【发布时间】：2018-10-29 09:57:46
【问题描述】：
所以我正在快速学习 C# 的方法（继承了这个问题的完整菜鸟）；我编写了以下代码，该代码调用了一个返回 JSON 格式的 Web 服务，该 JSON 格式并不总是正确的。这里的任务是获取 JSON 字符串并将其分解为数组段，然后插入到 SQL 表中以进行进一步的解析和测试。 IE。如果返回字符串类似于
{1234:{5678:{1:{"key":"val","key":"val"},{2:{"key":"val","key":"val"}}}}
那么行将是：
{1234}
{5678}
{1:{"key":"val","key":"val"}
{2:{"key":"val","key":"val"}
这是 .NET 3.0 和 SQL Server 2008 R2（旧版本）。 这是我的工作代码：
public partial class UserDefinedFunctions
{
[Microsoft.SqlServer.Server.SqlFunction(DataAccess =
DataAccessKind.Read)]
public static SqlString TestParse(SqlString uri, SqlString username, SqlString passwd, SqlString postdata)
{
//-----
// The SqlPipe is how we send data back to the caller
SqlPipe pipe = SqlContext.Pipe;
SqlString document;
try
{
// Set up the request, including authentication
WebRequest req = WebRequest.Create(Convert.ToString(uri));
if (Convert.ToString(username) != null & Convert.ToString(username) != "")
{
req.Credentials = new NetworkCredential(
Convert.ToString(username),
Convert.ToString(passwd));
}
((HttpWebRequest)req).UserAgent = "CLR web client on SQL Server";
// Fire off the request and retrieve the response.
using (WebResponse resp = req.GetResponse())
{
using (Stream dataStream = resp.GetResponseStream())
{
//SqlContext.Pipe.Send("...get the data");
using (StreamReader rdr = new StreamReader(dataStream))
{
document = (SqlString)rdr.ReadToEnd();
rdr.Close();
//-----
string connectionString = null;
string sql = null;
connectionString = "Data source= 192.168.0.5; Database=Administration;User Id=Foo;Password=Blah; Trusted_Connection=True;";
using (SqlConnection cnn = new SqlConnection(connectionString))
{
sql = "INSERT INTO JSON_DATA (JSONROW) VALUES(@data)";
cnn.Open();
using (SqlCommand cmd = new SqlCommand(sql, cnn))
{
String payload = "";
String nestpayload = "";
int nests = 0;
String json = document.ToString();
/*first lets do some housekeeping on our payload; double closing curly braces need to be escaped (with curly braces!) in order to keep them in the string.*/
json = json.Replace("\\", "");
int i = json.Length;
//return new SqlString(json);
while (i > 1)
{
/*find the first closing "}" in the string and then check to see if there are more than one.
We need to read the data up to each closing brace, pull off that substring and process it for each iteration until the string is gone.*/
int closingbrace = json.IndexOf("}"); //First closing brace
int nextbrace = Math.Max(0, json.IndexOf("{", closingbrace)); //Next opening brace
String ChkVal = json.Substring(closingbrace + 1, Math.Max(1, nextbrace - closingbrace)); //+1 to ignore the 1st closing brace
int checks = Math.Max(0, ChkVal.Length) - Math.Max(0, ChkVal.Replace("}", "").Length);
payload = json.Substring(0, Math.Max(0, (json.IndexOf("}") + 1)));
/*Remove the payload from the string*/
json = json.Substring(payload.Length + 1);
/*"nests" is how many nested levels excluding the opening brace for the closing brace we found.*/
nests = (payload.Length - payload.Replace("{", "").Length);
/*If we have more then one nest level check to see if any of them go with the payload*/
if (nests > 1)
{
/*Break out the nested section and remove it from the payload.*/
nestpayload = payload.Substring(0, payload.LastIndexOf("{"));
payload = payload.Substring(payload.LastIndexOf("{"), payload.Length - payload.LastIndexOf("{"));
while (nests > 1)
{
if (checks > 0) //# of right braces in payload equals number of left-side nests go with the payload
{
// payload = nestpayload.Substring(Math.Max(0, nestpayload.LastIndexOf("{")), Math.Max(0, nestpayload.Length) - Math.Max(0, (nestpayload.LastIndexOf("{")))) + payload;//The second Math.Max defaults to 1; if we got here there is at minimum one "{" character in the substring
payload = nestpayload.Substring(nestpayload.LastIndexOf("{")) + payload;
nestpayload = nestpayload.Substring(0, Math.Max(0, Math.Max(0, nestpayload.LastIndexOf("{"))));
checks--;
nests--;
}
else
{
/*If we got here there are no more pieces of the nested data to append to the payload.
