3 * StatusNet, the distributed open-source microblogging tool
5 * Database schema utilities
9 * LICENCE: This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU Affero General Public License as published by
11 * the Free Software Foundation, either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Affero General Public License for more details.
19 * You should have received a copy of the GNU Affero General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 * @author Evan Prodromou <evan@status.net>
25 * @copyright 2009 StatusNet, Inc.
26 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
27 * @link http://status.net/
30 if (!defined('STATUSNET')) {
35 * Class representing the database schema
37 * A class representing the database schema. Can be used to
38 * manipulate the schema -- especially for plugins and upgrade
43 * @author Evan Prodromou <evan@status.net>
44 * @author Brenda Wallace <shiny@cpan.org>
45 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
46 * @link http://status.net/
49 class PgsqlSchema extends Schema
53 * Returns a TableDef object for the table
54 * in the schema with the given name.
56 * Throws an exception if the table is not found.
58 * @param string $name Name of the table to get
60 * @return TableDef tabledef for that table.
63 public function getTableDef($name)
65 $res = $this->conn->query("SELECT *, column_default as default, is_nullable as Null,
66 udt_name as Type, column_name AS Field from INFORMATION_SCHEMA.COLUMNS where table_name = '$name'");
68 if (PEAR::isError($res)) {
69 throw new Exception($res->getMessage());
75 $td->columns = array();
77 if ($res->numRows() == 0 ) {
78 throw new Exception('no such table'); //pretend to be the msyql error. yeah, this sucks.
82 while ($res->fetchInto($row, DB_FETCHMODE_ASSOC)) {
83 $cd = new ColumnDef();
85 $cd->name = $row['field'];
87 $packed = $row['type'];
89 if (preg_match('/^(\w+)\((\d+)\)$/', $packed, $match)) {
90 $cd->type = $match[1];
91 $cd->size = $match[2];
96 $cd->nullable = ($row['null'] == 'YES') ? true : false;
97 $cd->key = $row['Key'];
98 $cd->default = $row['default'];
99 $cd->extra = $row['Extra'];
101 $td->columns[] = $cd;
107 * Gets a ColumnDef object for a single column.
109 * Throws an exception if the table is not found.
111 * @param string $table name of the table
112 * @param string $column name of the column
114 * @return ColumnDef definition of the column or null
118 public function getColumnDef($table, $column)
120 $td = $this->getTableDef($table);
122 foreach ($td->columns as $cd) {
123 if ($cd->name == $column) {
132 * Creates a table with the given names and columns.
134 * @param string $name Name of the table
135 * @param array $columns Array of ColumnDef objects
138 * @return boolean success flag
141 public function createTable($name, $columns)
147 $sql = "CREATE TABLE $name (\n";
149 for ($i = 0; $i < count($columns); $i++) {
157 $sql .= $this->_columnSql($cd);
160 $uniques[] = $cd->name;
163 $primary[] = $cd->name;
166 $indices[] = $cd->name;
171 if (count($primary) > 0) { // it really should be...
172 $sql .= ",\n primary key (" . implode(',', $primary) . ")";
177 foreach ($indices as $i) {
178 $sql .= ",\nindex {$name}_{$i}_idx ($i)";
184 foreach ($uniques as $u) {
185 $sql .= "\n CREATE index {$name}_{$u}_idx ON {$name} ($u); ";
187 $res = $this->conn->query($sql);
189 if (PEAR::isError($res)) {
190 throw new Exception($res->getMessage(). ' SQL was '. $sql);
197 * Drops a table from the schema
199 * Throws an exception if the table is not found.
201 * @param string $name Name of the table to drop
203 * @return boolean success flag
206 public function dropTable($name)
208 $res = $this->conn->query("DROP TABLE $name");
210 if (PEAR::isError($res)) {
211 throw new Exception($res->getMessage());
218 * Translate the (mostly) mysql-ish column types into somethings more standard
219 * @param string column type
221 * @return string postgres happy column type
223 private function _columnTypeTranslation($type) {
225 'datetime' => 'timestamp',
227 if(!empty($map[$type])) {
234 * Adds an index to a table.
236 * If no name is provided, a name will be made up based
237 * on the table name and column names.
239 * Throws an exception on database error, esp. if the table
242 * @param string $table Name of the table
243 * @param array $columnNames Name of columns to index
244 * @param string $name (Optional) name of the index
246 * @return boolean success flag
249 public function createIndex($table, $columnNames, $name=null)
251 if (!is_array($columnNames)) {
252 $columnNames = array($columnNames);
256 $name = "$table_".implode("_", $columnNames)."_idx";
259 $res = $this->conn->query("ALTER TABLE $table ".
261 implode(",", $columnNames).")");
263 if (PEAR::isError($res)) {
264 throw new Exception($res->getMessage());
271 * Drops a named index from a table.
273 * @param string $table name of the table the index is on.
