Yii2 how to download database - database

Question

I want to download my database by clicking on a button. I have search around and found this code.
yii2 database download
I have added a action on my controller and added this modified code. I've removed database connection in the original code as I guess I don't need to make the connection again. I'm getting error at 'fetch_row()'. I tried Yii::$app->db->createCommand('fetch_row')but still getting error.
define('BACKUP_DIR', 'download/' ) ;
// Define Database Credentials
define('HOST', 'localhost' ) ;
define('USER', 'root' ) ;
define('PASSWORD', 'x24613rt' ) ;
define('DB_NAME', 'panthoibi' ) ;
$files = scandir(BACKUP_DIR);
if(count($files) > 2) {
for ($i=2; $i < count($files); $i++) {
unlink(BACKUP_DIR."/".$files[$i]);
}
}
/*
Define the filename for the sql file
If you plan to upload the file to Amazon's S3 service , use only lower-case letters
*/
$fileName = 'mysqlibackup--' . date('d-m-Y') . '#'.date('h.i.s').'.sql' ;
// Set execution time limit
if(function_exists('max_execution_time')) {
if( ini_get('max_execution_time') > 0 )
set_time_limit(0) ;
}
// Check if directory is already created and has the proper permissions
if (!file_exists(BACKUP_DIR)) mkdir(BACKUP_DIR , 0700) ;
if (!is_writable(BACKUP_DIR)) chmod(BACKUP_DIR , 0700) ;
// Create an ".htaccess" file , it will restrict direct accss to the backup-directory .
//$content = 'deny from all' ;
//$file = new SplFileObject(BACKUP_DIR . '/.htaccess', "w") ;
//$file->fwrite($content) ;
// Introduction information //
$return = "";
$return .= "--\n";
$return .= "-- A mysqli Backup System \n";
$return .= "--\n";
$return .= '-- Export created: ' . date("Y/m/d") . ' on ' . date("h:i") . "\n\n\n";
$return = "--\n";
$return .= "-- Database : " . DB_NAME . "\n";
$return .= "--\n";
$return .= "-- --------------------------------------------------\n";
$return .= "-- ---------------------------------------------------\n";
$return .= 'SET AUTOCOMMIT = 0 ;' ."\n" ;
$return .= 'SET FOREIGN_KEY_CHECKS=0 ;' ."\n" ;
$tables = array() ;
// Exploring what tables this database has
$result = Yii::$app->db->createCommand('SHOW TABLES');
// Cycle through "$result" and put content into an array
while ($row = $result->fetch_row())
$tables[] = $row[0] ;
// Cycle through each table
foreach($tables as $table)
{
// Get content of each table
$result = $mysqli->query('SELECT * FROM '. $table) ;
// Get number of fields (columns) of each table
$num_fields = $mysqli->field_count ;
// Add table information
$return .= "--\n" ;
$return .= '-- Tabel structure for table `' . $table . '`' . "\n" ;
$return .= "--\n" ;
$return.= 'DROP TABLE IF EXISTS `'.$table.'`;' . "\n" ;
// Get the table-shema
$shema = $mysqli->query('SHOW CREATE TABLE '.$table) ;
// Extract table shema
$tableshema = $shema->fetch_row() ;
// Append table-shema into code
$return.= $tableshema[1].";" . "\n\n" ;
// Cycle through each table-row
while($rowdata = $result->fetch_row())
{
// Prepare code that will insert data into table
$return .= 'INSERT INTO `'.$table .'` VALUES ( ' ;
// Extract data of each row
for($i=0; $i<$num_fields; $i++)
$return .= '"'.$rowdata[$i] . "\"," ;
// Let's remove the last comma
$return = substr("$return", 0, -1) ;
$return .= ");" ."\n" ;
}
$return .= "\n\n" ;
}
$return .= 'SET FOREIGN_KEY_CHECKS = 1 ; ' . "\n" ;
$return .= 'COMMIT ; ' . "\n" ;
$return .= 'SET AUTOCOMMIT = 1 ; ' . "\n" ;
//$file = file_put_contents($fileName , $return) ;
$zip = new ZipArchive() ;
$resOpen = $zip->open(BACKUP_DIR . '/' .$fileName.".zip" , ZIPARCHIVE::CREATE) ;
if( $resOpen )
$zip->addFromString( $fileName , "$return" ) ;
$zip->close() ;
$fileSize = $this->get_file_size_unit(filesize(BACKUP_DIR . "/". $fileName . '.zip')) ;

Answer 1

You are mixing Yii query command with mysqli command this don't work ..
eg:
You are using CreateCommand
// Exploring what tables this database has
$result = Yii::$app->db->createCommand('SHOW TABLES');
but don't execute .. you should try
$result = Yii::$app->db->createCommand('SHOW TABLES')->execute();
or
$result = Yii::$app->db->createCommand('SHOW TABLES')->queryOne();
or
$result = Yii::$app->db->createCommand('SHOW TABLES')->queryAll();
Then try take a look at the $result content eg:
var_dump($result);
Your $result content don't shoul be adapt for
$result->fetch_row()
but eventually you can iterate or manage the actual $result content with php function ..