2018-11-05 09:26:30 +08:00

94 lines
3.2 KiB
PHP

<?php
/*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* This software consists of voluntary contributions made by many individuals
* and is licensed under the MIT license. For more information, see
* <http://www.doctrine-project.org>.
*/
namespace Doctrine\DBAL\Sharding;
/**
* Sharding Manager gives access to APIs to implementing sharding on top of
* Doctrine\DBAL\Connection instances.
*
* For simplicity and developer ease-of-use (and understanding) the sharding
* API only covers single shard queries, no fan-out support. It is primarily
* suited for multi-tenant applications.
*
* The assumption about sharding here
* is that a distribution value can be found that gives access to all the
* necessary data for all use-cases. Switching between shards should be done with
* caution, especially if lazy loading is implemented. Any query is always
* executed against the last shard that was selected. If a query is created for
* a shard Y but then a shard X is selected when its actually executed you
* will hit the wrong shard.
*
* @author Benjamin Eberlei <kontakt@beberlei.de>
*/
interface ShardManager
{
/**
* Selects global database with global data.
*
* This is the default database that is connected when no shard is
* selected.
*
* @return void
*/
function selectGlobal();
/**
* Selects the shard against which the queries after this statement will be issued.
*
* @param string $distributionValue
*
* @return void
*
* @throws \Doctrine\DBAL\Sharding\ShardingException If no value is passed as shard identifier.
*/
function selectShard($distributionValue);
/**
* Gets the distribution value currently used for sharding.
*
* @return string|null
*/
function getCurrentDistributionValue();
/**
* Gets information about the amount of shards and other details.
*
* Format is implementation specific, each shard is one element and has an
* 'id' attribute at least.
*
* @return array
*/
function getShards();
/**
* Queries all shards in undefined order and return the results appended to
* each other. Restore the previous distribution value after execution.
*
* Using {@link \Doctrine\DBAL\Connection::fetchAll} to retrieve rows internally.
*
* @param string $sql
* @param array $params
* @param array $types
*
* @return array
*/
function queryAll($sql, array $params, array $types);
}