使用自动增量列

Question

我有 12 列，第一列作为主键和自动增量。所以在我的插入命令中，我传递了 11 个值，但我不断收到错误消息，表有 12 列，但提供了 11 个值。

这里是创建表语句：

public String CREATE_TABLE = "CREATE TABLE coupons"
    + "(sno INTEGER PRIMARY KEY AUTOINCREMENT, "
                             + "title VARCHAR(20), " +
                             "description VARCHAR(20), " +
                             "imagepath VARCHAR(20), " +
                             "couponpath VARCHAR(20), " +
                             "barcodepath VARCHAR(20), " +
                             "downloadedon VARCHAR(20), "
                             + "redeemedon VARCHAR(20), " + "starttime VARCHAR(20), " + "endtime VARCHAR(20), "
                             + "status VARCHAR(20), statustext VARCHAR(20))";

这是我的插入语句：

    String insertString = "INSERT INTO coupons VALUES(@title, @description, @imagepath, @couponpath, @barcodepath, @downloadedon, @redeemedon, @starttime, @endtime, @status, @statustext)";

    SqliteCommand command = new SqliteCommand (insertString, m_dbConnection);
    command.Parameters.AddWithValue ("@title", title);
    command.Parameters.AddWithValue ("@description", description);
    command.Parameters.AddWithValue ("@imagepath", imagepath);
    command.Parameters.AddWithValue ("@couponpath", couponpath);
    command.Parameters.AddWithValue ("@barcodepath", barcodepath);
    command.Parameters.AddWithValue ("@downloadedon", downloadedon);
    command.Parameters.AddWithValue ("@redeemedon", redeemedon);
    command.Parameters.AddWithValue ("@starttime", starttime);
    command.Parameters.AddWithValue ("@endtime", endtime);
    command.Parameters.AddWithValue ("@status", status);
    command.Parameters.AddWithValue ("@statustext", statustext);

    command.ExecuteNonQuery ();

How to increment an auto-increment field with ADO.NET in C# 似乎有帮助，但没有用。我做错了什么？

我做错了什么？

在使用插入语句时，您必须提及所有其他列名，除了 Autoincrement 列。

我现在的插入语句：

    String insertString = @"INSERT INTO coupons(title, description, imagepath, couponpath, barcodepath, downloadedon, redeemedon, starttime, endtime, status, statustext) VALUES(@title, @description, @imagepath, @couponpath, @barcodepath, @downloadedon, @redeemedon, @starttime, @endtime, @status, @statustext)";

即使这样也有效：

String insertString = @"INSERT INTO coupons VALUES(NULL, @title, @description, @imagepath, @couponpath, @barcodepath, @downloadedon, @redeemedon, @starttime, @endtime, @status, @statustext)";

编辑：

现在错误消失了，但是当我从表中检索 sno 时，我没有看到任何值。

Sno:    Title: Sprint Customer Feedback Campaign

如您所见，Sno 是空的。为什么会这样？

这是我从 db 读取数据的方式..

public void getDataFromTable ()
{

    string selectString = "select * from coupons";
    SqliteCommand command = new SqliteCommand (selectString, m_dbConnection);
    SqliteDataReader reader = command.ExecuteReader ();
    while (reader.Read ()) {
        Console.WriteLine ("Sno: " + reader ["sno"] +
        "\tTitle: " + reader ["title"] +
        "\tDescription: " + reader ["description"] +
        "\tImagePath: " + reader ["imagepath"] +
        "\tCouponPath: " + reader ["couponpath"] +
        "\tBarcodePath: " + reader ["barcodepath"] +
        "\tDownloadedOn: " + reader ["downloadedon"] +
        "\tRedeemedOn: " + reader ["redeemedon"] +
        "\tStartTime: " + reader ["starttime"] +
        "\tEndTime: " + reader ["endtime"] +
        "\tStatus: " + reader ["status"] +
        "\tStatusText: " + reader ["statustext"]
        );
    }
    Console.ReadLine ();
}

Answer 1

在您的情况下，正确的插入查询如下所示：

String insertString = @"INSERT INTO coupons(title, description, imagepath, couponpath, barcodepath, downloadedon, redeemedon, starttime, endtime, status, statustext)
VALUES(@title, @description, @imagepath, @couponpath, @barcodepath, @downloadedon, @redeemedon, @starttime, @endtime, @status, @statustext)";

如果不是所有列都在插入中受影响，您必须明确列出所有列。省略列列表意味着您必须插入所有列。

Answer 2

Hamlet Hakobyan 有一个解决方案，但还有另一种方法：

如果将NULL 插入INTEGER PRIMARY KEY 列，则row id autogeneration kicks in。所以保留代码并将NULL添加到这里的SQL中：

String insertString = "INSERT INTO coupons VALUES(NULL, @title, @description, @imagepath, @couponpath, @barcodepath, @downloadedon, @redeemedon, @starttime, @endtime, @status, @statustext)";