PDO MySQL backups function

Question

This function here http://davidwalsh.name/backup-mysql-database-php

Has been floating around the internets for a while and is pretty famous, but it's using old MySQL API. Does anyone have the same but in PDO? If not does anyone want to make one?

Is it even possible, I read somewhere that PDO doesn't do SHOW CREATE TABLE - is that right?

Answer 1

To anyone looking for the function which acts like the mysqldump, here is the latest draft, with the imperfections discussed in the comments above/below ironed out.

require 'login.php';
$DBH = new PDO("mysql:host=$db_hostname;dbname=$db_database; charset=utf8", $db_username, $db_password);

//put table names you want backed up in this array.
//leave empty to do all
$tables = array();

backup_tables($DBH, $tables);

function backup_tables($DBH, $tables) {
    $DBH->setAttribute(PDO::ATTR_ORACLE_NULLS, PDO::NULL_NATURAL);

    //Script Variables
    $compression = false;
    $BACKUP_PATH = "";
    $nowtimename = time();

    //create/open files
    if ($compression) {
        $zp = gzopen($BACKUP_PATH . $nowtimename . '.sql.gz', "a9");
    } else {
        $handle = fopen($BACKUP_PATH . $nowtimename . '.sql', 'a+');
    }

    //array of all database field types which just take numbers
    $numtypes = array('tinyint', 'smallint', 'mediumint', 'int', 'bigint', 'float', 'double', 'decimal', 'real');

    //get all of the tables
    if (empty($tables)) {
        $pstm1 = $DBH->query('SHOW TABLES');
        while ($row = $pstm1->fetch(PDO::FETCH_NUM)) {
            $tables[] = $row[0];
        }
    } else {
        $tables = is_array($tables) ? $tables : explode(',', $tables);
    }

    //cycle through the table(s)

    foreach ($tables as $table) {
        $result = $DBH->query("SELECT * FROM $table");
        $num_fields = $result->columnCount();
        $num_rows = $result->rowCount();

        $return = "";
        //uncomment below if you want 'DROP TABLE IF EXISTS' displayed
        //$return.= 'DROP TABLE IF EXISTS `'.$table.'`;';

        //table structure
        $pstm2 = $DBH->query("SHOW CREATE TABLE $table");
        $row2 = $pstm2->fetch(PDO::FETCH_NUM);
        $ifnotexists = str_replace('CREATE TABLE', 'CREATE TABLE IF NOT EXISTS', $row2[1]);
        $return .= "\n\n" . $ifnotexists . ";\n\n";

        if ($compression) {
            gzwrite($zp, $return);
        } else {
            fwrite($handle, $return);
        }
        $return = "";

        //insert values
        if ($num_rows) {
            $return = 'INSERT INTO `' . $table . '` (';
            $pstm3 = $DBH->query("SHOW COLUMNS FROM $table");
            $count = 0;
            $type = array();

            while ($rows = $pstm3->fetch(PDO::FETCH_NUM)) {
                if (stripos($rows[1], '(')) {
                    $type[$table][] = stristr($rows[1], '(', true);
                } else {
                    $type[$table][] = $rows[1];
                }

                $return .= "`" . $rows[0] . "`";
                $count++;
                if ($count < ($pstm3->rowCount())) {
                    $return .= ", ";
                }
            }

            $return .= ")" . ' VALUES';

            if ($compression) {
                gzwrite($zp, $return);
            } else {
                fwrite($handle, $return);
            }
            $return = "";
        }
        $count = 0;
        while ($row = $result->fetch(PDO::FETCH_NUM)) {
            $return = "\n\t(";

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

                //$row[$j] = preg_replace("\n","\\n",$row[$j]);

                if (isset($row[$j])) {

                    //if number, take away "". else leave as string
                    if ((in_array($type[$table][$j], $numtypes)) && (!empty($row[$j]))) {
                        $return .= $row[$j];
                    } else {
                        $return .= $DBH->quote($row[$j]);
                    }
                } else {
                    $return .= 'NULL';
                }
                if ($j < ($num_fields - 1)) {
                    $return .= ',';
                }
            }
            $count++;
            if ($count < ($result->rowCount())) {
                $return .= "),";
            } else {
                $return .= ");";
            }
            if ($compression) {
                gzwrite($zp, $return);
            } else {
                fwrite($handle, $return);
            }
            $return = "";
        }
        $return = "\n\n-- ------------------------------------------------ \n\n";
        if ($compression) {
            gzwrite($zp, $return);
        } else {
            fwrite($handle, $return);
        }
        $return = "";
    }

    $error1 = $pstm2->errorInfo();
    $error2 = $pstm3->errorInfo();
    $error3 = $result->errorInfo();
    echo $error1[2];
    echo $error2[2];
    echo $error3[2];

    if ($compression) {
        gzclose($zp);
    } else {
        fclose($handle);
    }
}