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comparison includes/database.pgsql.inc @ 1:c1f4ac30525a 6.0

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Drupal 6.0
author Franck Deroche <webmaster@defr.org>
date Tue, 23 Dec 2008 14:28:28 +0100
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0:5a113a1c4740 1:c1f4ac30525a
1 <?php
2 // $Id: database.pgsql.inc,v 1.68.2.1 2008/02/07 10:17:26 goba Exp $
3
4 /**
5 * @file
6 * Database interface code for PostgreSQL database servers.
7 */
8
9 /**
10 * @ingroup database
11 * @{
12 */
13
14 /**
15 * Report database status.
16 */
17 function db_status_report() {
18 $t = get_t();
19
20 $version = db_version();
21
22 $form['pgsql'] = array(
23 'title' => $t('PostgreSQL database'),
24 'value' => $version,
25 );
26
27 if (version_compare($version, DRUPAL_MINIMUM_PGSQL) < 0) {
28 $form['pgsql']['severity'] = REQUIREMENT_ERROR;
29 $form['pgsql']['description'] = $t('Your PostgreSQL Server is too old. Drupal requires at least PostgreSQL %version.', array('%version' => DRUPAL_MINIMUM_PGSQL));
30 }
31
32 return $form;
33 }
34
35 /**
36 * Returns the version of the database server currently in use.
37 *
38 * @return Database server version
39 */
40 function db_version() {
41 return db_result(db_query("SHOW SERVER_VERSION"));
42 }
43
44 /**
45 * Initialize a database connection.
46 */
47 function db_connect($url) {
48 // Check if PostgreSQL support is present in PHP
49 if (!function_exists('pg_connect')) {
50 _db_error_page('Unable to use the PostgreSQL database because the PostgreSQL extension for PHP is not installed. Check your <code>php.ini</code> to see how you can enable it.');
51 }
52
53 $url = parse_url($url);
54 $conn_string = '';
55
56 // Decode url-encoded information in the db connection string
57 if (isset($url['user'])) {
58 $conn_string .= ' user='. urldecode($url['user']);
59 }
60 if (isset($url['pass'])) {
61 $conn_string .= ' password='. urldecode($url['pass']);
62 }
63 if (isset($url['host'])) {
64 $conn_string .= ' host='. urldecode($url['host']);
65 }
66 if (isset($url['path'])) {
67 $conn_string .= ' dbname='. substr(urldecode($url['path']), 1);
68 }
69 if (isset($url['port'])) {
70 $conn_string .= ' port='. urldecode($url['port']);
71 }
72
73 // pg_last_error() does not return a useful error message for database
74 // connection errors. We must turn on error tracking to get at a good error
75 // message, which will be stored in $php_errormsg.
76 $track_errors_previous = ini_get('track_errors');
77 ini_set('track_errors', 1);
78
79 $connection = @pg_connect($conn_string);
80 if (!$connection) {
81 require_once './includes/unicode.inc';
82 _db_error_page(decode_entities($php_errormsg));
83 }
84
85 // Restore error tracking setting
86 ini_set('track_errors', $track_errors_previous);
87
88 return $connection;
89 }
90
91 /**
92 * Runs a basic query in the active database.
93 *
94 * User-supplied arguments to the query should be passed in as separate
95 * parameters so that they can be properly escaped to avoid SQL injection
96 * attacks.
97 *
98 * @param $query
99 * A string containing an SQL query.
100 * @param ...
101 * A variable number of arguments which are substituted into the query
102 * using printf() syntax. Instead of a variable number of query arguments,
103 * you may also pass a single array containing the query arguments.
104 *
105 * Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
106 * in '') and %%.
107 *
108 * NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
109 * and TRUE values to decimal 1.
110 *
111 * @return
112 * A database query result resource, or FALSE if the query was not
113 * executed correctly.
114 */
115 function db_query($query) {
116 $args = func_get_args();
117 array_shift($args);
118 $query = db_prefix_tables($query);
119 if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
120 $args = $args[0];
121 }
122 _db_query_callback($args, TRUE);
123 $query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
124 return _db_query($query);
125 }
126
127 /**
128 * Helper function for db_query().
129 */
130 function _db_query($query, $debug = 0) {
131 global $active_db, $last_result, $queries;
132
133 if (variable_get('dev_query', 0)) {
134 list($usec, $sec) = explode(' ', microtime());
135 $timer = (float)$usec + (float)$sec;
136 }
137
138 $last_result = pg_query($active_db, $query);
139
140 if (variable_get('dev_query', 0)) {
141 $bt = debug_backtrace();
142 $query = $bt[2]['function'] ."\n". $query;
143 list($usec, $sec) = explode(' ', microtime());
144 $stop = (float)$usec + (float)$sec;
145 $diff = $stop - $timer;
146 $queries[] = array($query, $diff);
147 }
148
149 if ($debug) {
150 print '<p>query: '. $query .'<br />error:'. pg_last_error($active_db) .'</p>';
151 }
152
153 if ($last_result !== FALSE) {
154 return $last_result;
155 }
156 else {
157 // Indicate to drupal_error_handler that this is a database error.
158 ${DB_ERROR} = TRUE;
159 trigger_error(check_plain(pg_last_error($active_db) ."\nquery: ". $query), E_USER_WARNING);
160 return FALSE;
161 }
162 }
163
164 /**
165 * Fetch one result row from the previous query as an object.
166 *
167 * @param $result
168 * A database query result resource, as returned from db_query().
169 * @return
170 * An object representing the next row of the result, or FALSE. The attributes
171 * of this object are the table fields selected by the query.
172 */
173 function db_fetch_object($result) {
174 if ($result) {
175 return pg_fetch_object($result);
176 }
177 }
178
179 /**
180 * Fetch one result row from the previous query as an array.
181 *
182 * @param $result
183 * A database query result resource, as returned from db_query().
184 * @return
185 * An associative array representing the next row of the result, or FALSE.
186 * The keys of this object are the names of the table fields selected by the
187 * query, and the values are the field values for this result row.
188 */
189 function db_fetch_array($result) {
190 if ($result) {
191 return pg_fetch_assoc($result);
192 }
193 }
194
195 /**
196 * Return an individual result field from the previous query.
197 *
198 * Only use this function if exactly one field is being selected; otherwise,
199 * use db_fetch_object() or db_fetch_array().
200 *
201 * @param $result
202 * A database query result resource, as returned from db_query().
203 * @return
204 * The resulting field or FALSE.
205 */
206 function db_result($result) {
207 if ($result && pg_num_rows($result) > 0) {
208 $array = pg_fetch_row($result);
209 return $array[0];
210 }
211 return FALSE;
212 }
213
214 /**
215 * Determine whether the previous query caused an error.
216 */
217 function db_error() {
218 global $active_db;
219 return pg_last_error($active_db);
220 }
221
222 /**
223 * Returns the last insert id. This function is thread safe.
224 *
225 * @param $table
226 * The name of the table you inserted into.
227 * @param $field
228 * The name of the autoincrement field.
229 */
230 function db_last_insert_id($table, $field) {
231 return db_result(db_query("SELECT CURRVAL('{". db_escape_table($table) ."}_". db_escape_table($field) ."_seq')"));
232 }
233
234 /**
235 * Determine the number of rows changed by the preceding query.
236 */
237 function db_affected_rows() {
238 global $last_result;
239 return empty($last_result) ? 0 : pg_affected_rows($last_result);
240 }
241
242 /**
243 * Runs a limited-range query in the active database.
244 *
245 * Use this as a substitute for db_query() when a subset of the query
246 * is to be returned.
247 * User-supplied arguments to the query should be passed in as separate
248 * parameters so that they can be properly escaped to avoid SQL injection
249 * attacks.
