PHP function to backup and import database using MYSQLI

mysql_backup_import.php

<?php
/**
 * @author awan < nawa (at) yahoo (dot) com >
 * 
 */
 
 
/**
 * Function to build SQL /Importing SQL DATA
 *
 * @param string $args as the queries of sql data , yopu could use file get contents to read data args
 * @param string $dbhost database host
 * @param string $dbuser database user
 * @param string $dbpass database password
 * @param string $dbname database name
 *
 * @return string complete if complete
 */

function mysqli_import_sql( $args , $dbhost, $dbuser, $dbpass ,$dbname ) {

  // check mysqli extension installed
  if( ! function_exists('mysqli_connect') ) {
    die(' This scripts need mysql extension to be running properly ! please resolve!!');
  }

	$mysqli = @new mysqli( $dbhost, $dbuser, $dbpass, $dbname );
	if( $mysqli->connect_error ) {
    		print_r( $mysqli->connect_error );
    		return false;
  	}

    $querycount = 11;
    $queryerrors = '';
    $lines = (array) $args;
    if( is_string( $args ) ) {
      $lines =  array( $args ) ;
    }

    if ( ! $lines ) {
      return '' . 'cannot execute ' . $args;
    }

    $scriptfile = false;
    foreach ($lines as $line) {
      $line = trim( $line );
      // if have -- comments add enters
      if (substr( $line, 0, 2 ) == '--') {
          $line = "\n" . $line;
      }
      if (substr( $line, 0, 2 ) != '--') {
        $scriptfile .= ' ' . $line;
        continue;
      }
    }

    $queries = explode( ';', $scriptfile );
    foreach ($queries as $query) {
      $query = trim( $query );
      ++$querycount;

      if ( $query == '' ) {
        continue;
      }


      if ( ! $mysqli->query( $query ) ) {
        $queryerrors .= '' . 'Line ' . $querycount . ' - ' . $mysqli->error . '<br>';
        continue;
      }
    }


    if ( $queryerrors ) {
      return '' . 'There was an error on File: ' . $filename . '<br>' . $queryerrors;
    }
    
    if( $mysqli && ! $mysqli->error ) {
      @$mysqli->close();
    }   

    return 'complete dumping database !';
}

/**
 * MYSQL EXPORT TO GZIP 
 * exporting database to sql gzip compression data.
 * if directory writable will be make directory inside of directory if not exist, else wil be die
 *
 * @param string directory , as the directory to put file
 * @param $outname as file name just the name !, if file exist will be overide as numeric next ++ as name_1.sql.gz , name_2.sql.gz next ++
 *
 * @param string $dbhost database host
 * @param string $dbuser database user
 * @param string $dbpass database password
 * @param string $dbname database name
 *
 */
function backup_database( $directory, $outname , $dbhost, $dbuser, $dbpass ,$dbname ) {
  
  // check mysqli extension installed
  if( ! function_exists('mysqli_connect') ) {
    die(' This scripts need mysql extension to be running properly ! please resolve!!');
  }

	$mysqli = @new mysqli($dbhost, $dbuser, $dbpass, $dbname);
	
	if( $mysqli->connect_error ) {
		print_r( $mysqli->connect_error );
		return false;
	}

  	$dir = $directory;
  	$result = '<p> Could not create backup directory on :'.$dir.' Please Please make sure you have set Directory on 755 or 777 for a while.</p>';  
  	$res = true;
  	if( ! is_dir( $dir ) ) {
  	  if( ! @mkdir( $dir, 755 )) {
  	    $res = false;
  	  }
  	}

  $n = 1;
  if( $res ) {

    $name     = $outname;
    # counts
    if( file_exists($dir.'/'.$name.'.sql.gz' ) ) {

      for($i=1;@count( file($dir.'/'.$name.'_'.$i.'.sql.gz') );$i++){
        $name = $name;
        if( ! file_exists( $dir.'/'.$name.'_'.$i.'.sql.gz') ) {
          $name = $name.'_'.$i;
          break;
        }
      }
    }

    $fullname = $dir.'/'.$name.'.sql.gz'; # full structures

    if( ! $mysqli->error ) {
      $sql = "SHOW TABLES";
      $show = $mysqli->query($sql);
      while ( $r = $show->fetch_array() ) {
        $tables[] = $r[0];
      }

      if( ! empty( $tables ) ) {

  //cycle through
  $return = '';
  foreach( $tables as $table )
  {
    $result     = $mysqli->query('SELECT * FROM '.$table);
    $num_fields = $result->field_count;
    $row2       = $mysqli->query('SHOW CREATE TABLE '.$table );

    $row2       = $row2->fetch_row();
    $return    .= 
"\n
-- ---------------------------------------------------------
--
-- Table structure for table : `{$table}`
--
-- ---------------------------------------------------------

".$row2[1].";\n";

    for ($i = 0; $i < $num_fields; $i++) 
    {

      $n = 1 ;
      while( $row = $result->fetch_row() )
      { 
        

        if( $n++ == 1 ) { # set the first statements
          $return .= 
"
--
-- Dumping data for table `{$table}`
--

";  
        /**
         * Get structural of fields each tables
         */
        $array_field = array(); #reset ! important to resetting when loop 
         while( $field = $result->fetch_field() ) # get field
        {
          $array_field[] = '`'.$field->name.'`';
          
        }
        $array_f[$table] = $array_field;
        // $array_f = $array_f;
        # endwhile
        $array_field = implode(', ', $array_f[$table]); #implode arrays

          $return .= "INSERT INTO `{$table}` ({$array_field}) VALUES\n(";
        } else {
          $return .= '(';
        }
        for($j=0; $j<$num_fields; $j++) 
        {
          
          $row[$j] = str_replace('\'','\'\'', preg_replace("/\n/","\\n", $row[$j] ) );
          if ( isset( $row[$j] ) ) { $return .= is_numeric( $row[$j] ) ? $row[$j] : '\''.$row[$j].'\'' ; } else { $return.= '\'\''; }
          if ($j<($num_fields-1)) { $return.= ', '; }
        }
          $return.= "),\n";
      }
      # check matching
      @preg_match("/\),\n/", $return, $match, false, -3); # check match
      if( isset( $match[0] ) )
      {
        $return = substr_replace( $return, ";\n", -2);
      }

    }
    
      $return .= "\n";

  }

$return = 
"-- ---------------------------------------------------------
--
-- SIMPLE SQL Dump
-- 
-- nawa (at) yahoo (dot) com
--
-- Host Connection Info: ".$mysqli->host_info."
-- Generation Time: ".date('F d, Y \a\t H:i A ( e )')."
-- Server version: ".mysql_get_server_info()."
-- PHP Version: ".PHP_VERSION."
--
-- ---------------------------------------------------------\n\n

SET SQL_MODE = \"NO_AUTO_VALUE_ON_ZERO\";
SET time_zone = \"+00:00\";


/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;
".$return."
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;";

# end values result

    @ini_set('zlib.output_compression','Off');
    $gzipoutput = gzencode( $return, 9);

 if(  @ file_put_contents( $fullname, $gzipoutput  ) ) { # 9 as compression levels
  
    $result = $name.'.sql.gz'; # show the name
  
  } else { # if could not put file , automaticly you will get the file as downloadable

    $result = false;   
    // various headers, those with # are mandatory
    header('Content-Type: application/x-gzip'); // change it to mimetype
    header("Content-Description: File Transfer");
    header('Content-Encoding: gzip'); #
    header('Content-Length: '.strlen( $gzipoutput ) ); #
    header('Content-Disposition: attachment; filename="'.$name.'.sql.gz'.'"');
    header('Cache-Control: no-cache, no-store, max-age=0, must-revalidate');
    header('Connection: Keep-Alive');
    header("Content-Transfer-Encoding: binary");
    header('Expires: 0');
    header('Pragma: no-cache');
    
    echo $gzipoutput;

  }

       } else {

         $result = '<p>Error when executing database query to export.</p>'.$mysqli->error;
       
       }
     }

 } else {
      $result = '<p>Wrong mysqli input</p>';
 }
 
 if( $mysqli && ! $mysqli->error ) {
      @$mysqli->close();
 }

  return $result;

}