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Diffstat (limited to 'includes/database/pgsql/schema.inc')
| -rw-r--r-- | includes/database/pgsql/schema.inc | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/includes/database/pgsql/schema.inc b/includes/database/pgsql/schema.inc new file mode 100644 index 000000000..fa817c4d1 --- /dev/null +++ b/includes/database/pgsql/schema.inc @@ -0,0 +1,509 @@ +<?php +// $Id$ + +/** + * @file + * Database schema code for PostgreSQL database servers. + */ + +/** + * @ingroup schemaapi + * @{ + */ + +class DatabaseSchema_pgsql extends DatabaseSchema { + + public function tableExists($table) { + return (bool) db_result(db_query("SELECT COUNT(*) FROM pg_class WHERE relname = '{" . db_escape_table($table) . "}'")); + } + + public function columnExists($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) . "'")); + } + + /** + * Generate SQL to create a new table from a Drupal schema definition. + * + * @param $name + * The name of the table to create. + * @param $table + * A Schema API table definition array. + * @return + * An array of SQL statements to create the table. + */ + protected function createTableSql($name, $table) { + $sql_fields = array(); + foreach ($table['fields'] as $field_name => $field) { + $sql_fields[] = $this->createFieldSql($field_name, $this->processField($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[] = $this->_createIndexSql($name, $key_name, $key); + } + } + + return $statements; + } + + /** + * 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 $spec + * The field specification, as per the schema data structure format. + */ + protected function createFieldSql($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; + } + + /** + * Set database-engine specific properties for a field. + * + * @param $field + * A field description array, as specified in the schema documentation. + */ + protected function processField($field) { + if (!isset($field['size'])) { + $field['size'] = 'normal'; + } + // Set the correct database-engine specific datatype. + if (!isset($field['pgsql_type'])) { + $map = $this->getFieldTypeMap(); + $field['pgsql_type'] = $map[$field['type'] . ':' . $field['size']]; + } + if ($field['type'] == 'serial') { + unset($field['not null']); + } + return $field; + } + + + /** + * This maps a generic data type in combination with its data size + * to the engine-specific data type. + */ + function getFieldTypeMap() { + // 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 $map; + } + + protected function _createKeySql($fields) { + $ret = array(); + foreach ($fields as $field) { + if (is_array($field)) { + $ret[] = 'substr(' . $field[0] . ', 1, ' . $field[1] . ')'; + } + else { + $ret[] = $field; + } + } + return implode(', ', $ret); + } + + /** + * Rename a table. + * + * @param $ret + * Array to which query results will be added. + * @param $table + * The table to be renamed. + * @param $new_name + * The new name for the table. + */ + function renameTable(&$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 $table + * The table to be dropped. + */ + public function dropTable(&$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 $keys_new + * Optional keys and indexes specification to be created on the + * table along with adding the field. The format is the same as a + * table specification but without the 'fields' element. If you are + * adding a type 'serial' field, you MUST specify at least one key + * or index including it in this array. @see db_change_field for more + * explanation why. + */ + public function addField(&$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 .= $this->_createFieldSql($field, $this->_processField($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)) { + $this->_createKeys($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 $field + * The field to be dropped. + */ + public function dropField(&$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 $default + * Default value to be set. NULL for 'default NULL'. + */ + public function fieldSetDefault(&$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 $field + * The field to be altered. + */ + public function fieldSetNoDefault(&$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 $fields + * Fields for the primary key. + */ + public function addPrimaryKey(&$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 $table + * The table to be altered. + */ + public function dropPrimaryKey(&$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 $fields + * An array of field names. + */ + function addUniqueKey(&$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 $name + * The name of the key. + */ + public function dropUniqueKey(&$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 $fields + * An array of field names. + */ + public function addIndex(&$ret, $table, $name, $fields) { + $ret[] = update_sql($this->_createIndexSql($table, $name, $fields)); + } + + /** + * Drop an index. + * + * @param $ret + * Array to which query results will be added. + * @param $table + * The table to be altered. + * @param $name + * The name of the index. + */ + public function dropIndex(&$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 $new_keys + * Optional keys and indexes specification to be created on the + * table along with changing the field. The format is the same as a + * table specification but without the 'fields' element. + */ + public function changeField(&$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']); + + $this->addField($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"); + } + + $this->dropField($ret, $table, $field . '_old'); + + if (isset($new_keys)) { + $this->_createKeys($ret, $table, $new_keys); + } + } + + protected function _createIndexSql($table, $name, $fields) { + $query = 'CREATE INDEX {' . $table . '}_' . $name . '_idx ON {' . $table . '} ('; + $query .= $this->_createKeySql($fields) . ')'; + return $query; + } + + protected function _createKeys(&$ret, $table, $new_keys) { + if (isset($new_keys['primary key'])) { + $this->addPrimaryKey($ret, $table, $new_keys['primary key']); + } + if (isset($new_keys['unique keys'])) { + foreach ($new_keys['unique keys'] as $name => $fields) { + $this->addUniqueKey($ret, $table, $name, $fields); + } + } + if (isset($new_keys['indexes'])) { + foreach ($new_keys['indexes'] as $name => $fields) { + $this->addIndex($ret, $table, $name, $fields); + } + } + } +} |