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<?php
// $Id: database.pgsql.inc,v 1.68.2.1 2008/02/07 10:17:26 goba Exp $
/**
* @file
* Database interface code for PostgreSQL database servers.
*/
/**
* @ingroup database
* @{
*/
/**
* Report database status.
*/
function db_status_report() {
$t = get_t();
$version = db_version();
$form['pgsql'] = array(
'title' => $t('PostgreSQL database'),
'value' => $version,
);
if (version_compare($version, DRUPAL_MINIMUM_PGSQL) < 0) {
$form['pgsql']['severity'] = REQUIREMENT_ERROR;
$form['pgsql']['description'] = $t('Your PostgreSQL Server is too old. Drupal requires at least PostgreSQL %version.', array('%version' => DRUPAL_MINIMUM_PGSQL));
}
return $form;
}
/**
* Returns the version of the database server currently in use.
*
* @return Database server version
*/
function db_version() {
return db_result(db_query("SHOW SERVER_VERSION"));
}
/**
* Initialize a database connection.
*/
function db_connect($url) {
// Check if PostgreSQL support is present in PHP
if (!function_exists('pg_connect')) {
_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.');
}
$url = parse_url($url);
$conn_string = '';
// Decode url-encoded information in the db connection string
if (isset($url['user'])) {
$conn_string .= ' user='. urldecode($url['user']);
}
if (isset($url['pass'])) {
$conn_string .= ' password='. urldecode($url['pass']);
}
if (isset($url['host'])) {
$conn_string .= ' host='. urldecode($url['host']);
}
if (isset($url['path'])) {
$conn_string .= ' dbname='. substr(urldecode($url['path']), 1);
}
if (isset($url['port'])) {
$conn_string .= ' port='. urldecode($url['port']);
}
// pg_last_error() does not return a useful error message for database
// connection errors. We must turn on error tracking to get at a good error
// message, which will be stored in $php_errormsg.
$track_errors_previous = ini_get('track_errors');
ini_set('track_errors', 1);
$connection = @pg_connect($conn_string);
if (!$connection) {
require_once './includes/unicode.inc';
_db_error_page(decode_entities($php_errormsg));
}
// Restore error tracking setting
ini_set('track_errors', $track_errors_previous);
return $connection;
}
/**
* Runs a basic query in the active database.
*
* User-supplied arguments to the query should be passed in as separate
* parameters so that they can be properly escaped to avoid SQL injection
* attacks.
*
* @param $query
* A string containing an SQL query.
* @param ...
* A variable number of arguments which are substituted into the query
* using printf() syntax. Instead of a variable number of query arguments,
* you may also pass a single array containing the query arguments.
*
* Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
* in '') and %%.
*
* NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
* and TRUE values to decimal 1.
*
* @return
* A database query result resource, or FALSE if the query was not
* executed correctly.
*/
function db_query($query) {
$args = func_get_args();
array_shift($args);
$query = db_prefix_tables($query);
if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
$args = $args[0];
}
_db_query_callback($args, TRUE);
$query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
return _db_query($query);
}
/**
* Helper function for db_query().
*/
function _db_query($query, $debug = 0) {
global $active_db, $last_result, $queries;
if (variable_get('dev_query', 0)) {
list($usec, $sec) = explode(' ', microtime());
$timer = (float)$usec + (float)$sec;
}
$last_result = pg_query($active_db, $query);
if (variable_get('dev_query', 0)) {
$bt = debug_backtrace();
$query = $bt[2]['function'] ."\n". $query;
list($usec, $sec) = explode(' ', microtime());
$stop = (float)$usec + (float)$sec;
$diff = $stop - $timer;
$queries[] = array($query, $diff);
}
if ($debug) {
print '<p>query: '. $query .'<br />error:'. pg_last_error($active_db) .'</p>';
}
if ($last_result !== FALSE) {
return $last_result;
}
else {
// Indicate to drupal_error_handler that this is a database error.
${DB_ERROR} = TRUE;
trigger_error(check_plain(pg_last_error($active_db) ."\nquery: ". $query), E_USER_WARNING);
return FALSE;
}
}
/**
* Fetch one result row from the previous query as an object.
*
* @param $result
* A database query result resource, as returned from db_query().
* @return
* An object representing the next row of the result, or FALSE. The attributes
* of this object are the table fields selected by the query.
*/
function db_fetch_object($result) {
if ($result) {
return pg_fetch_object($result);
}
}
/**
* Fetch one result row from the previous query as an array.
*
* @param $result
* A database query result resource, as returned from db_query().
* @return
* An associative array representing the next row of the result, or FALSE.
* The keys of this object are the names of the table fields selected by the
* query, and the values are the field values for this result row.
*/
function db_fetch_array($result) {
if ($result) {
return pg_fetch_assoc($result);
}
}
/**
* Return an individual result field from the previous query.
*
* Only use this function if exactly one field is being selected; otherwise,
* use db_fetch_object() or db_fetch_array().
*
* @param $result
* A database query result resource, as returned from db_query().
* @return
* The resulting field or FALSE.
*/
function db_result($result) {
if ($result && pg_num_rows($result) > 0) {
$array = pg_fetch_row($result);
return $array[0];
}
return FALSE;
}
/**
* Determine whether the previous query caused an error.
*/
function db_error() {
global $active_db;
return pg_last_error($active_db);
}
/**
* Returns the last insert id. This function is thread safe.
*
* @param $table
* The name of the table you inserted into.
* @param $field
* The name of the autoincrement field.
*/
function db_last_insert_id($table, $field) {
return db_result(db_query("SELECT CURRVAL('{". db_escape_table($table) ."}_". db_escape_table($field) ."_seq')"));
}
/**
* Determine the number of rows changed by the preceding query.
*/
function db_affected_rows() {
global $last_result;
return empty($last_result) ? 0 : pg_affected_rows($last_result);
}
/**
* Runs a limited-range query in the active database.
*
* Use this as a substitute for db_query() when a subset of the query
* is to be returned.
* User-supplied arguments to the query should be passed in as separate
* parameters so that they can be properly escaped to avoid SQL injection
* attacks.
*
* @param $query
* A string containing an SQL query.
* @param ...
* A variable number of arguments which are substituted into the query
* using printf() syntax. Instead of a variable number of query arguments,
* you may also pass a single array containing the query arguments.
* Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
* in '') and %%.
*
* NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
* and TRUE values to decimal 1.
*
* @param $from
* The first result row to return.
* @param $count
* The maximum number of result rows to return.
* @return
* A database query result resource, or FALSE if the query was not executed
* correctly.
*/
function db_query_range($query) {
$args = func_get_args();
$count = array_pop($args);
$from = array_pop($args);
array_shift($args);
$query = db_prefix_tables($query);
if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
$args = $args[0];
}
_db_query_callback($args, TRUE);
$query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
$query .= ' LIMIT '. (int)$count .' OFFSET '. (int)$from;
return _db_query($query);
}
/**
* Runs a SELECT query and stores its results in a temporary table.
*
* Use this as a substitute for db_query() when the results need to stored
* in a temporary table. Temporary tables exist for the duration of the page
* request.
* User-supplied arguments to the query should be passed in as separate parameters
* so that they can be properly escaped to avoid SQL injection attacks.
*
* Note that if you need to know how many results were returned, you should do
* a SELECT COUNT(*) on the temporary table afterwards. db_affected_rows() does
* not give consistent result across different database types in this case.
*
* @param $query
* A string containing a normal SELECT SQL query.
* @param ...
* A variable number of arguments which are substituted into the query
* using printf() syntax. The query arguments can be enclosed in one
* array instead.
* Valid %-modifiers are: %s, %d, %f, %b (binary data, do not enclose
* in '') and %%.
*
* NOTE: using this syntax will cast NULL and FALSE values to decimal 0,
* and TRUE values to decimal 1.
*
* @param $table
* The name of the temporary table to select into. This name will not be
* prefixed as there is no risk of collision.
* @return
* A database query result resource, or FALSE if the query was not executed
* correctly.
