PHP/MySQL Database/mysql num rows

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

 
<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( $result );
print "<p>$num_rows women have added data to the table</p>\n";
mysql_close( $link );
?>
</body>
</html>



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

 
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();
?>



int mysql_num_rows ( resource result )

 
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); 

?>



Listing All Rows and Fields in a Table

 
<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( $result );
print "<p>$num_rows women have added data to the table</p>\n";
print "<table>";
while ( $a_row = mysql_fetch_row( $result ) ) {
  print "<tr>";
  foreach ( $a_row as $field ) {
    print "<td>".stripslashes($field)."</td>";
  }
  print "</tr>";
}
print "</table>";
mysql_close( $link );
?>
</body>
</html>



mysql_num_rows.php

 
<?
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.";
?>
Источник — «http://wbex.ru/index.php?title=PHP/MySQL_Database/mysql_num_rows&oldid=1027»