C# 如何将每500个员工id发送到Oracle以解决ORA-07195问题

我已经有了为每个员工生成stringBuilder的代码，我从另一个表中获取了所有employeesId。但是如果我有超过1000名员工，我会得到错误ORA-07195，我知道这个错误与列表中的最大表达式有关。因此，如何将每500名员工发送到数据访问对象中的查询

Public List<GraphModel> countRequestCreatedByTypeDefaulPage(int year, int month, String employeeID)
    {
        int count = 0;
        int countEmployeess = 0;
        string employeesid = "";

        DataView dv = _employeeOverrideBO.getRelatedEmployees(year, month, employeeID);
        StringBuilder listEmployees = new StringBuilder();

        for (int i = 0; i < countEmployees; i += 500) 
        {

        foreach (DataRowView rowView in dv)
        {
            DataRow row = rowView.Row;
            String employee = row["EMPLOYEE_ID"].ToString();
            if (count > 0)
                listEmployees.Append(",");
            listEmployees.Append("'").Append(employee).Append("'"); 
            count++;
        }

        }
        countEmployeess++;
        employeesid = listEmployees.ToString();

        return _requestDAO.countRequestCreatedByTypeDefaulPage(employeesid);

Public List countRequestCreatedByTypeDefaulPage（整数年、整数月、字符串employeeID）
{
整数计数=0；
int countEmployeess=0；
字符串employeesid=“”；
DataView dv=_employeeOverrideBO.getRelatedEmployees（年、月、employeeID）；
StringBuilder listEmployees=新建StringBuilder（）；
对于（int i=0；i0）
listEmployees.追加（“，”）；
listEmployees.Append（“”）。Append（employee.Append（“”）；
计数++；
}
}
countEmployeess++；
employeesid=listEmployees.ToString（）；
返回_requestDAO.countRequestCreatedByTypeDefaulPage（employeesid）；

这也是我在数据访问对象中的查询

public List<GraphModel> countRequestCreatedByTypeDefaulPage(string employeesIds)
    {
        String sql = " select NVL(TO_CHAR(RR.REASON_NM_NEW), 'Total') as SERIES1, count(*) AS VAL" +
                     " from REQUEST R, REQUEST_PERSON RP, REQUEST_REASON RR " +
                     " WHERE R.STATUS IN ('CREATED', 'PENDING APPROVAL', 'APPROVED BY MANAGER', 'APPROVED', 'IN PROCESS') " +
                     " AND R.REQUEST_ID = RP.REQUEST_ID" +
                     " AND RP.REQUEST_ROLE = 'REQUESTOR' " +
                     " AND RR.REASON_ID = R.REASON_ID" +
                     " AND RP.EMPLOYEE_ID IN (" + employeesIds + ") " +
                     " group by rollup (RR.REASON_NM_NEW) " + 
                     " ORDER BY count(*)  DESC";
        OracleCommand cmd = new OracleCommand(sql);


        try
        {
            DataTable dataTable = Data_base_Access.executeSQL(cmd, ConfigurationManager.ConnectionStrings["stage"].ToString());
            return (GraphModel.convertToList(dataTable));
        }
        catch (Exception ex)
        {
            Log.writeError("Request DAO", ex);
            throw new DataAccessException("There was an error counting the open requests");
        }
    }

public List countRequestCreatedByTypeDefaulPage（字符串employeesIds）
{
String sql=“选择NVL（TO_CHAR（RR.REASON_NM_NEW），'Total'）作为SERIES1，count（*）作为VAL”+
“来自请求R、请求人RP、请求原因RR”+
“其中R.状态为（‘已创建’、‘待批准’、‘已经理批准’、‘已批准’、‘正在进行’）”+
“和R.REQUEST\u ID=RP.REQUEST\u ID”+
“和RP.REQUEST_ROLE='REQUESTOR'”+
“和RR.REASON\u ID=R.REASON\u ID”+
“和RP.EMPLOYEE_ID在（“+employeesIds+”）中”+
“分组汇总（RR.REASON\u NM\u NEW）”+
“按计数排序（*）说明”；
OracleCommand cmd=新的OracleCommand（sql）；
尝试
{
DataTable DataTable=Data_base_Access.executeSQL（cmd，ConfigurationManager.connectionString[“stage”].ToString（））；
返回（GraphModel.convertToList（dataTable））；
}
捕获（例外情况除外）
{
Log.writeError（“请求DAO”，ex）；
抛出新的DataAccessException（“计算打开的请求时出错”）；
}
}

此查询还获取名为GraphModel的列表计数

     public static List<GraphModel> convertToList(System.Data.DataTable dataTable)
    {
        List<GraphModel> list = new List<GraphModel>();
        foreach (DataRow dtRow in dataTable.Rows)
        {
            list.Add(convertToGraphModel(dtRow));
        }
        return list;
    }

    public static GraphModel convertToGraphModel(DataRow dtRow)
    {

        GraphModel graphModel = new GraphModel();

        if (dtRow.Table.Columns.Contains("SERIES1") && dtRow["SERIES1"] != DBNull.Value)
        {
            graphModel.SERIES1 = Convert.ToString(dtRow["SERIES1"]);
        }

        if (dtRow.Table.Columns.Contains("SERIES2") && dtRow["SERIES2"] != DBNull.Value)
        {
            graphModel.SERIES2 = Convert.ToString(dtRow["SERIES2"]);
        }

        if (dtRow.Table.Columns.Contains("VAL") && dtRow["VAL"] != DBNull.Value)
        {
            graphModel.VAL = Convert.ToInt32(dtRow["VAL"]);
        }


        return graphModel;
    }
}

公共静态列表转换器列表（System.Data.DataTable）
{
列表=新列表（）；
foreach（dataTable.Rows中的DataRow dtRow）
{
list.Add（convertToGraphModel（dtRow））；
}
退货清单；
}
公共静态图形模型convertToGraphModel（DataRow dtRow）
{
GraphModel GraphModel=新GraphModel（）；
if（dtRow.Table.Columns.Contains（“SERIES1”）和&dtRow[“SERIES1”！=DBNull.Value）
{
graphModel.SERIES1=Convert.ToString（dtRow[“SERIES1]”）；
}
if（dtRow.Table.Columns.Contains（“SERIES2”）和&dtRow[“SERIES2”！=DBNull.Value）
{
graphModel.SERIES2=Convert.ToString（dtRow[“SERIES2]”）；
}
if（dtRow.Table.Columns.Contains（“VAL”）和&dtRow[“VAL”！=DBNull.Value）
{
graphModel.VAL=Convert.ToInt32（dtRow[“VAL”]）；
}
返回图形模型；
}
}

---

我非常感谢您的帮助，因为我正在进行大量研究，我不知道我能做些什么

将列表拆分为1000个项目列表，并将查询更改为：

" AND (RP.EMPLOYEE_ID IN (" + ids_1_1000 + ") OR RP.EMPLOYEE_ID IN (" + ids_1001_2000 + "))" +

---

我最喜欢Oracle的一个功能是Oracle调用接口（OCI），它允许您使用编程语言访问Oracle的一些更强大的功能。特别是在本例中，大容量插入的功能应该非常有用

如果不采用上面的方法，即在一条SQL语句中插入数千个文本，而是将这些值放入一个表中并进行连接，我认为您将：

使共享池不必编译非常糟糕的SQL语句

无需转义字符串或担心SQL注入

有一个闪电般快速的查询，用一个连接（面包和黄油代替数据库）来代替列表中的一个巨人

步骤1：创建GTT：

create global temporary table employee_list (
  employee_id varchar2(100) not null
) on commit preserve rows;

GTT基于一个会话，因此，即使您在多个实例中运行此代码，每个GTT都将充当每个实例的一张白板——不存在数据冲突的可能性

步骤2：在您的代码中，创建一个

事务

，以处理您需要在表中插入和选择数据作为同一事务的一部分：

OracleTransaction trans = conn.BeginTransaction(IsolationLevel.ReadCommitted);

步骤3：使用ODP.net的批量插入功能一次插入所有员工ID。我鼓励您对此进行基准测试，而不是一次插入一个。你会惊讶的。如果你有50000多个字段，那么你可能需要将这些字段分为多个块，但对于单个字段，我认为这应该足够了：

// string[] employeesIds

OracleCommand cmd = new OracleCommand("insert into employee_list values (:EMPLOYEE)",
    conn);
cmd.Transaction = trans;
cmd.Parameters.Add(new OracleParameter("EMPLOYEE", OracleDbType.Varchar2));
cmd.Parameters[0].Value = employeesIds;
cmd.ArrayBindCount = employeesIds.Length;
cmd.ExecuteNonQuery();

