回滚后返回的ExecuteNonQuery的价值(Return value of ExecuteNo

2019-07-20 12:28发布

假设我们有一个存储过程,做喜欢的事,这样的:

BEGIN TRANSACTION
    UPDATE sometable SET aField = 0 WHERE anotherField = 1;       
    UPDATE sometable SET aField = 1 WHERE anotherField = 2;
ROLLBACK TRANSACTION;

而从C#我们有这样的事情:

using (var connection = new SqlConnection("connection string")) 
{
    connection.Open();
    var cmd = connection.CreateCommand();
    cmd.CommandType = CommandType.StoredProcedure;
    cmd.CommandText = "my_procedure";
    var res = cmd.ExecuteNonQuery();                
}

为什么我没有收到获得资源== -1? 我仍然得到受影响的行数。 当文件指出:“如果发生回滚,返回值也为-1”

什么我在这里失踪?

Answer 1:

看来的返回值ExecuteNonQuery是回滚的影响,即使文件中明确指出,就是做。 下面是一些可能的解决方法。

1)使用的ExecuteScalar

SP:

DECLARE @RowCount INT
DECLARE @Error INT

BEGIN TRAN

UPDATE Table1 SET Value1 = NULL

SELECT @RowCount = @@ROWCOUNT, @Error = @@ERROR

IF @Error <> 0 BEGIN
    ROLLBACK TRAN
    SELECT -1
END ELSE BEGIN
    COMMIT TRAN
    SELECT @RowCount
END

C#

using (SqlConnection dbConnection = new SqlConnection("Data Source=.;Initial Catalog=Database1;Integrated Security=True;MultipleActiveResultSets=True"))
{
    dbConnection.Open();

    using (SqlCommand command = dbConnection.CreateCommand())
    {
        command.CommandText = "QuickTest";
        command.CommandType = CommandType.StoredProcedure;

        rowsAffected = command.ExecuteScalar();
    }
}

2)使用返回/输出参数

SP:DECLARE @RowCount INT DECLARE @Error INT

BEGIN TRAN

UPDATE Table1 SET Value1 = NULL

SELECT @RowCount = @@ROWCOUNT, @Error = @@ERROR

IF @Error <> 0 BEGIN
    ROLLBACK TRAN
    RETURN -1
END ELSE BEGIN
    COMMIT TRAN
    RETURN @RowCount
END

C#

using (SqlConnection dbConnection = new SqlConnection("Data Source=.;Initial Catalog=Database1;Integrated Security=True;MultipleActiveResultSets=True"))
{
    dbConnection.Open();

    using (SqlCommand command = dbConnection.CreateCommand())
    {
        command.Parameters.Add(new SqlParameter() {Direction = ParameterDirection.ReturnValue });
        command.CommandText = "QuickTest";
        command.CommandType = CommandType.StoredProcedure;

        command.ExecuteNonQuery();
        rowsAffected = command.Parameters[0].Value;
    }
}

3)将回退/提交逻辑到代码

这将使您能够确定是否发生了回滚和输出必要的-1当值的能力。 交易声明将需要从存储过程中删除。

SP:

UPDATE Table1 SET Value1 = NULL

C#:

using (SqlConnection dbConnection = new SqlConnection("Data Source=.;Initial Catalog=Database1;Integrated Security=True;MultipleActiveResultSets=True"))
{
    dbConnection.Open();

    using (SqlTransaction tran = dbConnection.BeginTransaction())
    {
        using (SqlCommand command = dbConnection.CreateCommand())
        {
            command.Transaction = tran;

            try
            {
                command.Parameters.Add(new SqlParameter() {Direction = ParameterDirection.ReturnValue });
                command.CommandText = "QuickTest";
                command.CommandType = CommandType.StoredProcedure;

                rowsAffected = command.ExecuteNonQuery();
            }

            catch (Exception)
            {
                rowsAffected = -1;
                throw;
            }

            tran.Commit();
        }
    }
}

正如前面提到的,@@ ROWCOUNT值,为ExecuteNonQuery结果都受触发器。



文章来源: Return value of ExecuteNonQuery after rollback