Question

所以我用Google搜索并搜索了......是否有一种简单的方法可以将SQL表的表结构与CLR数据表进行比较？

问题在于：我们有一个返回JSON的API，它不断发展。当返回数组包含新对象时，我们希望通知调用者有更多数据可用。

我们可以通过查询轻松获取SQL模式：

select COLUMN_NAME,ORDINAL_POSITION 
from information_schema.columns 
where table_name = 'ApiWork'

但是我们如何将列/序数与持有JSON数组的DataTable进行比较？典型的返回数组如下所示：

 {"Index_0":"930477","Index_1":"test789","ArrayID":"1","Result":"OK","Order_ID":"930477","Model_Number":"FGHB2868TF","Ship_Date":"05/30/2018","Allocated":0,"Backordered":1,"Amount":0}

我们可以使用json反序列化器或循环构建数据表：

DataTable dt = new DataTable();
        SqlPipe pipe = SqlContext.Pipe;
        String d = "";
        String col = "";
        int l = 0;
        int l2 = 0;
        int s = 0;
        int s2 = 0;
        o = "{\"Index_0\":\"930477\",\"Index_1\":\"test789\",\"ArrayID\":\"1\",\"Result\":\"OK\",\"DMI_Order_ID\":\"930477\",\"Model_Number\":\"FGHB2868TF\",\"Ship_Date\":\"05/30/2018\",\"Allocated\":0,\"Backordered\":1,\"Amount\":0}";
        int c = o.Length;
        while (c > 0)
        {
            col = o.Substring(0, o.IndexOf(":")).Replace("\"", "").Replace("{", "").Replace("}", "").Replace("[", "").Replace("]", "");
            dt.Columns.Add(col);
            l = o.IndexOf(":");
            l = l + 1;
            s = o.Length - l;
            o = o.Substring(l,s); // here we have removed the name portion
            l2 = o.IndexOf(",");
            l2 = l2 + 1;
            s2 = o.Length - l2;
            o = o.Substring(l2, s2); // here we have removed the value of the previous name

            c = o.Length;
            if (o.IndexOf(":") == -1 && o.IndexOf(",") == -1)
            {
                c = 0;
            }
        }

我认为像这样循环可以控制序数，如果有必要的话，但正如我在其中一篇评论中提到的那样，这并非完全必要。

Answer 1

所以这似乎只是简单地完成了工作：

  using (SqlCommand command = new SqlCommand("Select name from tempdb.sys.COLUMNS  Where object_id=OBJECT_ID('tempdb.dbo.#ApiWork')EXCEPT Select COLUMN_NAME from INFORMATION_SCHEMA.COLUMNS where table_name = 'ApiWork'"))
            {
                command.Connection = connection;
                using (SqlDataReader reader = command.ExecuteReader())
                {
                    if (reader.HasRows)
                    {
                        pipe.Send("Something is different!");
                    }else{
                        pipe.Send("we're all good!");
                    }

                }
            }

可以检查这两个查询以查看列是否不同。放在一边

COLUMN_ID

和

ORDINAL_ID

可以添加到查询中，然后也可以进行检查。

比较数据表和SQL表

1 个答案: