C#从两个表中删除 [英] C# delete from two tables

问题描述

你好，

我想使用C#从两个表中删除一条记录:Comanda和Furnizor与fk cod_furnizor.

Hello,

I want to delete a record from two tables : Comanda and Furnizor with fk cod_furnizor, using C#.

string delete_sql2 = "delete from comanda where cod_furnizor = :cod_furnizor";
string delete_sql1 = "delete from furnizor where cod_furnizor = :cod_furnizor";
OracleCommand cmd2 = new OracleCommand(delete_sql2, connG);
OracleCommand cmd = new OracleCommand(delete_sql1, connG);
cmd2.Parameters.Add(new OracleParameter(":cod_furnizor", Convert.ToInt32(cod)));
cmd.Parameters.Add(new OracleParameter(":cod_furnizor", Convert.ToInt32(cod)));
cmd2.ExecuteNonQuery();
cmd.ExecuteNonQuery();
cmd2.Dispose();
cmd.Dispose();

我试过了，但还是行不通.

[修改:您想使用< pre>标签不是< code>标签]

I tried this, but still doesn`t work.

[Modified: you wanted to use <pre> tags not <code> tags]

推荐答案

是否没有自动交易会导致在代码末尾回滚?

还是有例外?

Isn''t there an automatic transaction which will cause rollback at the end of code?

Or do you have an exception?

不，现在就这些了...

No, this is all for now ...

OracleConnection connG = conexiune.conn;
            try
            {
                foreach (ListViewItem itm in listView1.Items)
                {
                    string cod;
                    if (itm.Checked == true)
                    {
                        cod = itm.Text;
                        string delete_sql1 = "delete from furnizor f, comanda c where f.cod_furnizor = c.cod_furnizor and cod_furnizor = :cod_furnizor";
                        OracleCommand cmd = new OracleCommand(delete_sql1, connG);
                        cmd.Parameters.Add(new OracleParameter(":cod_furnizor", Convert.ToInt32(cod)));
                        cmd.ExecuteNonQuery();
                        cmd.Dispose();
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }

voloda2是正确的:使用Begin Transaction，以便在发生任何故障时回滚.

这是取自 http://download.oracle.com/的示例docs/cd/B28928_01/doc/server.103/b28923/nvadonet.htm

voloda2 is right: Use Begin Transaction so that it will rollback if anything fails.

Here is an example taken from http://download.oracle.com/docs/cd/B28928_01/doc/server.103/b28923/nvadonet.htm

OracleConnection conn = new OracleConnection ("DSN=consroot;uid=system");
conn.Open();
IDbTransaction trans = conn.BeginTransaction(); // Turn off AUTOCOMMIT
OracleCommand cmd = (OracleCommand)conn.CreateCommand();
cmd.CommandText = "create table TEST1 (c0 number)";
cmd.ExecuteNonQuery();
trans.Commit(); // AutoCommit is ''ON''
cmd.Dispose();
conn.Close();

它在文章中指出，默认情况下它设置为自动提交，这也是我在mysql上的经验.这样可以避免这种情况的发生.

It states in the article that by default it is set to auto commit which has been my experience with mysql as well. This will prevent that from happening.

这篇关于C#从两个表中删除的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！