Heim >Datenbank >MySQL-Tutorial >PHP中实现MySQL嵌套事务的两种解决方案_MySQL
一、问题起源
在MySQL的官方文档中有明确的说明不支持嵌套事务:
代码如下:
Transactions cannot be nested. This is a consequence of the implicit commit performed for any current transaction when you issue a START TRANSACTION statement or one of its synonyms.
代码如下:
当执行一个START TRANSACTION指令时,会隐式的执行一个commit操作。
友情提示,这两个框架的函数和变量的命名都比较的直观,虽然看起来很长,但是都是通过命名就能直接得知这个函数或者变量的意思,所以不要一看到那么一大坨就被吓到了 :)
二、doctrine的解决方案
首先来看下在doctrine中创建事务的代码(干掉了不相关的代码):
代码如下:
public function beginTransaction()
{
++$this->_transactionNestingLevel;
if ($this->_transactionNestingLevel == 1) {
$this->_conn->beginTransaction();
} else if ($this->_nestTransactionsWithSavepoints) {
$this->createSavepoint($this->_getNestedTransactionSavePointName());
}
}
然后看下rollBack函数:
代码如下:
public function rollBack()
{
if ($this->_transactionNestingLevel == 0) {
throw ConnectionException::noActiveTransaction();
}
if ($this->_transactionNestingLevel == 1) {
$this->_transactionNestingLevel = 0;
$this->_conn->rollback();
$this->_isRollbackOnly = false;
} else if ($this->_nestTransactionsWithSavepoints) {
$this->rollbackSavepoint($this->_getNestedTransactionSavePointName());
--$this->_transactionNestingLevel;
} else {
$this->_isRollbackOnly = true;
--$this->_transactionNestingLevel;
}
}
然后我们继续看下commit函数:
代码如下:
public function commit()
{
if ($this->_transactionNestingLevel == 0) {
throw ConnectionException::noActiveTransaction();
}
if ($this->_isRollbackOnly) {
throw ConnectionException::commitFailedRollbackOnly();
}
if ($this->_transactionNestingLevel == 1) {
$this->_conn->commit();
} else if ($this->_nestTransactionsWithSavepoints) {
$this->releaseSavepoint($this->_getNestedTransactionSavePointName());
}
--$this->_transactionNestingLevel;
}
三、laravel的解决方案
laravel的处理方式相对简单粗暴一些,我们先来看下创建事务的操作:
代码如下:
public function beginTransaction()
{
++$this->transactions;
if ($this->transactions == 1)
{
$this->pdo->beginTransaction();
}
}
代码如下:
public function rollBack()
{
if ($this->transactions == 1)
{
$this->transactions = 0;
$this->pdo->rollBack();
}
else
{
--$this->transactions;
}
}
代码如下:
public function commit()
{
if ($this->transactions == 1) $this->pdo->commit();
--$this->transactions;
}