Question

使用SQlite处理VisualStudio

我用

创建表格

Dim mainTable = "CREATE TABLE IF NOT EXISTS users (userID INTEGER PRIMARY KEY, type VARCHAR(20))"

Dim tableA = "CREATE TABLE IF NOT EXISTS tableA (partA VARCHAR(20), userID INTEGER, FOREIGN KEY(user) REFERENCES users(userID) ON DELETE CASCADE)"

在我要在级联上删除的子项中，我知道 userIDtoDelete 的值（以前在DataGrid上选择）并且我有这个连接

Dim connDeleteUser =新SQLiteConnection（“Data Source = MyDataBase.sqlite; Version = 3”）

    Try
        Using (connDeleteUser)

            connDeleteUser.Open()


            Dim sql = "DELETE FROM actos WHERE userID = ?"

            Dim connDeleteUser As SQLiteCommand = New SQLiteCommand(sql, connDeleteUser)

            connDeleteUser.CommandText = sql

            connDeleteUser.Parameters.AddWithValue("@userID", userIDtoDelete)

            connDeleteUser.ExecuteNonQuery()

            'I don´t know if this line is neccesary
            connDeleteUser.Close()


        End Using

    Catch ex As Exception
        MsgBox(ex.ToString())
    End Try

我知道我需要声明PRAGMA foreign_keys = ON但我不知道如何

我尝试过这样的事情：

PRAGMA foreign_keys = ON

connDeleteUser.PrepareRetries(@"PRAGMA foreign_keys = ON)

connDeleteUser.CommandText = "PRAGMA foreign_keys = ON"

Dim sql = "DELETE FROM users WHERE userID = ? PRAGMA foreign_keys = ON"

Answer 1

PRAGMA是一个SQL语句;它必须像任何其他SQL语句一样执行：

someCommand.CommandText = "PRAGMA foreign_keys = ON"
someCommand.ExecuteNonQuery

无论如何，您只需将Foreign Keys = True选项添加到连接字符串即可。

如何在VB Net上为SQLite添加PRAGMA foreign_keys = ON？

1 个答案: