C# 4.0 NpqsqlParameter-多个值

代码：

string sqlCommand = @"UPDATE table SET active = 0 WHERE id IN (@CommaSeparatedId)";
string sqlParamName = "CommaSeparatedId";
string sqlParamValue = "111, 222";

try
{
    using (NpgsqlConnection connection = new NpgsqlConnection())
    {
        // Get connection string from Web.config
        connection.ConnectionString = _connectionString;
        connection.Open();
        Int32 rowsAffected;

        using (NpgsqlCommand command = new NpgsqlCommand(sqlCommand, connection))
        {
            NpgsqlParameter sqlParam = new NpgsqlParameter(sqlParamName, NpgsqlTypes.NpgsqlDbType.Varchar);
            // Code below no exception occur, and active not updated to 0
            // sqlParam.Value = sqlParamValue;

            // This code works for only one value
            sqlParam.Value = "111";

            command.Parameters.Add(sqlParam);
            rowsAffected = command.ExecuteNonQuery();
        }
    }
}
catch (NpgsqlException pgEx)
{
    throw pgEx;
}

UPDATE table
    SET active = 0
WHERE id IN ('111', '222');

---

问题是：

string sqlCommand = @"UPDATE table SET active = 0 WHERE id IN (@CommaSeparatedId)";
string sqlParamName = "CommaSeparatedId";
string sqlParamValue = "111, 222";

try
{
    using (NpgsqlConnection connection = new NpgsqlConnection())
    {
        // Get connection string from Web.config
        connection.ConnectionString = _connectionString;
        connection.Open();
        Int32 rowsAffected;

        using (NpgsqlCommand command = new NpgsqlCommand(sqlCommand, connection))
        {
            NpgsqlParameter sqlParam = new NpgsqlParameter(sqlParamName, NpgsqlTypes.NpgsqlDbType.Varchar);
            // Code below no exception occur, and active not updated to 0
            // sqlParam.Value = sqlParamValue;

            // This code works for only one value
            sqlParam.Value = "111";

            command.Parameters.Add(sqlParam);
            rowsAffected = command.ExecuteNonQuery();
        }
    }
}
catch (NpgsqlException pgEx)
{
    throw pgEx;
}

UPDATE table
    SET active = 0
WHERE id IN ('111', '222');

如果我使用

111、222

作为

sqlParam.Value'

rowsAffected=0

，但如果我只使用
111
或
222
rowsAffected=1`。这意味着仅更新1个值会成功，但如果尝试更新多个值则会失败


预期查询：

string sqlCommand = @"UPDATE table SET active = 0 WHERE id IN (@CommaSeparatedId)";
string sqlParamName = "CommaSeparatedId";
string sqlParamValue = "111, 222";

try
{
    using (NpgsqlConnection connection = new NpgsqlConnection())
    {
        // Get connection string from Web.config
        connection.ConnectionString = _connectionString;
        connection.Open();
        Int32 rowsAffected;

        using (NpgsqlCommand command = new NpgsqlCommand(sqlCommand, connection))
        {
            NpgsqlParameter sqlParam = new NpgsqlParameter(sqlParamName, NpgsqlTypes.NpgsqlDbType.Varchar);
            // Code below no exception occur, and active not updated to 0
            // sqlParam.Value = sqlParamValue;

            // This code works for only one value
            sqlParam.Value = "111";

            command.Parameters.Add(sqlParam);
            rowsAffected = command.ExecuteNonQuery();
        }
    }
}
catch (NpgsqlException pgEx)
{
    throw pgEx;
}

UPDATE table
    SET active = 0
WHERE id IN ('111', '222');


我在上面的代码中缺少了什么？
您所面临的问题是，数据库引擎将看到参数值“111222”，而不是两个不同的值，而是一个。

数据库将搜索ID为“111222”的记录，但未找到与请求匹配的内容。

您应该尝试使用存储过程，并根据PostgreSQL所需的语法执行正确的。从您的代码中，发送sql（如果启用它，可以在Postgresql日志中看到）如下所示：updatetablesetactive=0，其中id位于（'111222'）；我们有一个功能请求，正是为了满足您一次添加多个值的需要，但我们没有实现它，而且我们认为它不会实现，因为这种逗号分隔的处理应该由上层的某个东西来完成，可能由ORM来完成。只是在我们的跟踪器中找到了该功能请求。在那里你可能会发现一些关于如何解决这个问题的有用信息：我希望它能有所帮助。