Question

我在重建Web应用程序时正在使用旧数据库。我想使用Symfony2.x，它显然将Doctrine作为ORM。

我有大约50个（mysql）表没有主键。当我尝试生成模型时，它不允许我这样做，并在“表上没有主键”的情况下抛出异常。

我必须在表格上使用主键才能使用Doctrine，还是有任何解决方法？

任何帮助都会很棒。

感谢。

Answer 1

要求Doctrine 拥有标识符/主键。请查看此页面：http://www.doctrine-project.org/docs/orm/2.0/en/reference/basic-mapping.html#identifiers-primary-keys

但是一种从没有主键的表中生成映射和实体的方法。没有主键的表是一种不寻常和糟糕的数据库设计，但在遗留数据库的情况下存在这种情况。

<强>解决方案：
注意：以下所有引用均参考Doctrine 2.0
1.找到文件 DatabaseDriver.php （在Doctrine / ORM / Mapping / Driver / DatabaseDriver.php中）
2.找到方法 reverseEngineerMappingFromDatabase 。修改如下所述的代码。
原始代码是：

private function reverseEngineerMappingFromDatabase()
    {
        if ($this->tables !== null) {
            return;
        }

        $tables = array();

        foreach ($this->_sm->listTableNames() as $tableName) {
            $tables[$tableName] = $this->_sm->listTableDetails($tableName);
        }

        $this->tables = $this->manyToManyTables = $this->classToTableNames = array();
        foreach ($tables as $tableName => $table) {
            /* @var $table \Doctrine\DBAL\Schema\Table */
            if ($this->_sm->getDatabasePlatform()->supportsForeignKeyConstraints()) {
                $foreignKeys = $table->getForeignKeys();
            } else {
                $foreignKeys = array();
            }

            $allForeignKeyColumns = array();
            foreach ($foreignKeys as $foreignKey) {
                $allForeignKeyColumns = array_merge($allForeignKeyColumns, $foreignKey->getLocalColumns());
            }

            if ( ! $table->hasPrimaryKey()) {
                throw new MappingException(
                    "Table " . $table->getName() . " has no primary key. Doctrine does not ".
                    "support reverse engineering from tables that don't have a primary key."
                );
            }

            $pkColumns = $table->getPrimaryKey()->getColumns();
            sort($pkColumns);
            sort($allForeignKeyColumns);

            if ($pkColumns == $allForeignKeyColumns && count($foreignKeys) == 2) {
                $this->manyToManyTables[$tableName] = $table;
            } else {
                // lower-casing is necessary because of Oracle Uppercase Tablenames,
                // assumption is lower-case + underscore separated.
                $className = $this->getClassNameForTable($tableName);
                $this->tables[$tableName] = $table;
                $this->classToTableNames[$className] = $tableName;
            }
        }
    }

修改后的代码是：

private function reverseEngineerMappingFromDatabase()
    {
        if ($this->tables !== null) {
            return;
        }

        $tables = array();

        foreach ($this->_sm->listTableNames() as $tableName) {
            $tables[$tableName] = $this->_sm->listTableDetails($tableName);
        }

        $this->tables = $this->manyToManyTables = $this->classToTableNames = array();
        foreach ($tables as $tableName => $table) {
            /* @var $table \Doctrine\DBAL\Schema\Table */
            if ($this->_sm->getDatabasePlatform()->supportsForeignKeyConstraints()) {
                $foreignKeys = $table->getForeignKeys();
            } else {
                $foreignKeys = array();
            }

            $allForeignKeyColumns = array();
            foreach ($foreignKeys as $foreignKey) {
                $allForeignKeyColumns = array_merge($allForeignKeyColumns, $foreignKey->getLocalColumns());
            }

            $pkColumns=array();
            if ($table->hasPrimaryKey()) {
                $pkColumns = $table->getPrimaryKey()->getColumns();
                sort($pkColumns);
            }

            sort($allForeignKeyColumns);

            if ($pkColumns == $allForeignKeyColumns && count($foreignKeys) == 2) {
                $this->manyToManyTables[$tableName] = $table;
            } else {
                // lower-casing is necessary because of Oracle Uppercase Tablenames,
                // assumption is lower-case + underscore separated.
                $className = $this->getClassNameForTable($tableName);
                $this->tables[$tableName] = $table;
                $this->classToTableNames[$className] = $tableName;
            }
        }
    }

3.在同一文件中找到 loadMetadataForClass 方法。修改如下所述的代码。
找到下面陈述的代码：

try {
   $primaryKeyColumns = $this->tables[$tableName]->getPrimaryKey()->getColumns();
} catch(SchemaException $e) {
    $primaryKeyColumns = array();
}

修改如下：

try {
     $primaryKeyColumns = ($this->tables[$tableName]->hasPrimaryKey())?$this->tables[$tableName]->getPrimaryKey()->getColumns():array();
} catch(SchemaException $e) {
     $primaryKeyColumns = array();
}

上述解决方案即使对于没有主键的表也会创建映射（xml / yml / annotation）。

Answer 2

Doctrine要求每个实体类都有一个标识符/主键。

请看这个页面：http://www.doctrine-project.org/docs/orm/2.0/en/reference/basic-mapping.html#identifiers-primary-keys

Answer 3

这种情况是可能的。例如，我将视图映射到模型，视图不是真正的表。在这种情况下，我需要一个模型，不需要主键

没有主键的实体的Symfony Doctrine模型

3 个答案: