Question

我有一个奇怪的用例，说明我们如何在一段代码中处理SQL连接。为了测试这个，我创建了一个单元测试：

var masterBuilder = new SqlConnectionStringBuilder("Server=CHILTERN8564;Integrated Security=SSPI");
var databaseBuilder = new SqlConnectionStringBuilder(masterBuilder.ConnectionString);
databaseBuilder.InitialCatalog = "CoreIssue";

using (var conDatabase = new SqlConnection(databaseBuilder.ConnectionString))
{
    Assert.Throws<SqlException>(conDatabase.Open); // crash as DB does not exist
}

using (var conMaster = new SqlConnection(masterBuilder.ConnectionString))
{
    // let's create the DB
    conMaster.Open();
    new SqlCommand("CREATE DATABASE CoreIssue", conMaster).ExecuteNonQuery();
}

using (var conDatabase = new SqlConnection(databaseBuilder.ConnectionString))
{
    // CRASH! even if the DB exists.
    conDatabase.Open();
    new SqlCommand("CREATE TABLE Bob(name varchar(10))", conDatabase).ExecuteNonQuery();
}

基本上在第一次连接抛出后因为DB不存在，最后一个抛出也是，显然是因为DB处于＆＃34;破坏＆＃34;状态？

如果我删除第一个using块，一切正常，如果我调试并缓慢地逐步执行代码（在最后一次查询之前等待几秒钟），一切正常。

有关可能导致此行为的任何想法吗？

Answer 1

所以MultipleActiveResultSets没有帮助但是如果你设置了我找到了两个解决方案：

databaseBuilder.Pooling = false;

或致电

SqlConnection.ClearAllPools();

所以测试将是：

[Test]
public void Test()
{
    var masterBuilder = new SqlConnectionStringBuilder(@"Server=localhost\sqlexpress;Integrated Security=SSPI");
    var databaseBuilder = new SqlConnectionStringBuilder(masterBuilder.ConnectionString);
    databaseBuilder.InitialCatalog = "CoreIssue";
    //databaseBuilder.Pooling = false; <- fixes problem

    using (var conDatabase = new SqlConnection(databaseBuilder.ConnectionString))
    {
        Assert.Throws<SqlException>(conDatabase.Open); // crash as DB does not exist
    }

    SqlConnection.ClearAllPools(); //<- also fixes problem

    using (var conMaster = new SqlConnection(masterBuilder.ConnectionString))
    {
        // let's create the DB
        conMaster.Open();
        new SqlCommand("CREATE DATABASE CoreIssue", conMaster).ExecuteNonQuery();
    }

    using (var conDatabase = new SqlConnection(databaseBuilder.ConnectionString))
    {
        // CRASH! even if the DB exists.
        conDatabase.Open();
        new SqlCommand("CREATE TABLE Bob(name varchar(10))", conDatabase).ExecuteNonQuery();
    }

显然，这并没有真正解释为什么崩溃的连接在游泳池中并且重复使用...

SQL Server连接错误会阻止后续连接

1 个答案: