drupal/includes/database/sqlite/schema.inc

584 lines
17 KiB
PHP

<?php
// $Id$
/**
* @file
* Database schema code for SQLite databases.
*/
/**
* @ingroup schemaapi
* @{
*/
class DatabaseSchema_sqlite extends DatabaseSchema {
public function tableExists($table) {
// Don't use {} around sqlite_master table.
return (bool) $this->connection->query("SELECT name FROM sqlite_master WHERE type = 'table' AND name LIKE '{" . $table . "}'", array(), array())->fetchField();
}
public function columnExists($table, $column) {
$schema = $this->introspectSchema($table);
return !empty($schema['fields'][$column]);
}
/**
* Generate SQL to create a new table from a Drupal schema definition.
*
* @param $name
* The name of the table to create.
* @param $table
* A Schema API table definition array.
* @return
* An array of SQL statements to create the table.
*/
public function createTableSql($name, $table) {
$sql = array();
$sql[] = "CREATE TABLE {" . $name . "} (\n" . $this->createColumsSql($name, $table) . "\n);\n";
return array_merge($sql, $this->createIndexSql($name, $table));
}
/**
* Build the SQL expression for indexes.
*/
protected function createIndexSql($tablename, $schema) {
$sql = array();
if (!empty($schema['unique keys'])) {
foreach ($schema['unique keys'] as $key => $fields) {
$sql[] = 'CREATE UNIQUE INDEX "{' . $tablename . '}_' . $key . '" ON {' . $tablename . '} (' . $this->createKeySql($fields) . "); \n";
}
}
if (!empty($schema['indexes'])) {
foreach ($schema['indexes'] as $index => $fields) {
$sql[] = 'CREATE INDEX "{' . $tablename . '}_' . $index . '" ON {' . $tablename . '} (' . $this->createKeySql($fields) . "); \n";
}
}
return $sql;
}
/**
* Build the SQL expression for creating columns.
*/
protected function createColumsSql($tablename, $schema) {
$sql_array = array();
// Add the SQL statement for each field.
foreach ($schema['fields'] as $name => $field) {
if ($field['type'] == 'serial') {
if (isset($schema['primary key']) && ($key = array_search($name, $schema['primary key'])) !== FALSE) {
unset($schema['primary key'][$key]);
}
}
$sql_array[] = $this->createFieldSql($name, $this->processField($field));
}
// Process keys.
if (!empty($schema['primary key'])) {
$sql_array[] = " PRIMARY KEY (" . $this->createKeySql($schema['primary key']) . ")";
}
return implode(", \n", $sql_array);
}
/**
* Build the SQL expression for keys.
*/
protected function createKeySql($fields) {
$ret = array();
foreach ($fields as $field) {
if (is_array($field)) {
$ret[] = $field[0];
}
else {
$ret[] = $field;
}
}
return implode(', ', $ret);
}
/**
* 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['sqlite_type'])) {
$map = $this->getFieldTypeMap();
$field['sqlite_type'] = $map[$field['type'] . ':' . $field['size']];
}
if ($field['type'] == 'serial') {
$field['auto_increment'] = TRUE;
}
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_processField().
*
* @param $name
* Name of the field.
* @param $spec
* The field specification, as per the schema data structure format.
*/
protected function createFieldSql($name, $spec) {
if (!empty($spec['auto_increment'])) {
$sql = $name . " INTEGER PRIMARY KEY AUTOINCREMENT";
}
else {
$sql = $name . " " . $spec['sqlite_type'];
if (in_array($spec['type'], array('varchar', 'char', 'text')) && isset($spec['length'])) {
$sql .= '(' . $spec['length'] . ')';
}
if (!empty($spec['not null'])) {
$sql .= ' NOT NULL';
}
if (isset($spec['default'])) {
if (is_string($spec['default'])) {
$spec['default'] = "'" . $spec['default'] . "'";
}
$sql .= ' DEFAULT ' . $spec['default'];
}
if (empty($spec['not null']) && !isset($spec['default'])) {
$sql .= ' DEFAULT NULL';
}
}
return $sql;
}
/**
* This maps a generic data type in combination with its data size
* to the engine-specific data type.
*/
public 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 does not use drupal_static as its value never changes.
static $map = array(
'varchar:normal' => 'VARCHAR',
'text:tiny' => 'TEXT',
'text:small' => 'TEXT',
'text:medium' => 'TEXT',
'text:big' => 'TEXT',
'text:normal' => 'TEXT',
'serial:tiny' => 'INTEGER',
'serial:small' => 'INTEGER',
'serial:medium' => 'INTEGER',
'serial:big' => 'INTEGER',
'serial:normal' => 'INTEGER',
'int:tiny' => 'INTEGER',
'int:small' => 'INTEGER',
'int:medium' => 'INTEGER',
'int:big' => 'INTEGER',
'int:normal' => 'INTEGER',
'float:tiny' => 'FLOAT',
'float:small' => 'FLOAT',
'float:medium' => 'FLOAT',
'float:big' => 'FLOAT',
'float:normal' => 'FLOAT',
'numeric:normal' => 'NUMERIC',
'blob:big' => 'BLOB',
'blob:normal' => 'BLOB',
'date:normal' => 'DATE',
'time:normal' => 'TIME',
'datetime:normal' => 'TIMESTAMP',
);
return $map;
}
/**
* Rename a table.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be renamed.
* @param $new_name
* The new name for the table.
*/
public function renameTable(&$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 $spec
* The field specification array, as taken from a schema definition.
*/
public function addField(&$ret, $table, $field, $spec, $keys_new = array()) {
// TODO: $keys_new is not supported yet.
$query = 'ALTER TABLE {' . $table . '} ADD ';
$query .= $this->createFieldSql($field, $this->processField($spec));
$ret[] = update_sql($query);
}
/**
* Create a table with a new schema containing the old content.
*
* As SQLite does not support ALTER TABLE (with a few exceptions) it is
* necessary to create a new table and copy over the old content.
*
* @param $ret
* Array to which query results will be added.
* @param $table
* Name of the table to be altered.
* @param $new_schema
* The new schema array for the table.
*/
protected function alterTable(&$ret, $table, $new_schema) {
$i = 0;
do {
$new_table = $table . '_' . $i++;
} while ($this->tableExists($new_table));
$this->createTable($ret, $new_table, $new_schema);
$fields = implode(', ', array_keys($new_schema['fields']));
$ret[] = update_sql('INSERT INTO {' . $new_table . "} ($fields) SELECT $fields FROM {" . $table . '}');
$old_count = db_query('SELECT COUNT(*) FROM {' . $table . '}')->fetchField();
$new_count = db_query('SELECT COUNT(*) FROM {' . $new_table . '}')->fetchField();
if ($old_count == $new_count) {
do {
$temp_table = $table . '_' . $i++;
} while ($this->tableExists($temp_table));
$this->renameTable($ret, $table, $temp_table);
$this->renameTable($ret, $new_table, $table);
$this->dropTable($ret, $temp_table);
}
}
/**
* Find out the schema of a table.
*
* This function uses introspection methods provided by the database to
* create a schema array. This is useful, for example, during update when
* the old schema is not available.
*
* @param $table
* Name of the table.
* @return
* An array representing the schema, from drupal_get_schema().
* @see drupal_get_schema()
*/
protected function introspectSchema($table) {
$mapped_fields = array_flip($this->getFieldTypeMap());
$schema = array();
foreach (db_query("PRAGMA table_info('{" . $table . "}')") as $row) {
if (preg_match('/^([^(]+)\((.*)\)$/', $row->type, $matches)) {
$type = $matches[1];
$length = $matches[2];
}
else {
$type = $row->type;
$length = NULL;
}
if (isset($mapped_fields[$type])) {
list($type, $size) = explode(':', $mapped_fields[$type]);
$schema['fields'][$row->name] = array(
'type' => $type,
'size' => $size,
'not null' => !empty($row->notnull),
'default' => trim($row->dflt_value, "'"),
);
if ($length) {
$schema['fields'][$row->name]['length'] = $length;
}
if ($row->pk) {
$schema['primary key'][] = $row->name;
}
}
else {
new Exception("Unable to parse the column type " . $row->type);
}
}
$indexes = array();
foreach (db_query("PRAGMA index_list('{" . $table . "}')") as $row) {
if (strpos($row->name, 'sqlite_autoindex_') !== 0) {
$indexes[] = array(
'schema_key' => $row->unique ? 'unique keys' : 'indexes',
'name' => $row->name,
);
}
}
$n = strlen($table) + 1;
foreach ($indexes as $index) {
$name = $index['name'];
$index_name = substr($name, $n);
foreach (db_query("PRAGMA index_info('$name')") as $row) {
$schema[$index['schema_key']][$index_name][] = $row->name;
}
}
return $schema;
}
/**
* Drop a field.
