<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.0.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Database\Schema;
use Cake\Database\Driver;
/**
* Base class for schema implementations.
*
* This class contains methods that are common across
* the various SQL dialects.
*/
abstract class BaseSchema
{
/**
* The driver instance being used.
*
* @var \Cake\Database\Driver
*/
protected $_driver;
/**
* Constructor
*
* This constructor will connect the driver so that methods like columnSql() and others
* will fail when the driver has not been connected.
*
* @param \Cake\Database\Driver $driver The driver to use.
*/
public function __construct(Driver $driver)
{
$driver->connect();
$this->_driver = $driver;
}
/**
* Generate an ON clause for a foreign key.
*
* @param string|null $on The on clause
* @return string
*/
protected function _foreignOnClause($on)
{
if ($on === TableSchema::ACTION_SET_NULL) {
return 'SET NULL';
}
if ($on === TableSchema::ACTION_SET_DEFAULT) {
return 'SET DEFAULT';
}
if ($on === TableSchema::ACTION_CASCADE) {
return 'CASCADE';
}
if ($on === TableSchema::ACTION_RESTRICT) {
return 'RESTRICT';
}
if ($on === TableSchema::ACTION_NO_ACTION) {
return 'NO ACTION';
}
}
/**
* Convert string on clauses to the abstract ones.
*
* @param string $clause The on clause to convert.
* @return string|null
*/
protected function _convertOnClause($clause)
{
if ($clause === 'CASCADE' || $clause === 'RESTRICT') {
return strtolower($clause);
}
if ($clause === 'NO ACTION') {
return TableSchema::ACTION_NO_ACTION;
}
return TableSchema::ACTION_SET_NULL;
}
/**
* Convert foreign key constraints references to a valid
* stringified list
*
* @param string|array $references The referenced columns of a foreign key constraint statement
* @return string
*/
protected function _convertConstraintColumns($references)
{
if (is_string($references)) {
return $this->_driver->quoteIdentifier($references);
}
return implode(', ', array_map(
[$this->_driver, 'quoteIdentifier'],
$references
));
}
/**
* Generate the SQL to drop a table.
*
* @param \Cake\Database\Schema\TableSchema $schema Schema instance
* @return array SQL statements to drop a table.
*/
public function dropTableSql(TableSchema $schema)
{
$sql = sprintf(
'DROP TABLE %s',
$this->_driver->quoteIdentifier($schema->name())
);
return [$sql];
}
/**
* Generate the SQL to list the tables.
*
* @param array $config The connection configuration to use for
* getting tables from.
* @return array An array of (sql, params) to execute.
*/
abstract public function listTablesSql($config);
/**
* Generate the SQL to describe a table.
*
* @param string $tableName The table name to get information on.
* @param array $config The connection configuration.
* @return array An array of (sql, params) to execute.
*/
abstract public function describeColumnSql($tableName, $config);
/**
* Generate the SQL to describe the indexes in a table.
*
* @param string $tableName The table name to get information on.
* @param array $config The connection configuration.
* @return array An array of (sql, params) to execute.
*/
abstract public function describeIndexSql($tableName, $config);
/**
* Generate the SQL to describe the foreign keys in a table.
*
* @param string $tableName The table name to get information on.
* @param array $config The connection configuration.
* @return array An array of (sql, params) to execute.
*/
abstract public function describeForeignKeySql($tableName, $config);
/**
* Generate the SQL to describe table options
*
* @param string $tableName Table name.
* @param array $config The connection configuration.
* @return array SQL statements to get options for a table.
*/
public function describeOptionsSql($tableName, $config)
{
return ['', ''];
}
/**
* Convert field description results into abstract schema fields.
*
* @param \Cake\Database\Schema\TableSchema $schema The table object to append fields to.
* @param array $row The row data from `describeColumnSql`.
* @return void
*/
abstract public function convertColumnDescription(TableSchema $schema, $row);
/**
* Convert an index description results into abstract schema indexes or constraints.
*
* @param \Cake\Database\Schema\TableSchema $schema The table object to append
* an index or constraint to.
* @param array $row The row data from `describeIndexSql`.
* @return void
*/
abstract public function convertIndexDescription(TableSchema $schema, $row);
/**
* Convert a foreign key description into constraints on the Table object.
*
* @param \Cake\Database\Schema\TableSchema $schema The table object to append
* a constraint to.
* @param array $row The row data from `describeForeignKeySql`.
* @return void
*/
abstract public function convertForeignKeyDescription(TableSchema $schema, $row);
/**
* Convert options data into table options.
*
* @param \Cake\Database\Schema\TableSchema $schema Table instance.
* @param array $row The row of data.
* @return void
*/
public function convertOptionsDescription(TableSchema $schema, $row)
{
}
/**
* Generate the SQL to create a table.
*
* @param \Cake\Database\Schema\TableSchema $schema Table instance.
* @param array $columns The columns to go inside the table.
* @param array $constraints The constraints for the table.
* @param array $indexes The indexes for the table.
* @return array SQL statements to create a table.
*/
abstract public function createTableSql(TableSchema $schema, $columns, $constraints, $indexes);
/**
* Generate the SQL fragment for a single column in a table.
*
* @param \Cake\Database\Schema\TableSchema $schema The table instance the column is in.
* @param string $name The name of the column.
* @return string SQL fragment.
*/
abstract public function columnSql(TableSchema $schema, $name);
/**
* Generate the SQL queries needed to add foreign key constraints to the table
*
* @param \Cake\Database\Schema\TableSchema $schema The table instance the foreign key constraints are.
* @return array SQL fragment.
*/
abstract public function addConstraintSql(TableSchema $schema);
/**
* Generate the SQL queries needed to drop foreign key constraints from the table
*
* @param \Cake\Database\Schema\TableSchema $schema The table instance the foreign key constraints are.
* @return array SQL fragment.
*/
abstract public function dropConstraintSql(TableSchema $schema);
/**
* Generate the SQL fragments for defining table constraints.
*
* @param \Cake\Database\Schema\TableSchema $schema The table instance the column is in.
* @param string $name The name of the column.
* @return string SQL fragment.
*/
abstract public function constraintSql(TableSchema $schema, $name);
/**
* Generate the SQL fragment for a single index in a table.
*
* @param \Cake\Database\Schema\TableSchema $schema The table object the column is in.
* @param string $name The name of the column.
* @return string SQL fragment.
*/
abstract public function indexSql(TableSchema $schema, $name);
/**
* Generate the SQL to truncate a table.
*
* @param \Cake\Database\Schema\TableSchema $schema Table instance.
* @return array SQL statements to truncate a table.
*/
abstract public function truncateTableSql(TableSchema $schema);
}