250 *
251 * @param $query
252 * A string containing an SQL query.
253 * @param ...
254 * A variable number of arguments which are substituted into the query
255 * using printf() syntax. Instead of a variable number of query arguments,
256 * you may also pass a single array containing the query arguments.
257 * Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
258 * in '') and %%.
259 *
260 * NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
261 * and TRUE values to decimal 1.
262 *
263 * @param $from
264 * The first result row to return.
265 * @param $count
266 * The maximum number of result rows to return.
267 * @return
268 * A database query result resource, or FALSE if the query was not executed
269 * correctly.
270 */
271 function db_query_range($query) {
272 $args = func_get_args();
273 $count = array_pop($args);
274 $from = array_pop($args);
275 array_shift($args);
276
277 $query = db_prefix_tables($query);
278 if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
279 $args = $args[0];
280 }
281 _db_query_callback($args, TRUE);
282 $query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
283 $query .= ' LIMIT '. (int)$count .' OFFSET '. (int)$from;
284 return _db_query($query);
285 }
286
287 /**
288 * Runs a SELECT query and stores its results in a temporary table.
289 *
290 * Use this as a substitute for db_query() when the results need to stored
291 * in a temporary table. Temporary tables exist for the duration of the page
292 * request.
293 * User-supplied arguments to the query should be passed in as separate parameters
294 * so that they can be properly escaped to avoid SQL injection attacks.
295 *
296 * Note that if you need to know how many results were returned, you should do
297 * a SELECT COUNT(*) on the temporary table afterwards. db_affected_rows() does
298 * not give consistent result across different database types in this case.
299 *
300 * @param $query
301 * A string containing a normal SELECT SQL query.
302 * @param ...
303 * A variable number of arguments which are substituted into the query
304 * using printf() syntax. The query arguments can be enclosed in one
305 * array instead.
306 * Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
307 * in '') and %%.
308 *
309 * NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
310 * and TRUE values to decimal 1.
311 *
312 * @param $table
313 * The name of the temporary table to select into. This name will not be
314 * prefixed as there is no risk of collision.
315 * @return
316 * A database query result resource, or FALSE if the query was not executed
317 * correctly.
318 */
319 function db_query_temporary($query) {
320 $args = func_get_args();
321 $tablename = array_pop($args);
322 array_shift($args);
323
324 $query = preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE '. $tablename .' AS SELECT', db_prefix_tables($query));
325 if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
326 $args = $args[0];
327 }
328 _db_query_callback($args, TRUE);
329 $query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
330 return _db_query($query);
331 }
332
333 /**
334 * Returns a properly formatted Binary Large OBject value.
335 * In case of PostgreSQL encodes data for insert into bytea field.
336 *
337 * @param $data
338 * Data to encode.
339 * @return
340 * Encoded data.
341 */
342 function db_encode_blob($data) {
343 return "'". pg_escape_bytea($data) ."'";
344 }
345
346 /**
347 * Returns text from a Binary Large OBject value.
348 * In case of PostgreSQL decodes data after select from bytea field.
349 *
350 * @param $data
351 * Data to decode.
352 * @return
353 * Decoded data.
354 */
355 function db_decode_blob($data) {
356 return pg_unescape_bytea($data);
357 }
358
359 /**
360 * Prepare user input for use in a database query, preventing SQL injection attacks.
361 * Note: This function requires PostgreSQL 7.2 or later.
362 */
363 function db_escape_string($text) {
364 return pg_escape_string($text);
365 }
366
367 /**
368 * Lock a table.
369 * This function automatically starts a transaction.
370 */
371 function db_lock_table($table) {
372 db_query('BEGIN; LOCK TABLE {'. db_escape_table($table) .'} IN EXCLUSIVE MODE');
373 }
374
375 /**
376 * Unlock all locked tables.
377 * This function automatically commits a transaction.