We use an array and string.split to keep the nest ordering correct.*/
string[] OrderedNest = nestpayload.Split('{');
for (int s = 0; s < OrderedNest.Length; s++)
{
if (OrderedNest[s] != "")
{
cmd.Parameters.AddWithValue("@data", "{" + OrderedNest[s].Replace(":", "}"));
cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
}
}
//cmd.Parameters.AddWithValue("@data", nestpayload.Substring(Math.Max(0,nestpayload.LastIndexOf("{"))).Replace(":","}"));
//cmd.Parameters.AddWithValue("@data", OrderedNest[1].Replace(":","}")+OrderedNest[2]);
// cmd.ExecuteNonQuery();
//cmd.Parameters.Clear();
//nests = Math.Max(0, nests - 1);
nests = 0;
//nestpayload = nestpayload.Substring(0, Math.Max(0, Math.Max(0,nestpayload.LastIndexOf("{"))));
}
}
}
/*At the very end payload will be a single "}"; check for this and discard the last row*/
if (payload != "}")
{
cmd.Parameters.AddWithValue("@data", new SqlChars(payload));
cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
}
/*Get the new string length*/
i = json.Length;
payload = "";
}
}
}
//-----
/* }
catch (Exception e)
{
return e.ToString();
}*/
}
// Close up everything...
dataStream.Close();
}
resp.Close();
// .. and return the output to the caller.
}//end using
return ("Finished");
}
catch (WebException e)
{
throw e;
}
}
}
虽然它有效，但速度非常慢； 4 分钟以上将 1500 行写入服务器。每天一次，这将需要写入约 60,000 条记录；其余时间可能会发布并返回 100 条记录（我还没有完成 POST 部分）。我敢肯定，我在这里做的很多不恰当的事情都会导致问题，但我完全不知道从哪里开始。我很兴奋，我能从中得到正确的回应！任何想法/想法/帮助/同情将不胜感激。
【问题讨论】：
-
首先找出代码的哪一部分花费的时间最多。添加一些测试代码，输出代码各部分的开始和结束时间。我会惊讶地发现对数据库的插入是原因。如果是数据库，那么可能需要对数据库进行碎片整理。您使用的是 SQL Express 还是 SQL Standard？数据库有多大？
-
@jdweng SQL Enterprise。 8个核心。这个特定的数据库是管理性的，非常小。即便如此，它也会定期进行碎片整理。你能帮我一些关于如何输出时间的想法吗？我是将它们输出回 SQL Server 消息窗口还是必须使用调试器和控制台窗口来完成？我安装了 VS2012，当我尝试调试时，我一直收到 MSVMON.EXE 错误。还是没弄明白！
-
我会先删除项目的 bin 文件夹（先复制一份）。这将强制您的所有代码重新编译。 VS 编译器并不总是能够识别库更新，并且您的代码可能与您当前版本的库不完全兼容。我也不喜欢“使用”语句，因为它总是报告异常。我宁愿使用 try/catch 并确保显示所有异常消息。 using 将继续通过没有错误消息的异常，然后您最终在下一个代码块中失败并在错误的代码块中查找错误。
标签： c# sql-server web-services httpwebrequest sqlclr