<?php
/**
* StatusNet, the distributed open-source microblogging tool
*
* Database schema utilities
*
* PHP version 5
*
* LICENCE: This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* @category Database
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @copyright 2009 StatusNet, Inc.
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
if (!defined('STATUSNET')) {
exit(1);
}
/**
* Class representing the database schema
*
* A class representing the database schema. Can be used to
* manipulate the schema -- especially for plugins and upgrade
* utilities.
*
* @category Database
* @package StatusNet
* @author Evan Prodromou <evan@status.net>
* @author Brenda Wallace <shiny@cpan.org>
* @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
* @link http://status.net/
*/
class PgsqlSchema extends Schema
{
/**
* Returns a TableDef object for the table
* in the schema with the given name.
*
* Throws an exception if the table is not found.
*
* @param string $name Name of the table to get
*
* @return TableDef tabledef for that table.
*/
public function getTableDef($name)
{
$res = $this->conn->query("SELECT *, column_default as default, is_nullable as Null,
udt_name as Type, column_name AS Field from INFORMATION_SCHEMA.COLUMNS where table_name = '$name'");
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
$td = new TableDef();
$td->name = $name;
$td->columns = array();
if ($res->numRows() == 0 ) {
throw new Exception('no such table'); //pretend to be the msyql error. yeah, this sucks.
}
$row = array();
while ($res->fetchInto($row, DB_FETCHMODE_ASSOC)) {
$cd = new ColumnDef();
$cd->name = $row['field'];
$packed = $row['type'];
if (preg_match('/^(\w+)\((\d+)\)$/', $packed, $match)) {
$cd->type = $match[1];
$cd->size = $match[2];
} else {
$cd->type = $packed;
}
$cd->nullable = ($row['null'] == 'YES') ? true : false;
$cd->key = $row['Key'];
$cd->default = $row['default'];
$cd->extra = $row['Extra'];
$td->columns[] = $cd;
}
return $td;
}
/**
* Creates a table with the given names and columns.
*
* @param string $name Name of the table
* @param array $columns Array of ColumnDef objects
* for new table.
*
* @return boolean success flag
*/
public function createTable($name, $columns)
{
$uniques = array();
$primary = array();
$indices = array();
$onupdate = array();
$sql = "CREATE TABLE $name (\n";
for ($i = 0; $i < count($columns); $i++) {
$cd =& $columns[$i];
if ($i > 0) {
$sql .= ",\n";
}
$sql .= $this->_columnSql($cd);
switch ($cd->key) {
case 'UNI':
$uniques[] = $cd->name;
break;
case 'PRI':
$primary[] = $cd->name;
break;
case 'MUL':
$indices[] = $cd->name;
break;
}
}
if (count($primary) > 0) { // it really should be...
$sql .= ",\n PRIMARY KEY (" . implode(',', $primary) . ")";
}
$sql .= "); ";
foreach ($uniques as $u) {
$sql .= "\n CREATE index {$name}_{$u}_idx ON {$name} ($u); ";
}
foreach ($indices as $i) {
$sql .= "CREATE index {$name}_{$i}_idx ON {$name} ($i)";
}
$res = $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage(). ' SQL was '. $sql);
}
return true;
}
/**
* Translate the (mostly) mysql-ish column types into somethings more standard
* @param string column type
*
* @return string postgres happy column type
*/
private function _columnTypeTranslation($type) {
$map = array(
'datetime' => 'timestamp',
);
if(!empty($map[$type])) {
return $map[$type];
}
return $type;
}
/**
* Modifies a column in the schema.
*
* The name must match an existing column and table.
*
* @param string $table name of the table
* @param ColumnDef $columndef new definition of the column.
*
* @return boolean success flag
*/
public function modifyColumn($table, $columndef)
{
$sql = "ALTER TABLE $table ALTER COLUMN TYPE " .
$this->_columnSql($columndef);
$res = $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
/**
* Ensures that a table exists with the given
* name and the given column definitions.
*
* If the table does not yet exist, it will
* create the table. If it does exist, it will
* alter the table to match the column definitions.
*
* @param string $tableName name of the table
* @param array $columns array of ColumnDef
* objects for the table
*
* @return boolean success flag
*/
public function ensureTable($tableName, $columns)
{
// XXX: DB engine portability -> toilet
try {
$td = $this->getTableDef($tableName);
} catch (Exception $e) {
if (preg_match('/no such table/', $e->getMessage())) {
return $this->createTable($tableName, $columns);
} else {
throw $e;
}
}
$cur = $this->_names($td->columns);
$new = $this->_names($columns);
$toadd = array_diff($new, $cur);
$todrop = array_diff($cur, $new);
$same = array_intersect($new, $cur);
$tomod = array();
foreach ($same as $m) {
$curCol = $this->_byName($td->columns, $m);
$newCol = $this->_byName($columns, $m);
if (!$newCol->equals($curCol)) {
// BIG GIANT TODO!
// stop it detecting different types and trying to modify on every page request
// $tomod[] = $newCol->name;
}
}
if (count($toadd) + count($todrop) + count($tomod) == 0) {
// nothing to do
return true;
}
// For efficiency, we want this all in one
// query, instead of using our methods.
$phrase = array();
foreach ($toadd as $columnName) {
$cd = $this->_byName($columns, $columnName);
$phrase[] = 'ADD COLUMN ' . $this->_columnSql($cd);
}
foreach ($todrop as $columnName) {
$phrase[] = 'DROP COLUMN ' . $columnName;
}
foreach ($tomod as $columnName) {
$cd = $this->_byName($columns, $columnName);
/* brute force */
$phrase[] = 'DROP COLUMN ' . $columnName;
$phrase[] = 'ADD COLUMN ' . $this->_columnSql($cd);
}
$sql = 'ALTER TABLE ' . $tableName . ' ' . implode(', ', $phrase);
$res = $this->conn->query($sql);
if (PEAR::isError($res)) {
throw new Exception($res->getMessage());
}
return true;
}
/**
* Return the proper SQL for creating or
* altering a column.
*
* Appropriate for use in CREATE TABLE or
* ALTER TABLE statements.
*
* @param string $tableName
* @param array $tableDef
* @param string $columnName
* @param array $cd column to create
*
* @return string correct SQL for that column
*/
function columnSql($name, array $cd)
{
$line = array();
$line[] = parent::_columnSql($cd);
if ($table['foreign keys'][$name]) {
foreach ($table['foreign keys'][$name] as $foreignTable => $foreignColumn) {
$line[] = 'references';
$line[] = $this->quoteId($foreignTable);
$line[] = '(' . $this->quoteId($foreignColumn) . ')';
}
}
return implode(' ', $line);
}
function mapType($column)
{
$map = array('serial' => 'bigserial', // FIXME: creates the wrong name for the sequence for some internal sequence-lookup function, so better fix this to do the real 'create sequence' dance.
'numeric' => 'decimal',
'datetime' => 'timestamp',
'blob' => 'bytea');
$type = $column['type'];
if (isset($map[$type])) {
$type = $map[$type];
}
if (!empty($column['size'])) {
$size = $column['size'];
if ($type == 'integer' &&
in_array($size, array('small', 'big'))) {
$type = $size . 'int';
}
}
return $type;
}
// @fixme need name... :P
function typeAndSize($column)
{
if ($column['type'] == 'enum') {
$vals = array_map(array($this, 'quote'), $column['enum']);
return "text check ($name in " . implode(',', $vals) . ')';
} else {
return parent::typeAndSize($column);
}
}
}