378 */
379 function db_unlock_tables() {
380 db_query('COMMIT');
381 }
382
383 /**
384 * Check if a table exists.
385 */
386 function db_table_exists($table) {
387 return (bool) db_result(db_query("SELECT COUNT(*) FROM pg_class WHERE relname = '{". db_escape_table($table) ."}'"));
388 }
389
390 /**
391 * Check if a column exists in the given table.
392 */
393 function db_column_exists($table, $column) {
394 return (bool) db_result(db_query("SELECT COUNT(pg_attribute.attname) FROM pg_class, pg_attribute WHERE pg_attribute.attrelid = pg_class.oid AND pg_class.relname = '{". db_escape_table($table) ."}' AND attname = '". db_escape_table($column) ."'"));
395 }
396
397 /**
398 * Verify if the database is set up correctly.
399 */
400 function db_check_setup() {
401 $t = get_t();
402
403 $encoding = db_result(db_query('SHOW server_encoding'));
404 if (!in_array(strtolower($encoding), array('unicode', 'utf8'))) {
405 drupal_set_message($t('Your PostgreSQL database is set up with the wrong character encoding (%encoding). It is possible it will not work as expected. It is advised to recreate it with UTF-8/Unicode encoding. More information can be found in the <a href="@url">PostgreSQL documentation</a>.', array('%encoding' => $encoding, '@url' => 'http://www.postgresql.org/docs/7.4/interactive/multibyte.html')), 'status');
406 }
407 }
408
409 /**
410 * Wraps the given table.field entry with a DISTINCT(). The wrapper is added to
411 * the SELECT list entry of the given query and the resulting query is returned.
412 * This function only applies the wrapper if a DISTINCT doesn't already exist in
413 * the query.
414 *
415 * @param $table Table containing the field to set as DISTINCT
416 * @param $field Field to set as DISTINCT
417 * @param $query Query to apply the wrapper to
418 * @return SQL query with the DISTINCT wrapper surrounding the given table.field.
419 */
420 function db_distinct_field($table, $field, $query) {
421 $field_to_select = 'DISTINCT ON ('. $table .'.'. $field .") $table.$field";
422 // (?<!text) is a negative look-behind (no need to rewrite queries that already use DISTINCT).
423 $query = preg_replace('/(SELECT.*)(?:'. $table .'\.|\s)(?<!DISTINCT\()(?<!DISTINCT\('. $table .'\.)'. $field .'(.*FROM )/AUsi', '\1 '. $field_to_select .'\2', $query);
424 $query = preg_replace('/(ORDER BY )(?!'. $table .'\.'. $field .')/', '\1'."$table.$field, ", $query);
425 return $query;
426 }
427
428 /**
429 * @} End of "ingroup database".
430 */
431
432 /**
433 * @ingroup schemaapi
434 * @{
435 */
436
437 /**
438 * This maps a generic data type in combination with its data size
439 * to the engine-specific data type.
440 */
441 function db_type_map() {
442 // Put :normal last so it gets preserved by array_flip. This makes
443 // it much easier for modules (such as schema.module) to map
444 // database types back into schema types.
445 $map = array(
446 'varchar:normal' => 'varchar',
447 'char:normal' => 'character',
448
449 'text:tiny' => 'text',
450 'text:small' => 'text',
451 'text:medium' => 'text',
452 'text:big' => 'text',
453 'text:normal' => 'text',
454
455 'int:tiny' => 'smallint',
456 'int:small' => 'smallint',
457 'int:medium' => 'int',
458 'int:big' => 'bigint',
459 'int:normal' => 'int',
460
461 'float:tiny' => 'real',
462 'float:small' => 'real',
463 'float:medium' => 'real',
464 'float:big' => 'double precision',
465 'float:normal' => 'real',
466
467 'numeric:normal' => 'numeric',
468
469 'blob:big' => 'bytea',
470 'blob:normal' => 'bytea',
471
472 'datetime:normal' => 'timestamp',
473
474 'serial:tiny' => 'serial',
475 'serial:small' => 'serial',
476 'serial:medium' => 'serial',
477 'serial:big' => 'bigserial',
478 'serial:normal' => 'serial',
479 );
480 return $map;
481 }
482
483 /**
484 * Generate SQL to create a new table from a Drupal schema definition.
485 *
486 * @param $name
487 * The name of the table to create.
488 * @param $table
489 * A Schema API table definition array.
490 * @return
491 * An array of SQL statements to create the table.
492 */
493 function db_create_table_sql($name, $table) {
494 $sql_fields = array();
495 foreach ($table['fields'] as $field_name => $field) {
496 $sql_fields[] = _db_create_field_sql($field_name, _db_process_field($field));
497 }
498
499 $sql_keys = array();
500 if (isset($table['primary key']) && is_array($table['primary key'])) {
501 $sql_keys[] = 'PRIMARY KEY ('. implode(', ', $table['primary key']) .')';
502 }
503 if (isset($table['unique keys']) && is_array($table['unique keys'])) {
504 foreach ($table['unique keys'] as $key_name => $key) {
505 $sql_keys[] = 'CONSTRAINT {'. $name .'}_'. $key_name .'_key UNIQUE ('. implode(', ', $key) .')';
506 }
507 }
508
509 $sql = "CREATE TABLE {". $name ."} (\n\t";
510 $sql .= implode(",\n\t", $sql_fields);
511 if (count($sql_keys) > 0) {
512 $sql .= ",\n\t";
513 }
514 $sql .= implode(",\n\t", $sql_keys);
515 $sql .= "\n)";
516 $statements[] = $sql;
517
518 if (isset($table['indexes']) && is_array($table['indexes'])) {
519 foreach ($table['indexes'] as $key_name => $key) {
520 $statements[] = _db_create_index_sql($name, $key_name, $key);
521 }
522 }
523
524 return $statements;
525 }
526
527 function _db_create_index_sql($table, $name, $fields) {
528 $query = 'CREATE INDEX {'. $table .'}_'. $name .'_idx ON {'. $table .'} (';
529 $query .= _db_create_key_sql($fields) .')';
530 return $query;
531 }
532
533 function _db_create_key_sql($fields) {
534 $ret = array();
535 foreach ($fields as $field) {
536 if (is_array($field)) {
537 $ret[] = 'substr('. $field[0] .', 1, '. $field[1] .')';
538 }
539 else {
540 $ret[] = $field;
541 }
542 }
543 return implode(', ', $ret);
544 }
545
546 function _db_create_keys(&$ret, $table, $new_keys) {
547 if (isset($new_keys['primary key'])) {
548 db_add_primary_key($ret, $table, $new_keys['primary key']);
549 }
550 if (isset($new_keys['unique keys'])) {
551 foreach ($new_keys['unique keys'] as $name => $fields) {
552 db_add_unique_key($ret, $table, $name, $fields);
553 }
554 }
555 if (isset($new_keys['indexes'])) {
556 foreach ($new_keys['indexes'] as $name => $fields) {
557 db_add_index($ret, $table, $name, $fields);
558 }
559 }
560 }
561
562 /**
563 * Set database-engine specific properties for a field.
564 *
565 * @param $field
566 * A field description array, as specified in the schema documentation.
567 */
568 function _db_process_field($field) {
569 if (!isset($field['size'])) {
570 $field['size'] = 'normal';
571 }
572 // Set the correct database-engine specific datatype.
573 if (!isset($field['pgsql_type'])) {
574 $map = db_type_map();
575 $field['pgsql_type'] = $map[$field['type'] .':'. $field['size']];
576 }
577 if ($field['type'] == 'serial') {
578 unset($field['not null']);
579 }
580 return $field;
581 }
582
583 /**
584 * Create an SQL string for a field to be used in table creation or alteration.
585 *
586 * Before passing a field out of a schema definition into this function it has
587 * to be processed by _db_process_field().
588 *
589 * @param $name
590 * Name of the field.
591 * @param $spec
592 * The field specification, as per the schema data structure format.
593 */
594 function _db_create_field_sql($name, $spec) {
595 $sql = $name .' '. $spec['pgsql_type'];
596
597 if ($spec['type'] == 'serial') {
598 unset($spec['not null']);
599 }
600 if (!empty($spec['unsigned'])) {
601 if ($spec['type'] == 'serial') {
602 $sql .= " CHECK ($name >= 0)";
603 }
604 else {
605 $sql .= '_unsigned';
606 }
607 }
608
609 if (!empty($spec['length'])) {
610 $sql .= '('. $spec['length'] .')';
611 }
612 elseif (isset($spec['precision']) && isset($spec['scale'])) {
613 $sql .= '('. $spec['precision'] .', '. $spec['scale'] .')';
614 }
615
616 if (isset($spec['not null']) && $spec['not null']) {
617 $sql .= ' NOT NULL';
618 }
619 if (isset($spec['default'])) {
620 $default = is_string($spec['default']) ? "'". $spec['default'] ."'" : $spec['default'];
621 $sql .= " default $default";
622 }
623
624 return $sql;
625 }
626
627 /**
628 * Rename a table.
629 *
630 * @param $ret
631 * Array to which query results will be added.
632 * @param $table
633 * The table to be renamed.
634 * @param $new_name
635 * The new name for the table.
636 */
637 function db_rename_table(&$ret, $table, $new_name) {
638 $ret[] = update_sql('ALTER TABLE {'. $table .'} RENAME TO {'. $new_name .'}');
639 }
640
641 /**
642 * Drop a table.
643 *
644 * @param $ret
645 * Array to which query results will be added.
646 * @param $table
647 * The table to be dropped.
648 */
649 function db_drop_table(&$ret, $table) {
650 $ret[] = update_sql('DROP TABLE {'. $table .'}');
651 }
652
653 /**
654 * Add a new field to a table.
655 *
656 * @param $ret
657 * Array to which query results will be added.
658 * @param $table
659 * Name of the table to be altered.
660 * @param $field
661 * Name of the field to be added.
662 * @param $spec
663 * The field specification array, as taken from a schema definition.
664 * The specification may also contain the key 'initial', the newly
665 * created field will be set to the value of the key in all rows.
666 * This is most useful for creating NOT NULL columns with no default
667 * value in existing tables.
668 * @param $keys_new
669 * Optional keys and indexes specification to be created on the
670 * table along with adding the field. The format is the same as a
671 * table specification but without the 'fields' element. If you are
672 * adding a type 'serial' field, you MUST specify at least one key
673 * or index including it in this array. @see db_change_field for more
674 * explanation why.
675 */
676 function db_add_field(&$ret, $table, $field, $spec, $new_keys = array()) {
677 $fixnull = FALSE;
678 if (!empty($spec['not null']) && !isset($spec['default'])) {
679 $fixnull = TRUE;
680 $spec['not null'] = FALSE;
681 }
682 $query = 'ALTER TABLE {'. $table .'} ADD COLUMN ';
683 $query .= _db_create_field_sql($field, _db_process_field($spec));
684 $ret[] = update_sql($query);
685 if (isset($spec['initial'])) {
686 // All this because update_sql does not support %-placeholders.
687 $sql = 'UPDATE {'. $table .'} SET '. $field .' = '. db_type_placeholder($spec['type']);
688 $result = db_query($sql, $spec['initial']);
689 $ret[] = array('success' => $result !== FALSE, 'query' => check_plain($sql .' ('. $spec['initial'] .')'));
690 }
691 if ($fixnull) {
692 $ret[] = update_sql("ALTER TABLE {". $table ."} ALTER $field SET NOT NULL");
693 }
694 if (isset($new_keys)) {
695 _db_create_keys($ret, $table, $new_keys);
696 }
697 }
698
699 /**
700 * Drop a field.