注意

employeeid

应该是一个数组

步骤4：将SQL从in列表更改为join：

 select NVL(TO_CHAR(RR.REASON_NM_NEW), 'Total') as SERIES1, count(*) AS VAL
 from
   REQUEST R,
   REQUEST_PERSON RP,
   REQUEST_REASON RR,
   employee_list e       -- added this
 WHERE R.STATUS IN ('CREATED', 'PENDING APPROVAL', 'APPROVED BY MANAGER',
     'APPROVED', 'IN PROCESS')
 AND R.REQUEST_ID = RP.REQUEST_ID
 AND RP.REQUEST_ROLE = 'REQUESTOR'
 AND RR.REASON_ID = R.REASON_ID
 AND RP.EMPLOYEE_ID = e.employee_id  -- changed this
 group by rollup (RR.REASON_NM_NEW)
 ORDER BY count(*)  DESC

下面是这一切在一起的样子：

public List<GraphModel> countRequestCreatedByTypeDefaulPage(string[] employeesIds)
{
    OracleTransaction trans = conn.BeginTransaction(IsolationLevel.ReadCommitted);
    OracleCommand cmd = new OracleCommand("insert into employee_list values (:EMPLOYEE)",
        conn);
    cmd.Transaction = trans;
    cmd.Parameters.Add(new OracleParameter("EMPLOYEE", OracleDbType.Varchar2));
    cmd.Parameters[0].Value = employeesIds;
    cmd.ArrayBindCount = employeesIds.Length;
    cmd.ExecuteNonQuery();

    String sql = "";  // code from above goes here

    cmd = new OracleCommand(sql, conn);
    cmd.Transaction = trans;

    DataTable dataTable = null;

    try
    {
        dataTable = Data_base_Access.executeSQL(cmd,
            ConfigurationManager.ConnectionStrings["stage"].ToString());
        return (GraphModel.convertToList(dataTable));
    }
    catch (Exception ex)
    {
        Log.writeError("Request DAO", ex);
        throw new DataAccessException("There was an error counting the open requests");
    }
    finally
    {
        trans.Rollback();
    }

    return dataTable;
}

public List countRequestCreatedByTypeDefaulPage（字符串[]employeesIds）
{
OracleTransaction=conn.BeginTransaction（IsolationLevel.ReadCommitted）；
OracleCommand cmd=新的OracleCommand（“插入员工列表值（：员工）”，
康涅狄格州）；
cmd.Transaction=trans；
Add（新的OracleParameter（“EMPLOYEE”，OracleDbType.Varchar2））；
cmd.Parameters[0]。Value=employeesIds；
cmd.ArrayBindCount=employeesIds.Length；
cmd.ExecuteNonQuery（）；
字符串sql=“”；//上面的代码在这里
cmd=新的OracleCommand（sql，conn）；
public List<GraphModel> countRequestCreatedByTypeDefaulPage(int year, int month, String employeeID)
    {
        int count = 0;
        int countEmployees = 0;
        Dictionary<string, int> dataChart = new Dictionary<string, int>();
        DataView dv = _employeeOverrideBO.getRelatedEmployeesRequests(year, month, employeeID);
        StringBuilder listEmployees = new StringBuilder();

        foreach (DataRowView rowView in dv) 
        {
            if (countEmployees == 500)
            {
                List<GraphModel> listReturn = _requestDAO.countRequestCreatedByTypeDefaulPage(listEmployees.ToString());

                foreach(GraphModel model in listReturn){

                    if (dataChart.ContainsKey(model.SERIES1))
                    {
                        dataChart[model.SERIES1] = dataChart[model.SERIES1] + model.VAL;
                    }
                    else
                    {
                        dataChart[model.SERIES1] = model.VAL;
                    }

                }
                listEmployees = new StringBuilder();
                count = 0;
                countEmployees = 0;
            }

            DataRow row = rowView.Row;
            String employee = row["EMPLOYEE_ID"].ToString();
            if (count > 0)
                listEmployees.Append(",");
            listEmployees.Append("'").Append(employee).Append("'");
            count++;

            countEmployees++;

        }

        //Last Call
        List<GraphModel> listReturnLast = _requestDAO.countRequestCreatedByTypeDefaulPage(listEmployees.ToString());
        foreach (GraphModel model in listReturnLast) {

            if (dataChart.ContainsKey(model.SERIES1))
            {
                dataChart[model.SERIES1] = dataChart[model.SERIES1] + model.VAL;
            }
            else
            {
                dataChart[model.SERIES1] = model.VAL;
            }

        }




        List<GraphModel> list = new List<GraphModel>();
        foreach (KeyValuePair<string, int> entry in dataChart)
        {
            GraphModel model = new GraphModel();
            model.SERIES1 = entry.Key;
            model.VAL = entry.Value;
            list.Add(model);
        }

        return list;
    }