*/
function db_query_temporary($query) {
$args = func_get_args();
$tablename = array_pop($args);
array_shift($args);
$query = preg_replace('/^SELECT/i', 'CREATE TEMPORARY TABLE '. $tablename .' AS SELECT', db_prefix_tables($query));
if (isset($args[0]) and is_array($args[0])) { // 'All arguments in one array' syntax
$args = $args[0];
}
_db_query_callback($args, TRUE);
$query = preg_replace_callback(DB_QUERY_REGEXP, '_db_query_callback', $query);
return _db_query($query);
}
/**
* Returns a properly formatted Binary Large OBject value.
* In case of PostgreSQL encodes data for insert into bytea field.
*
* @param $data
* Data to encode.
* @return
* Encoded data.
*/
function db_encode_blob($data) {
return "'". pg_escape_bytea($data) ."'";
}
/**
* Returns text from a Binary Large OBject value.
* In case of PostgreSQL decodes data after select from bytea field.
*
* @param $data
* Data to decode.
* @return
* Decoded data.
*/
function db_decode_blob($data) {
return pg_unescape_bytea($data);
}
/**
* Prepare user input for use in a database query, preventing SQL injection attacks.
* Note: This function requires PostgreSQL 7.2 or later.
*/
function db_escape_string($text) {
return pg_escape_string($text);
}
/**
* Lock a table.
* This function automatically starts a transaction.
*/
function db_lock_table($table) {
db_query('BEGIN; LOCK TABLE {'. db_escape_table($table) .'} IN EXCLUSIVE MODE');
}
/**
* Unlock all locked tables.
* This function automatically commits a transaction.
*/
function db_unlock_tables() {
db_query('COMMIT');
}
/**
* Check if a table exists.
*/
function db_table_exists($table) {
return (bool) db_result(db_query("SELECT COUNT(*) FROM pg_class WHERE relname = '{". db_escape_table($table) ."}'"));
}
/**
* Check if a column exists in the given table.
*/
function db_column_exists($table, $column) {
return (bool) db_result(db_query("SELECT COUNT(pg_attribute.attname) FROM pg_class, pg_attribute WHERE pg_attribute.attrelid = pg_class.oid AND pg_class.relname = '{". db_escape_table($table) ."}' AND attname = '". db_escape_table($column) ."'"));
}
/**
* Verify if the database is set up correctly.
*/
function db_check_setup() {
$t = get_t();
$encoding = db_result(db_query('SHOW server_encoding'));
if (!in_array(strtolower($encoding), array('unicode', 'utf8'))) {
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');
}
}
/**
* Wraps the given table.field entry with a DISTINCT(). The wrapper is added to
* the SELECT list entry of the given query and the resulting query is returned.
* This function only applies the wrapper if a DISTINCT doesn't already exist in
* the query.
*
* @param $table Table containing the field to set as DISTINCT
* @param $field Field to set as DISTINCT
* @param $query Query to apply the wrapper to
* @return SQL query with the DISTINCT wrapper surrounding the given table.field.
*/
function db_distinct_field($table, $field, $query) {
$field_to_select = 'DISTINCT ON ('. $table .'.'. $field .") $table.$field";
// (?<!text) is a negative look-behind (no need to rewrite queries that already use DISTINCT).
$query = preg_replace('/(SELECT.*)(?:'. $table .'\.|\s)(?<!DISTINCT\()(?<!DISTINCT\('. $table .'\.)'. $field .'(.*FROM )/AUsi', '\1 '. $field_to_select .'\2', $query);
$query = preg_replace('/(ORDER BY )(?!'. $table .'\.'. $field .')/', '\1'."$table.$field, ", $query);
return $query;
}
/**
* @} End of "ingroup database".
*/
/**
* @ingroup schemaapi
* @{
*/
/**
* This maps a generic data type in combination with its data size
* to the engine-specific data type.
*/
function db_type_map() {
// Put :normal last so it gets preserved by array_flip. This makes
// it much easier for modules (such as schema.module) to map
// database types back into schema types.
$map = array(
'varchar:normal' => 'varchar',
'char:normal' => 'character',
'text:tiny' => 'text',
'text:small' => 'text',
'text:medium' => 'text',
'text:big' => 'text',
'text:normal' => 'text',
'int:tiny' => 'smallint',
'int:small' => 'smallint',
'int:medium' => 'int',
'int:big' => 'bigint',
'int:normal' => 'int',
'float:tiny' => 'real',
'float:small' => 'real',
'float:medium' => 'real',
'float:big' => 'double precision',
'float:normal' => 'real',
'numeric:normal' => 'numeric',
'blob:big' => 'bytea',
'blob:normal' => 'bytea',
'datetime:normal' => 'timestamp',
'serial:tiny' => 'serial',
'serial:small' => 'serial',
'serial:medium' => 'serial',
'serial:big' => 'bigserial',
'serial:normal' => 'serial',
);
return $map;
}
/**
* Generate SQL to create a new table from a Drupal schema definition.
*
* @param $name
* The name of the table to create.
* @param $table
* A Schema API table definition array.
* @return
* An array of SQL statements to create the table.
*/
function db_create_table_sql($name, $table) {
$sql_fields = array();
foreach ($table['fields'] as $field_name => $field) {
$sql_fields[] = _db_create_field_sql($field_name, _db_process_field($field));
}
$sql_keys = array();
if (isset($table['primary key']) && is_array($table['primary key'])) {
$sql_keys[] = 'PRIMARY KEY ('. implode(', ', $table['primary key']) .')';
}
if (isset($table['unique keys']) && is_array($table['unique keys'])) {
foreach ($table['unique keys'] as $key_name => $key) {
$sql_keys[] = 'CONSTRAINT {'. $name .'}_'. $key_name .'_key UNIQUE ('. implode(', ', $key) .')';
}
}
$sql = "CREATE TABLE {". $name ."} (\n\t";
$sql .= implode(",\n\t", $sql_fields);
if (count($sql_keys) > 0) {
$sql .= ",\n\t";
}
$sql .= implode(",\n\t", $sql_keys);
$sql .= "\n)";
$statements[] = $sql;
if (isset($table['indexes']) && is_array($table['indexes'])) {
foreach ($table['indexes'] as $key_name => $key) {
$statements[] = _db_create_index_sql($name, $key_name, $key);
}
}
return $statements;
}
function _db_create_index_sql($table, $name, $fields) {
$query = 'CREATE INDEX {'. $table .'}_'. $name .'_idx ON {'. $table .'} (';
$query .= _db_create_key_sql($fields) .')';
return $query;
}
function _db_create_key_sql($fields) {
$ret = array();
foreach ($fields as $field) {
if (is_array($field)) {
$ret[] = 'substr('. $field[0] .', 1, '. $field[1] .')';
}
else {
$ret[] = $field;
}
}
return implode(', ', $ret);
}
function _db_create_keys(&$ret, $table, $new_keys) {
if (isset($new_keys['primary key'])) {
db_add_primary_key($ret, $table, $new_keys['primary key']);
}
if (isset($new_keys['unique keys'])) {
foreach ($new_keys['unique keys'] as $name => $fields) {
db_add_unique_key($ret, $table, $name, $fields);
}
}
if (isset($new_keys['indexes'])) {
foreach ($new_keys['indexes'] as $name => $fields) {
db_add_index($ret, $table, $name, $fields);
}
}
}
/**
* Set database-engine specific properties for a field.
*
* @param $field
* A field description array, as specified in the schema documentation.
*/
function _db_process_field($field) {
if (!isset($field['size'])) {
$field['size'] = 'normal';
}
// Set the correct database-engine specific datatype.
if (!isset($field['pgsql_type'])) {
$map = db_type_map();
$field['pgsql_type'] = $map[$field['type'] .':'. $field['size']];
}
if ($field['type'] == 'serial') {
unset($field['not null']);
}
return $field;
}
/**
* Create an SQL string for a field to be used in table creation or alteration.
*
* Before passing a field out of a schema definition into this function it has
* to be processed by _db_process_field().
*
* @param $name
* Name of the field.
* @param $spec
* The field specification, as per the schema data structure format.