701 *
702 * @param $ret
703 * Array to which query results will be added.
704 * @param $table
705 * The table to be altered.
706 * @param $field
707 * The field to be dropped.
708 */
709 function db_drop_field(&$ret, $table, $field) {
710 $ret[] = update_sql('ALTER TABLE {'. $table .'} DROP COLUMN '. $field);
711 }
712
713 /**
714 * Set the default value for a field.
715 *
716 * @param $ret
717 * Array to which query results will be added.
718 * @param $table
719 * The table to be altered.
720 * @param $field
721 * The field to be altered.
722 * @param $default
723 * Default value to be set. NULL for 'default NULL'.
724 */
725 function db_field_set_default(&$ret, $table, $field, $default) {
726 if ($default == NULL) {
727 $default = 'NULL';
728 }
729 else {
730 $default = is_string($default) ? "'$default'" : $default;
731 }
732
733 $ret[] = update_sql('ALTER TABLE {'. $table .'} ALTER COLUMN '. $field .' SET DEFAULT '. $default);
734 }
735
736 /**
737 * Set a field to have no default value.
738 *
739 * @param $ret
740 * Array to which query results will be added.
741 * @param $table
742 * The table to be altered.
743 * @param $field
744 * The field to be altered.
745 */
746 function db_field_set_no_default(&$ret, $table, $field) {
747 $ret[] = update_sql('ALTER TABLE {'. $table .'} ALTER COLUMN '. $field .' DROP DEFAULT');
748 }
749
750 /**
751 * Add a primary key.
752 *
753 * @param $ret
754 * Array to which query results will be added.
755 * @param $table
756 * The table to be altered.
757 * @param $fields
758 * Fields for the primary key.
759 */
760 function db_add_primary_key(&$ret, $table, $fields) {
761 $ret[] = update_sql('ALTER TABLE {'. $table .'} ADD PRIMARY KEY ('.
762 implode(',', $fields) .')');
763 }
764
765 /**
766 * Drop the primary key.
767 *
768 * @param $ret
769 * Array to which query results will be added.
770 * @param $table
771 * The table to be altered.
772 */
773 function db_drop_primary_key(&$ret, $table) {
774 $ret[] = update_sql('ALTER TABLE {'. $table .'} DROP CONSTRAINT {'. $table .'}_pkey');
775 }
776
777 /**
778 * Add a unique key.
779 *
780 * @param $ret
781 * Array to which query results will be added.
782 * @param $table
783 * The table to be altered.
784 * @param $name
785 * The name of the key.
786 * @param $fields
787 * An array of field names.
788 */
789 function db_add_unique_key(&$ret, $table, $name, $fields) {
790 $name = '{'. $table .'}_'. $name .'_key';
791 $ret[] = update_sql('ALTER TABLE {'. $table .'} ADD CONSTRAINT '.
792 $name .' UNIQUE ('. implode(',', $fields) .')');
793 }
794
795 /**
796 * Drop a unique key.
797 *
798 * @param $ret
799 * Array to which query results will be added.
800 * @param $table
801 * The table to be altered.
802 * @param $name
803 * The name of the key.
804 */
805 function db_drop_unique_key(&$ret, $table, $name) {
806 $name = '{'. $table .'}_'. $name .'_key';
807 $ret[] = update_sql('ALTER TABLE {'. $table .'} DROP CONSTRAINT '. $name);
808 }
809
810 /**
811 * Add an index.
812 *
813 * @param $ret
814 * Array to which query results will be added.
815 * @param $table
816 * The table to be altered.
817 * @param $name
818 * The name of the index.
819 * @param $fields
820 * An array of field names.