274 * @param string $name name of the index
276 * @return boolean success flag
279 public function dropIndex($table, $name)
281 $res = $this->conn->query("ALTER TABLE $table DROP INDEX $name");
283 if (PEAR::isError($res)) {
284 throw new Exception($res->getMessage());
291 * Adds a column to a table
293 * @param string $table name of the table
294 * @param ColumnDef $columndef Definition of the new
297 * @return boolean success flag
300 public function addColumn($table, $columndef)
302 $sql = "ALTER TABLE $table ADD COLUMN " . $this->_columnSql($columndef);
304 $res = $this->conn->query($sql);
306 if (PEAR::isError($res)) {
307 throw new Exception($res->getMessage());
314 * Modifies a column in the schema.
316 * The name must match an existing column and table.
318 * @param string $table name of the table
319 * @param ColumnDef $columndef new definition of the column.
321 * @return boolean success flag
324 public function modifyColumn($table, $columndef)
326 $sql = "ALTER TABLE $table MODIFY COLUMN " .
327 $this->_columnSql($columndef);
329 $res = $this->conn->query($sql);
331 if (PEAR::isError($res)) {
332 throw new Exception($res->getMessage());
339 * Drops a column from a table
341 * The name must match an existing column.
343 * @param string $table name of the table
344 * @param string $columnName name of the column to drop
346 * @return boolean success flag
349 public function dropColumn($table, $columnName)
351 $sql = "ALTER TABLE $table DROP COLUMN $columnName";
353 $res = $this->conn->query($sql);
355 if (PEAR::isError($res)) {
356 throw new Exception($res->getMessage());
363 * Ensures that a table exists with the given
364 * name and the given column definitions.
366 * If the table does not yet exist, it will
367 * create the table. If it does exist, it will
368 * alter the table to match the column definitions.
370 * @param string $tableName name of the table
371 * @param array $columns array of ColumnDef
372 * objects for the table
374 * @return boolean success flag
377 public function ensureTable($tableName, $columns)
379 // XXX: DB engine portability -> toilet
382 $td = $this->getTableDef($tableName);
384 } catch (Exception $e) {
385 if (preg_match('/no such table/', $e->getMessage())) {
386 return $this->createTable($tableName, $columns);
392 $cur = $this->_names($td->columns);
393 $new = $this->_names($columns);
395 $toadd = array_diff($new, $cur);
396 $todrop = array_diff($cur, $new);
397 $same = array_intersect($new, $cur);
399 foreach ($same as $m) {
400 $curCol = $this->_byName($td->columns, $m);
401 $newCol = $this->_byName($columns, $m);
404 if (!$newCol->equals($curCol)) {
406 // stop it detecting different types and trying to modify on every page request
407 // $tomod[] = $newCol->name;
410 if (count($toadd) + count($todrop) + count($tomod) == 0) {
415 // For efficiency, we want this all in one
416 // query, instead of using our methods.
420 foreach ($toadd as $columnName) {
421 $cd = $this->_byName($columns, $columnName);
423 $phrase[] = 'ADD COLUMN ' . $this->_columnSql($cd);
426 foreach ($todrop as $columnName) {
427 $phrase[] = 'DROP COLUMN ' . $columnName;
430 foreach ($tomod as $columnName) {
431 $cd = $this->_byName($columns, $columnName);
433 $phrase[] = 'MODIFY COLUMN ' . $this->_columnSql($cd);
436 $sql = 'ALTER TABLE ' . $tableName . ' ' . implode(', ', $phrase);
437 $res = $this->conn->query($sql);
439 if (PEAR::isError($res)) {
440 throw new Exception($res->getMessage());
447 * Returns the array of names from an array of
450 * @param array $cds array of ColumnDef objects
452 * @return array strings for name values
455 private function _names($cds)
459 foreach ($cds as $cd) {
460 $names[] = $cd->name;
467 * Get a ColumnDef from an array matching
470 * @param array $cds Array of ColumnDef objects
471 * @param string $name Name of the column
473 * @return ColumnDef matching item or null if no match.
476 private function _byName($cds, $name)
478 foreach ($cds as $cd) {
479 if ($cd->name == $name) {
488 * Return the proper SQL for creating or
491 * Appropriate for use in CREATE TABLE or
492 * ALTER TABLE statements.
494 * @param ColumnDef $cd column to create
496 * @return string correct SQL for that column
498 private function _columnSql($cd)
500 $sql = "{$cd->name} ";
501 $type = $this->_columnTypeTranslation($cd->type);
503 //handle those mysql enum fields that postgres doesn't support
504 if (preg_match('!^enum!', $type)) {
505 $allowed_values = preg_replace('!^enum!', '', $type);
506 $sql .= " text check ({$cd->name} in $allowed_values)";
509 if (!empty($cd->auto_increment)) {
513 if (!empty($cd->size)) {
514 $sql .= "{$type}({$cd->size}) ";
519 if (!empty($cd->default)) {
520 $sql .= "default {$cd->default} ";
522 $sql .= ($cd->nullable) ? "null " : "not null ";
525 if (!empty($cd->extra)) {
526 $sql .= "{$cd->extra} ";