*/
function _db_create_field_sql($name, $spec) {
$sql = $name .' '. $spec['pgsql_type'];
if ($spec['type'] == 'serial') {
unset($spec['not null']);
}
if (!empty($spec['unsigned'])) {
if ($spec['type'] == 'serial') {
$sql .= " CHECK ($name >= 0)";
}
else {
$sql .= '_unsigned';
}
}
if (!empty($spec['length'])) {
$sql .= '('. $spec['length'] .')';
}
elseif (isset($spec['precision']) && isset($spec['scale'])) {
$sql .= '('. $spec['precision'] .', '. $spec['scale'] .')';
}
if (isset($spec['not null']) && $spec['not null']) {
$sql .= ' NOT NULL';
}
if (isset($spec['default'])) {
$default = is_string($spec['default']) ? "'". $spec['default'] ."'" : $spec['default'];
$sql .= " default $default";
}
return $sql;
}
/**
* Rename a table.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be renamed.
* @param $new_name
* The new name for the table.
*/
function db_rename_table(&$ret, $table, $new_name) {
$ret[] = update_sql('ALTER TABLE {'. $table .'} RENAME TO {'. $new_name .'}');
}
/**
* Drop a table.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be dropped.
*/
function db_drop_table(&$ret, $table) {
$ret[] = update_sql('DROP TABLE {'. $table .'}');
}
/**
* Add a new field to a table.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* Name of the table to be altered.
* @param $field
* Name of the field to be added.
* @param $spec
* The field specification array, as taken from a schema definition.
* The specification may also contain the key 'initial', the newly
* created field will be set to the value of the key in all rows.
* This is most useful for creating NOT NULL columns with no default
* value in existing tables.
* @param $keys_new
* Optional keys and indexes specification to be created on the
* table along with adding the field. The format is the same as a
* table specification but without the 'fields' element. If you are
* adding a type 'serial' field, you MUST specify at least one key
* or index including it in this array. @see db_change_field for more
* explanation why.
*/
function db_add_field(&$ret, $table, $field, $spec, $new_keys = array()) {
$fixnull = FALSE;
if (!empty($spec['not null']) && !isset($spec['default'])) {
$fixnull = TRUE;
$spec['not null'] = FALSE;
}
$query = 'ALTER TABLE {'. $table .'} ADD COLUMN ';
$query .= _db_create_field_sql($field, _db_process_field($spec));
$ret[] = update_sql($query);
if (isset($spec['initial'])) {
// All this because update_sql does not support %-placeholders.
$sql = 'UPDATE {'. $table .'} SET '. $field .' = '. db_type_placeholder($spec['type']);
$result = db_query($sql, $spec['initial']);
$ret[] = array('success' => $result !== FALSE, 'query' => check_plain($sql .' ('. $spec['initial'] .')'));
}
if ($fixnull) {
$ret[] = update_sql("ALTER TABLE {". $table ."} ALTER $field SET NOT NULL");
}
if (isset($new_keys)) {
_db_create_keys($ret, $table, $new_keys);
}
}
/**
* Drop a field.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $field
* The field to be dropped.
*/
function db_drop_field(&$ret, $table, $field) {
$ret[] = update_sql('ALTER TABLE {'. $table .'} DROP COLUMN '. $field);
}
/**
* Set the default value for a field.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $field
* The field to be altered.
* @param $default
* Default value to be set. NULL for 'default NULL'.
*/
function db_field_set_default(&$ret, $table, $field, $default) {
if ($default == NULL) {
$default = 'NULL';
}
else {
$default = is_string($default) ? "'$default'" : $default;
}
$ret[] = update_sql('ALTER TABLE {'. $table .'} ALTER COLUMN '. $field .' SET DEFAULT '. $default);
}
/**
* Set a field to have no default value.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $field
* The field to be altered.
*/
function db_field_set_no_default(&$ret, $table, $field) {
$ret[] = update_sql('ALTER TABLE {'. $table .'} ALTER COLUMN '. $field .' DROP DEFAULT');
}
/**
* Add a primary key.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $fields
* Fields for the primary key.
*/
function db_add_primary_key(&$ret, $table, $fields) {
$ret[] = update_sql('ALTER TABLE {'. $table .'} ADD PRIMARY KEY ('.
implode(',', $fields) .')');
}
/**
* Drop the primary key.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
*/
function db_drop_primary_key(&$ret, $table) {
$ret[] = update_sql('ALTER TABLE {'. $table .'} DROP CONSTRAINT {'. $table .'}_pkey');
}
/**
* Add a unique key.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $name
* The name of the key.