821 */
822 function db_add_index(&$ret, $table, $name, $fields) {
823 $ret[] = update_sql(_db_create_index_sql($table, $name, $fields));
824 }
825
826 /**
827 * Drop an index.
828 *
829 * @param $ret
830 * Array to which query results will be added.
831 * @param $table
832 * The table to be altered.
833 * @param $name
834 * The name of the index.
835 */
836 function db_drop_index(&$ret, $table, $name) {
837 $name = '{'. $table .'}_'. $name .'_idx';
838 $ret[] = update_sql('DROP INDEX '. $name);
839 }
840
841 /**
842 * Change a field definition.
843 *
844 * IMPORTANT NOTE: To maintain database portability, you have to explicitly
845 * recreate all indices and primary keys that are using the changed field.
846 *
847 * That means that you have to drop all affected keys and indexes with
848 * db_drop_{primary_key,unique_key,index}() before calling db_change_field().
849 * To recreate the keys and indices, pass the key definitions as the
850 * optional $new_keys argument directly to db_change_field().
851 *
852 * For example, suppose you have:
853 * @code
854 * $schema['foo'] = array(
855 * 'fields' => array(
856 * 'bar' => array('type' => 'int', 'not null' => TRUE)
857 * ),
858 * 'primary key' => array('bar')
859 * );
860 * @endcode
861 * and you want to change foo.bar to be type serial, leaving it as the
862 * primary key. The correct sequence is:
863 * @code
864 * db_drop_primary_key($ret, 'foo');
865 * db_change_field($ret, 'foo', 'bar', 'bar',
866 * array('type' => 'serial', 'not null' => TRUE),
867 * array('primary key' => array('bar')));
868 * @endcode
869 *
870 * The reasons for this are due to the different database engines:
871 *
872 * On PostgreSQL, changing a field definition involves adding a new field
873 * and dropping an old one which* causes any indices, primary keys and
874 * sequences (from serial-type fields) that use the changed field to be dropped.
875 *
876 * On MySQL, all type 'serial' fields must be part of at least one key
877 * or index as soon as they are created. You cannot use
878 * db_add_{primary_key,unique_key,index}() for this purpose because
879 * the ALTER TABLE command will fail to add the column without a key
880 * or index specification. The solution is to use the optional
881 * $new_keys argument to create the key or index at the same time as
882 * field.
883 *
884 * You could use db_add_{primary_key,unique_key,index}() in all cases
885 * unless you are converting a field to be type serial. You can use
886 * the $new_keys argument in all cases.
887 *
888 * @param $ret
889 * Array to which query results will be added.
890 * @param $table
891 * Name of the table.
892 * @param $field
893 * Name of the field to change.
894 * @param $field_new
895 * New name for the field (set to the same as $field if you don't want to change the name).
896 * @param $spec
897 * The field specification for the new field.
898 * @param $new_keys
899 * Optional keys and indexes specification to be created on the
900 * table along with changing the field. The format is the same as a
901 * table specification but without the 'fields' element.
902 */
903 function db_change_field(&$ret, $table, $field, $field_new, $spec, $new_keys = array()) {
904 $ret[] = update_sql("ALTER TABLE {". $table ."} RENAME $field TO ". $field ."_old");
905 $not_null = isset($spec['not null']) ? $spec['not null'] : FALSE;
906 unset($spec['not null']);
907
908 db_add_field($ret, $table, "$field_new", $spec);
909
910 $ret[] = update_sql("UPDATE {". $table ."} SET $field_new = ". $field ."_old");
911
912 if ($not_null) {
913 $ret[] = update_sql("ALTER TABLE {". $table ."} ALTER $field_new SET NOT NULL");
914 }
915
916 db_drop_field($ret, $table, $field .'_old');
917
918 if (isset($new_keys)) {
919 _db_create_keys($ret, $table, $new_keys);
920 }
921 }
922
923 /**
924 * @} End of "ingroup schemaapi".
925 */
926