*
* This implementation can't use ALTER TABLE directly, because SQLite only
* supports a limited subset of that command.
*
* @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) {
$new_schema = $this->introspectSchema($table);
unset($new_schema['fields'][$field]);
foreach ($new_schema['indexes'] as $index => $fields) {
foreach ($fields as $key => $field_name) {
if ($field_name == $field) {
unset($new_schema['indexes'][$index][$key]);
}
}
// If this index has no more fields then remove it.
if (empty($new_schema['indexes'][$index])) {
unset($new_schema['indexes'][$index]);
}
}
$this->alterTable($ret, $table, $new_schema);
}
/**
* Change a field definition.
*
* This implementation can't use ALTER TABLE directly, because SQLite only
* supports a limited subset of that command.
*
* @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 $keys_new
* Optional keys and indexes specification to be created on the
* table along with changing the field. The format is the same as a
* table specification but without the 'fields' element.
*/
public function changeField(&$ret, $table, $field, $field_new, $spec, $keys_new = array()) {
$new_schema = $this->introspectSchema($table);
unset($new_schema['fields'][$field]);
$new_schema['fields'][$field_new] = $spec;
if (isset($keys_new['primary keys'])) {
$new_schema['primary keys'] = $keys_new['primary keys'];
$keys_new['primary keys'];
}
foreach (array('unique keys', 'indexes') as $k) {
if (!empty($keys_new[$k])) {
$new_schema[$k] = $keys_new[$k] + $new_schema[$k];
}
}
$this->alterTable($ret, $table, $new_schema);
}
/**
* 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) {
$schema['indexes'][$name] = $fields;
$statements = $this->createIndexSql($table, $schema);
foreach ($statements as $statement) {
$ret[] = update_sql($statement);
}
}
/**
* 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) {
$ret[] = update_sql('DROP INDEX ' . '{' . $table . '}_' . $name);
}
/**
* 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 $fields
* An array of field names.
*/
public function addUniqueKey(&$ret, $table, $name, $fields) {
$schema['unique keys'][$name] = $fields;
$statements = $this->createIndexSql($table, $schema);
foreach ($statements as $statement) {
$ret[] = update_sql($statement);
}
}
/**
* 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) {
$ret[] = update_sql('DROP INDEX ' . '{' . $table . '}_' . $name);
}
/**
* Add a primary key.
*
* This implementation can't use ALTER TABLE directly, because SQLite only
* supports a limited subset of that command.
*
* @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) {
$new_schema = $this->introspectSchema($table);
$new_schema['primary key'] = $fields;
$this->alterTable($ret, $table, $new_schema);
}
/**
* Drop the primary key.
*
* This implementation can't use ALTER TABLE directly, because SQLite only
* supports a limited subset of that command.`
*
* @param $ret
* Array to which query results will be added.
* @param $table
* The table to be altered.
*/
public function dropPrimaryKey(&$ret, $table) {
$new_schema = $this->introspectSchema($table);
unset($new_schema['primary key']);
$this->alterTable($ret, $table, $new_schema);
}
/**
* Set the default value for a field.
*
* This implementation can't use ALTER TABLE directly, because SQLite only
* supports a limited subset of that command.
*
* @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) {
$new_schema = $this->introspectSchema($table);
$new_schema['fields'][$field]['default'] = $default;
$this->alterTable($ret, $table, $new_schema);
}
/**
* Set a field to have no default value.
*
* This implementation can't use ALTER TABLE directly, because SQLite only
* supports a limited subset of that command.
*
* @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) {
$new_schema = $this->introspectSchema($table);
unset($new_schema['fields'][$field]['default']);
$this->alterTable($ret, $table, $new_schema);
}
/**
* Find all tables that are like the specified base table name.
*
* @param $table_expression
* An SQL expression, for example "simpletest%" (without the quotes).
* BEWARE: this is not prefixed, the caller should take care of that.
* @return
* Array, both the keys and the values are the matching tables.
*/
public function findTables($table_expression) {
// Don't use {} around sqlite_master table.
$result = db_query("SELECT name FROM sqlite_master WHERE name LIKE :table_name", array(
':table_name' => $table_expression,
));
return $result->fetchAllKeyed(0, 0);
}
}