* @param $fields
* An array of field names.
*/
function db_add_unique_key(&$ret, $table, $name, $fields) {
$name = '{'. $table .'}_'. $name .'_key';
$ret[] = update_sql('ALTER TABLE {'. $table .'} ADD CONSTRAINT '.
$name .' UNIQUE ('. implode(',', $fields) .')');
}
/**
* Drop a unique key.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $name
* The name of the key.
*/
function db_drop_unique_key(&$ret, $table, $name) {
$name = '{'. $table .'}_'. $name .'_key';
$ret[] = update_sql('ALTER TABLE {'. $table .'} DROP CONSTRAINT '. $name);
}
/**
* Add an index.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $name
* The name of the index.
* @param $fields
* An array of field names.
*/
function db_add_index(&$ret, $table, $name, $fields) {
$ret[] = update_sql(_db_create_index_sql($table, $name, $fields));
}
/**
* Drop an index.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
* @param $name
* The name of the index.
*/
function db_drop_index(&$ret, $table, $name) {
$name = '{'. $table .'}_'. $name .'_idx';
$ret[] = update_sql('DROP INDEX '. $name);
}
/**
* Change a field definition.
*
* IMPORTANT NOTE: To maintain database portability, you have to explicitly
* recreate all indices and primary keys that are using the changed field.
*
* That means that you have to drop all affected keys and indexes with
* db_drop_{primary_key,unique_key,index}() before calling db_change_field().
* To recreate the keys and indices, pass the key definitions as the
* optional $new_keys argument directly to db_change_field().
*
* For example, suppose you have:
* @code
* $schema['foo'] = array(
* 'fields' => array(
* 'bar' => array('type' => 'int', 'not null' => TRUE)
* ),
* 'primary key' => array('bar')
* );
* @endcode
* and you want to change foo.bar to be type serial, leaving it as the
* primary key. The correct sequence is:
* @code
* db_drop_primary_key($ret, 'foo');
* db_change_field($ret, 'foo', 'bar', 'bar',
* array('type' => 'serial', 'not null' => TRUE),
* array('primary key' => array('bar')));
* @endcode
*
* The reasons for this are due to the different database engines:
*
* On PostgreSQL, changing a field definition involves adding a new field
* and dropping an old one which* causes any indices, primary keys and
* sequences (from serial-type fields) that use the changed field to be dropped.
*
* On MySQL, all type 'serial' fields must be part of at least one key
* or index as soon as they are created. You cannot use
* db_add_{primary_key,unique_key,index}() for this purpose because
* the ALTER TABLE command will fail to add the column without a key
* or index specification. The solution is to use the optional
* $new_keys argument to create the key or index at the same time as
* field.
*
* You could use db_add_{primary_key,unique_key,index}() in all cases
* unless you are converting a field to be type serial. You can use
* the $new_keys argument in all cases.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* Name of the table.
* @param $field
* Name of the field to change.
* @param $field_new
* New name for the field (set to the same as $field if you don't want to change the name).
* @param $spec
* The field specification for the new field.
* @param $new_keys
* Optional keys and indexes specification to be created on the
* table along with changing the field. The format is the same as a
* table specification but without the 'fields' element.
*/
function db_change_field(&$ret, $table, $field, $field_new, $spec, $new_keys = array()) {
$ret[] = update_sql("ALTER TABLE {". $table ."} RENAME $field TO ". $field ."_old");
$not_null = isset($spec['not null']) ? $spec['not null'] : FALSE;
unset($spec['not null']);
db_add_field($ret, $table, "$field_new", $spec);
$ret[] = update_sql("UPDATE {". $table ."} SET $field_new = ". $field ."_old");
if ($not_null) {
$ret[] = update_sql("ALTER TABLE {". $table ."} ALTER $field_new SET NOT NULL");
}
db_drop_field($ret, $table, $field .'_old');
if (isset($new_keys)) {
_db_create_keys($ret, $table, $new_keys);
}
}
/**
* @} End of "ingroup schemaapi".
*/
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