Table.php

<?php
class ZendDbSchema_Db_Schema_Generator_Mysql_Table
    implements ZendDbSchema_Db_Schema_Generator_Table
{
    public function createTable(ZendDbSchema_Db_Schema_Table $schema)
    {
        $name = $schema->getName();

        $engine = $schema->engine;
        if ($engine) {
            $engine = "ENGINE={$engine}";
        }

        $charset = $schema->charset;
        if ($charset) {
            $charset = "DEFAULT CHARSET={$charset}";
        }

        $query = array();
        foreach ($schema->columns() as $column) {
            $query[] = $column->toSql();
        }

        $query = array_filter($query);
        $query = join(', ' . PHP_EOL, $query);

        $query = "DROP TABLE IF EXISTS `{$name}`;" . PHP_EOL
               . "CREATE TABLE `{$name}` (" . PHP_EOL
               . $query . PHP_EOL
               . ") {$engine} {$charset}";

        return $query;
    }

    public function alterTable(ZendDbSchema_Db_Schema_Table $schema)
    {
        if (!$schema->isExist()) {
            return null;
        }

        $props = array();
        if ($schema->isDirty('engine')) {
            $props[] = "ENGINE={$schema->engine}";
        }

        if ($schema->isDirty('charset')) {
            $props[] = "DEFAULT CHARSET={$schema->charset}";
        }

        $props = array_filter($props);
        $props = join(', ' . PHP_EOL, $props);

        $query = array();

        $name = $schema->getName();
        if ($schema->isDirty(ZendDbSchema_Db_Schema_Table::NAME_KEY)) {
            $oldName = $schema->getOriginName();
            if ($oldName && $oldName != $name) {
                $query[] = "RENAME TABLE `{$oldName}` TO `{$name}`";
            }
        }
        if ($props) {
            $query[] = "ALTER TABLE `{$name}` {$props}";
        }

        return join(';' . PHP_EOL, $query);
    }

    public function dropTable(ZendDbSchema_Db_Schema_Table $schema)
    {
        if (!$schema->isExist()) {
            return null;
        }
        return "DROP TABLE IF EXISTS {$schema->getOriginName()}";
    }

    protected function _columnSql(ZendDbSchema_Db_Schema_Table_Column $schema)
    {
        $query = array();

        $query[] = $schema->type . "({$schema->length})";

        if (!$schema->isNullable()) {
            $query[] = "NOT NULL";
        } elseif (null === $schema->default) {

            $query[] = "DEFAULT NULL";
        }

        if (null !== $schema->default) {
            $query[] = "DEFAULT {$schema->default}";
        }

        $query[] = "COMMENT '{$schema->comment}'";

        if (false === $schema->isSigned()) {
            $query[] = "UNSIGNED";
        } elseif (true === $schema->isSigned()) {
            $query[] = "SIGNED";
        }

        if ($schema->autoincrement) {
            $query[] = "AUTO_INCREMENT";
        }

        if ($schema->after) {
            $query[] = "AFTER {$schema->after}";
        }

        return join(' ', $query);
    }

    public function createColumn(ZendDbSchema_Db_Schema_Table_Column $schema)
    {
        $name = $schema->getName();
        return "`{$name}`" . ' ' . $this->_columnSql($schema);
    }

    public function alterColumn(ZendDbSchema_Db_Schema_Table_Column $schema)
    {
        if (!$schema->getTable()->isExist() || !$schema->isDirty()) {
            return null;
        }
        $name   = $schema->getName();

        $query = array();
        $query[] = "ALTER TABLE `{$schema->getTable()->getName()}`";

        if ($schema->isExist()) {
            $oldName = $schema->getOriginName();
            if ($oldName && $oldName != $name) {
                $oldName = $schema->getOriginName();
                $query[] = "CHANGE `{$name}` `{$oldName}`";
            } else {
                $query[] = "MODIFY `{$name}`";
            }
        } else {
            $query[] = "ADD `{$name}`";
        }

        return join(' ', $query) . ' ' . $this->_columnSql($schema);
    }

    public function dropColumn(ZendDbSchema_Db_Schema_Table_Column $schema)
    {
        $name   = $schema->getName();
        $table =  $schema->getTable()->getName();

        return "ALTER TABLE {$table} DROP COLUMN {$name}";
    }

    public function createIndex(ZendDbSchema_Db_Schema_Table_Index $schema)
    {
        $name   = $schema->getName();
        $table =  $schema->getTable()->getName();

        $columns = "";
        if ($schema->getColumns()) {
            $columns = "(" . join(', ', $schema->getColumns()) . ")";
        }
        $type = strtoupper($schema->type);

        $query = array();
        if ($schema->isExist()) {
            $query[] = $this->dropIndex($schema);
        }
        $query[] = "CREATE {$type} INDEX `{$name}` ON `{$table}` {$columns}";

        return join(';' . PHP_EOL, $query);
    }

    public function alterIndex(ZendDbSchema_Db_Schema_Table_Index $schema)
    {
        return $this->createIndex($schema);
    }

    public function dropIndex(ZendDbSchema_Db_Schema_Table_Index $schema)
    {
        $name   = $schema->getName();
        $table =  $schema->getTable()->getName();

        $query = "DROP INDEX IF EXISTS `{$name}` ON `{$table}`";
        return $query;
    }

    public function addPrimaryKey(ZendDbSchema_Db_Schema_Table_PrimaryKey $schema)
    {
        $columns = join(', ', $schema->getColumns());
        $table = $schema->getTable()->getName();

        $query = "ALTER TABLE `{$table}` ADD PRIMARY KEY ({$columns})";

        return $query;
    }

    public function alterPrimaryKey(ZendDbSchema_Db_Schema_Table_PrimaryKey $schema)
    {
        $query = array();
        $query[] = $this->dropPrimaryKey($schema);
        $query[] = $this->addPrimaryKey($schema);

        return join(';' . PHP_EOL, $query);
    }

    public function dropPrimaryKey(ZendDbSchema_Db_Schema_Table_PrimaryKey $schema)
    {
        $table =  $schema->getTable()->getName();

        $query = "ALTER TABLE `{$table}` DROP PRIMARY KEY";
        return $query;
    }

    public function addForeignKey(ZendDbSchema_Db_Schema_Table_ForeignKey $schema)
    {
        $query = array();

        if ($name = $schema->getOriginName()) {
            $query[] = "CONSTRAINT {$name}";
        }

        $columns = $schema->getColumns();

        $refColumns = join('`,`', array_values($columns));
        $columns = join('`,`', array_keys($columns));
        $refTable = $schema->getReferences();

        $query[] = " FOREIGN KEY (`{$columns}`) REFERENCES `{$refTable}` (`{$refColumns}`)";

        if ($delete = $schema->getOnDelete()) {
            $query[] = " ON DELETE {$delete}";
        }
        if ($update = $schema->getOnUpdate()) {
            $query[] = " ON UPDATE {$update}";
        }

        $table =  $schema->getTable()->getName();

        return "ALTER TABLE `{$table}` ADD " . join(' ', $query);
    }

    public function alterForeignKey(ZendDbSchema_Db_Schema_Table_ForeignKey $schema)
    {
        $query = array();
        if ($schema->isExist()) {
            $query[] = $this->dropForeignKey($schema);
        }
        $query[] = $this->addForeignKey($schema);
        return join(';' . PHP_EOL, $query);
    }

    public function dropForeignKey(ZendDbSchema_Db_Schema_Table_ForeignKey $schema)
    {
        $table =  $schema->getTable()->getName();
        $name = $schema->getOriginName();

        $query = "ALTER TABLE `{$table}` DROP FOREIGN KEY {$name}";
        return $query;
    }
}