PHP Query and delete database multi-column duplicate data method (using Array function Implementation), multi-column Array _php tutorial

PHP Query and delete database multi-column duplicate data method (using Array function Implementation), multi-column array

This article explains how PHP queries and removes multiple columns of data from a database. Share to everyone for your reference, as follows:

<?php$con = mysql_connect ("localhost", "root", "" "), if (! $con) {die    (' Could not connect: '. Mysql_error ());} $db _selected = mysql_select_db ("test_db", $con), if (! $db _selected) {die    ("can/' t use test_db:". Mysql_error ());} $sql = "SELECT * from Friend", $result =mysql_query ($sql, $con) and while ($myrow =mysql_fetch_row ($result)) {    $arr _data[ $myrow [0]]= $myrow [1]. " -". $myrow [2];} $arr _unique=array_unique ($arr _data), $arr _rep=array_diff_assoc ($arr _data, $arr _unique);//display front and rear volume echo count ($arr _ Data). " -". Count ($arr _unique); foreach ($arr _rep as $key + $value) {  $sql _del =" DELETE from friend WHERE id = ' {$key} ' "; 
  
    $result =mysql_query ($sql _del, $con);} Some code mysql_close ($con);? >
  

More readers interested in PHP related content can view the topic: "PHP Primer for Object-oriented programming", "PHP String Usage Summary", "Php+mysql Database Operations Primer" and "PHP common database Operation Skills Summary"

I hope this article is helpful to you in PHP programming.

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