在理论2中启用IDENTITY_INSERT

Question

我拥有一个mssql数据库服务器，并使用doctrine2(sqlsrv)连接到它。

我想用给定的id创建新的实体实例。但如果我试一试，我会发现一个错误：

Cannot insert explicit value for identity column in table 'my_test_table' when IDENTITY_INSERT is set to OFF

我已经删除了@GeneratedValue注释。但我还是会犯这个错误。

之后，我在“Server管理演播室”中运行了这个脚本：

SET IDENTITY_INSERT my_test_table ON

不幸的是，我还是搞错了，我不明白为什么

Answer 1

它必须以学说的联系为依据

$em->getConnection()->prepare("SET IDENTITY_INSERT my_test_table ON")->execute();

Answer 2

我的设置可能有些不同，或者Doctrine中的某些东西可能已经改变了，但是对于DoctrineORM2.5.6、PHP7.0.17和Server 2014来说，这是行不通的。

尽管在我的同花顺之前设置了它，它还是行不通的。它也不能适用于来自类层次结构的多个表，因为IDENTITY_INSERT一次只能打开一个表。

我能够通过为连接使用包装类来了解如何做到这一点。wrapperClass配置参数支持这一点。下面是我的代码。

<?php
declare(strict_types=1);

namespace Application\Db;

/**
 * Class SqlSrvIdentityInsertConnection
 * This class is to enable Identity Insert when using Doctrine with SQLServer. 
 * Must use this class with the "wrapperClass" configuration option 
 * for EntityManager::create
 */
class SqlSrvIdentityInsertConnection extends \Doctrine\DBAL\Connection
{
    private $tables = [];
    private $enabled = [];

    public function enableIdentityInsertFor(string $tableName)
    {
        $this->tables[] = $tableName;
        $this->enabled[$tableName] = false;
    }

    private function setIdentityInsert(string $statement) {
        // Must turn off IDENTITY_INSERT if it was enabled, and this table
        // isn't in the query. Must do this first!
        foreach($this->tables as $tableName) {
            if (stristr($statement, "INSERT INTO $tableName") === false) {
                if ($this->enabled[$tableName]) {
                    parent::exec("SET IDENTITY_INSERT " . $tableName . " OFF");
                    $this->enabled[$tableName] = false;
                }
            }
        }

        foreach($this->tables as $tableName) {
            if (stristr($statement, "INSERT INTO $tableName") !== false) {
                parent::exec("SET IDENTITY_INSERT ".$tableName." ON");
                $this->enabled[$tableName] = true;

                // Only one can be enabled at a time
                return;
            }
        }
    }

    public function prepare($statement)
    {
        $this->setIdentityInsert($statement);
        return parent::prepare($statement);
    }
}

下面是当您想要将一些实体插入到

    $em->persist($newEntity);

    /** @var SqlSrvIdentityInsertConnection $conn */
    $conn = $em->getConnection();

    $metadata = $this->session->getClassMetaData(MyEntityClass::class);
    $metadata->setIdGeneratorType(ClassMetadata::GENERATOR_TYPE_NONE);
    $conn->enableIdentityInsertFor($metadata->getTableName());

    $em->flush();