--- /dev/null
+<?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\Schema;
+
+use Doctrine\DBAL\Schema\Visitor\Visitor;
+
+/**
+ * Sequence Structure
+ *
+ *
+ * @link www.doctrine-project.org
+ * @since 2.0
+ * @version $Revision$
+ * @author Benjamin Eberlei <kontakt@beberlei.de>
+ */
+class Sequence extends AbstractAsset
+{
+ /**
+ * @var int
+ */
+ protected $_allocationSize = 1;
+
+ /**
+ * @var int
+ */
+ protected $_initialValue = 1;
+
+ /**
+ *
+ * @param string $name
+ * @param int $allocationSize
+ * @param int $initialValue
+ */
+ public function __construct($name, $allocationSize=1, $initialValue=1)
+ {
+ $this->_setName($name);
+ $this->_allocationSize = (is_numeric($allocationSize))?$allocationSize:1;
+ $this->_initialValue = (is_numeric($initialValue))?$initialValue:1;
+ }
+
+ public function getAllocationSize()
+ {
+ return $this->_allocationSize;
+ }
+
+ public function getInitialValue()
+ {
+ return $this->_initialValue;
+ }
+
+ public function setAllocationSize($allocationSize)
+ {
+ $this->_allocationSize = (is_numeric($allocationSize))?$allocationSize:1;
+ }
+
+ public function setInitialValue($initialValue)
+ {
+ $this->_initialValue = (is_numeric($initialValue))?$initialValue:1;
+ }
+
+ /**
+ * Check if this sequence is an autoincrement sequence for a given table.
+ *
+ * This is used inside the comparator to not report sequences as missing,
+ * when the "from" schema implicitly creates the sequences.
+ *
+ * @param Table $table
+ *
+ * @return bool
+ */
+ public function isAutoIncrementsFor(Table $table)
+ {
+ if ( ! $table->hasPrimaryKey()) {
+ return false;
+ }
+
+ $pkColumns = $table->getPrimaryKey()->getColumns();
+
+ if (count($pkColumns) != 1) {
+ return false;
+ }
+
+ $column = $table->getColumn($pkColumns[0]);
+
+ if ( ! $column->getAutoincrement()) {
+ return false;
+ }
+
+ $sequenceName = $this->getShortestName($table->getNamespaceName());
+ $tableName = $table->getShortestName($table->getNamespaceName());
+ $tableSequenceName = sprintf('%s_%s_seq', $tableName, $pkColumns[0]);
+
+ return $tableSequenceName === $sequenceName;
+ }
+
+ /**
+ * @param Visitor $visitor
+ */
+ public function visit(Visitor $visitor)
+ {
+ $visitor->acceptSequence($this);
+ }
+}