C# 中的 Oracle、绑定变量和 ID IN (1, 2, 3) 等查询

我正在寻找以下 Java 技术的 C# ODAC 改编，其中代码能够将数字数组（数组大小可以变化）绑定到非 PL/SQL 中SELECT语句，然后在 a 中使用结果数组WHERE ID IN (...)风格检查。

http://rafudb.blogspot.com/2011/10/variable-inlist.html http://rafudb.blogspot.com/2011/10/variable-inlist.html

下面是基于 OCI 的 C 程序中使用此技术的另一个示例：

Oracle OCI、绑定变量和 ID IN (1, 2, 3) 等查询 https://stackoverflow.com/questions/18603281/oracle-oci-bind-variables-and-queries-like-id-in-1-2-3

具体来说，我们想要执行如下查询

SELECT * FROM MyTable WHERE ID IN (SELECT * FROM TABLE(:1))

并将数字数组传入:1.

Code:

oraParam.UdtTypeName = "SYS.ODCINUMBERLIST";
VArray newArray = new VArray();
newArray.Array = new Int32[] {12,24,42};
oraParam.OracleDbType = OracleDbType.Array;
oraParam.Value = newArray;

string query = @"Select * from TABLE(:1) ";
OracleCommand command = new OracleCommand(query, MyConnection);
command.Parameters.Add(oraParam);
OracleDataReader reader;
var m_connection = new OracleConnection("The CONNECTION STRING");
m_connection.Open();
var reader = command.ExecuteReader();
reader.Close();
m_connection.Close();

接下来是以下辅助类：

class VArray : IOracleCustomType, INullable
{
    [OracleArrayMapping()]
    public Int32[] Array;

    private OracleUdtStatus[] m_statusArray;
    public OracleUdtStatus[] StatusArray
    {
        get
        {
            return this.m_statusArray;
        }
        set
        {
            this.m_statusArray = value;
        }
    }

    private bool m_bIsNull;

    public bool IsNull
    {
        get
        {
            return m_bIsNull;
        }
    }

    public static VArray Null
    {
        get
        {
            VArray obj = new VArray();
            obj.m_bIsNull = true;
            return obj;
        }
    }

    public void ToCustomObject(OracleConnection con, IntPtr pUdt)
    {
        object objectStatusArray = null;
        Array = (Int32[])OracleUdt.GetValue(con, pUdt, 0, out objectStatusArray);
        m_statusArray = (OracleUdtStatus[])objectStatusArray;
    }

    public void FromCustomObject(OracleConnection con, IntPtr pUdt)
    {
        OracleUdt.SetValue(con, pUdt, 0, Array, m_statusArray);
    }

    public override string ToString()
    {
        if (m_bIsNull)
            return "VArray.Null";
        else
        {
            string rtnstr = String.Empty;
            if (m_statusArray[0] == OracleUdtStatus.Null)
                rtnstr = "NULL";
            else
                rtnstr = Array.GetValue(0).ToString();
            for (int i = 1; i < m_statusArray.Length; i++)
            {
                if (m_statusArray[i] == OracleUdtStatus.Null)
                    rtnstr += "," + "NULL";
                else
                    rtnstr += "," + Array.GetValue(i).ToString();
            }
            return "VArray(" + rtnstr + ")";
        }
    }
}

[OracleCustomTypeMapping("SYS.ODCINUMBERLIST")]
public class VArrayFactory : IOracleCustomTypeFactory, IOracleArrayTypeFactory
{
    // IOracleCustomTypeFactory
    public IOracleCustomType CreateObject()
    {
        return new VArray();
    }

    // IOracleArrayTypeFactory Interface
    public Array CreateArray(int numElems)
    {
        return new Int32[numElems];
    }

    public Array CreateStatusArray(int numElems)
    {
        // CreateStatusArray may return null if null status information 
        // is not required.
        return new OracleUdtStatus[numElems];
    }
}

描述：

总体思路是，与 OCI 示例类似，您必须将参数强制转换为 SYS.ODCINUMBERLIST（或其他有效类型）。默认情况下，C# OracleDBType 中未定义该类型，因此您必须使用 UdtTypeName 和自定义工厂/类才能成功绑定。

这是受到启发的以下关于定义自定义类型的文章 http://www.codeproject.com/Articles/33829/How-to-use-Oracle-11g-ODP-NET-UDT-in-an-Oracle-Sto.

Limits:

此精确解决方案仅适用于 INT/NUMBER 值，因为它搭载了 SYS.ODCINUMBERLIST 表类型。如果其他类型需要它，您可能需要查找/编写其他自定义表类型。