/**
* The main loop triggered in step 5. Up here to keep it out of the way of the
* HTML. This walks every table in the db that was selected in step 3 and then
* walks every row and column replacing all occurences of a string with another.
* We split large tables into 50,000 row blocks when dealing with them to save
* on memmory consumption.
*
* @param mysql $connection The db connection object
* @param string $search What we want to replace
* @param string $replace What we want to replace it with.
* @param array $tables The tables we want to look at.
*
* @return array Collection of information gathered during the run.
*/
function icit_srdb_replacer($connection, $search = '', $replace = '', $tables = array())
{
global $guid, $exclude_cols;
$report = array('tables' => 0, 'rows' => 0, 'change' => 0, 'updates' => 0, 'start' => microtime(), 'end' => microtime(), 'errors' => array());
if (is_array($tables) && !empty($tables)) {
foreach ($tables as $table) {
$report['tables']++;
$columns = array();
// Get a list of columns in this table
$fields = mysql_query('DESCRIBE ' . $table, $connection);
while ($column = mysql_fetch_array($fields)) {
$columns[$column['Field']] = $column['Key'] == 'PRI' ? true : false;
}
// Count the number of rows we have in the table if large we'll split into blocks, This is a mod from Simon Wheatley
$row_count = mysql_query('SELECT COUNT(*) FROM ' . $table, $connection);
$rows_result = mysql_fetch_array($row_count);
$row_count = $rows_result[0];
if ($row_count == 0) {
continue;
}
$page_size = 50000;
$pages = ceil($row_count / $page_size);
for ($page = 0; $page < $pages; $page++) {
$current_row = 0;
$start = $page * $page_size;
$end = $start + $page_size;
// Grab the content of the table
$data = mysql_query(sprintf('SELECT * FROM %s LIMIT %d, %d', $table, $start, $end), $connection);
if (!$data) {
$report['errors'][] = mysql_error();
}
while ($row = mysql_fetch_array($data)) {
$report['rows']++;
// Increment the row counter
$current_row++;
$update_sql = array();
$where_sql = array();
$upd = false;
foreach ($columns as $column => $primary_key) {
if ($guid == 1 && in_array($column, $exclude_cols)) {
continue;
}
$edited_data = $data_to_fix = $row[$column];
// Run a search replace on the data that'll respect the serialisation.
$edited_data = recursive_unserialize_replace($search, $replace, $data_to_fix);
// Something was changed
if ($edited_data != $data_to_fix) {
$report['change']++;
$update_sql[] = $column . ' = "' . mysql_real_escape_string($edited_data) . '"';
$upd = true;
}
if ($primary_key) {
$where_sql[] = $column . ' = "' . mysql_real_escape_string($data_to_fix) . '"';
}
}
if ($upd && !empty($where_sql)) {
$sql = 'UPDATE ' . $table . ' SET ' . implode(', ', $update_sql) . ' WHERE ' . implode(' AND ', array_filter($where_sql));
$result = mysql_query($sql, $connection);
if (!$result) {
$report['errors'][] = mysql_error();
} else {
$report['updates']++;
}
} elseif ($upd) {
$report['errors'][] = sprintf('"%s" has no primary key, manual change needed on row %s.', $table, $current_row);
}
}
}
}
}
$report['end'] = microtime();
return $report;
}
/**
* Take a serialised array and unserialise it replacing elements as needed and
* unserialising any subordinate arrays and performing the replace on those too.
*
* @param string $from String we're looking to replace.
* @param string $to What we want it to be replaced with
* @param array $data Used to pass any subordinate arrays back to in.
* @param bool $serialised Does the array passed via $data need serialising.
*
* @return array The original array with all elements replaced as needed.
*/
function recursive_unserialize_replace( $from = '', $to = '', $data = '', $serialised = false ) {
// some unseriliased data cannot be re-serialised eg. SimpleXMLElements
try {
if ( is_string( $data ) && ( $unserialized = @unserialize( $data ) ) !== false ) {
$data = recursive_unserialize_replace( $from, $to, $unserialized, true );
}
elseif ( is_array( $data ) ) {
$_tmp = array( );
foreach ( $data as $key => $value ) {
$_tmp[ $key ] = recursive_unserialize_replace( $from, $to, $value, false );
}
$data = $_tmp;
unset( $_tmp );
}
// Submitted by Tina Matter
elseif ( is_object( $data ) ) {
$dataClass = get_class( $data );
$_tmp = new $dataClass( );
foreach ( $data as $key => $value ) {
$_tmp->$key = recursive_unserialize_replace( $from, $to, $value, false );
}
$data = $_tmp;
unset( $_tmp );
}
else {
if ( is_string( $data ) )
$data = str_replace( $from, $to, $data );
}
if ( $serialised )
return serialize( $data );
} catch( Exception $error ) {
}
return $data;
}
