])){

   echo "You have successfully logged in."; 

} else {

   echo "Sorry, you have an incorrect username and/or password."; 

} //Then close the database. closedatabase ($db);

?>

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Listing All Rows and Fields in a Table

   <source lang="html4strict">

<html> <head> <title>Selecting Data</title> </head> <body> <?php $user = "root"; $pass = ""; $db = "mydatabase"; $link = mysql_connect( "localhost", $user, $pass ); if ( ! $link ) {

 die( "Couldn"t connect to MySQL: ".mysql_error() );

} mysql_select_db( $db, $link ) or die ( "Couldn"t open $db: ".mysql_error() ); $result = mysql_query( "SELECT * FROM domains where sex="F"" ); $num_rows = mysql_num_rows( $result );

print "

$num_rows women have added data to the table

\n"; print ""; while ( $a_row = mysql_fetch_row( $result ) ) { print ""; foreach ( $a_row as $field ) { print "";
 }
print ""; } print "
".stripslashes($field)."
";

mysql_close( $link ); ?> </body> </html>

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mysql_num_rows.php

   <source lang="html4strict">

<? mysql_connect("localhost","root",""); mysql_select_db("mydatabase"); $query = "SELECT title FROM mytable WHERE myvalue > 15.99"; $result = mysql_query($query); echo "There are ".mysql_num_rows($result)." product(s) priced above \$15.99."; ?>

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