Question

我在C＃中执行以下语句。有两个表订单，数据。订单是一个mysql数据库。数据是MSSQL数据库。

insert into orders (orders_id, customers_id, customers_cid, customers_vat_id, customers_name, customers_email_address)
select
    o.*
from
    Test.dbo.orders o
where
    not exists (
        select 1
        from
            CobraDemoData.dbo.Data a
        where
            a.email0 = o.customers_email_address
    )

我已经为两个数据库创建了连接字符串

MySqlConnection sqlConn = new MySqlConnection("server=localhost;User Id=root;Password = 123456;Persist Security Info=True;database=xtcommerce";)

SqlConnection con1 = new SqlConnection(@"Data Source=SUBASH-LAPTOP\COBRA;Initial Catalog=CobraDemoData;Integrated Security=True");

你能告诉我下一步该做什么吗？

任何帮助将不胜感激.. 谢谢， Subash ....

Answer 1

打开两个读者，用相同的查询查询两个按相同的键排序的表，然后逐行进行比较，这样的话，（假设有两个连接--mssql和mysql：

var sc1 = mssql.CreateCommand();
var sc2 = mysql.CreateCommand();
sc1.CommandText = sc2.CommandText = "select id, name, email, phone from yourtable ORDER BY Id";
sc1.CommandTimeout = sc2.CommandTimeout = 0;

            using (var r1 = sc1.ExecuteReader())
            {
                using (var r2 = sc2.ExecuteReader())
                {
                    while (true)
                    {
                        bool read1 = r1.Read();

                        if (read1 ^ r2.Read())
                            throw new Exception("Doesn't match!");

                        if(!read1) {Console.WriteLine("MATCH!!!"); break;}

                        for (int i = 0; i < r1.FieldCount; i++)
                        {
                            if (r1.IsDBNull(i) ^ r2.IsDBNull(i))
                                throw new Exception("Doesn't match!");

                            if (string.Compare(r1[i].ToString(), r2[i].ToString(), StringComparison.InvariantCultureIgnoreCase) != 0)
                                throw new Exception("Doesn't match!");

                        }
                    }
                }
            }

然后，您可以基于此示例实现更新逻辑。

<强> BUT

必须有一些唯一字段，用于标识两个表中的行

比较两个表一个是mysql db，一个是MSSQL db

1 个答案: