Question

我有一个users表，一个categories表和一个user_category表作为pivot。我想从类别表中选择多个ID，然后生成一个查询，该查询仅显示不属于所选类别之一的用户的记录。

因此，如果用户是两个类别的成员，并且我选择在我的“不是”中排除其中一个类别。查询，它们不会出现在我的结果中。

这就是我现在所拥有的：

select distinct users.id, users.firstname, users.lastname, users.email from users INNER JOIN user_category ON users.id = user_category.user_id WHERE user_category.category_id NOT IN (280, 210, 177, 207, 240, 157, 187, 246, 153, 208, 199, 156, 281, 211, 212, 220, 218, 170, 201, 222, 236, 233)

问题是，如果用户属于类别280并且也是我没有选择的类别之一，他们仍然会出现。

Answer 1

Public Class Form1
    Private DrawHighlightingRectangle As Boolean = True
    Private HighlightingRectangleColour As Color = Color.Red
    Private PenWidth = 1
    Dim myPen As New System.Drawing.Pen(HighlightingRectangleColour, PenWidth)

    Dim x = 0

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Text = "Pen Width = " & PenWidth & ", X = " & x
        myPen.Alignment = Drawing2D.PenAlignment.Inset
    End Sub

    Private Sub Form1_Paint(sender As Object, e As PaintEventArgs) Handles Me.Paint
        If DrawHighlightingRectangle Then
            e.Graphics.Clear(Me.BackColor)
            e.Graphics.DrawLine(myPen, x, 100, x, 200)
            e.Graphics.DrawLine(myPen, CInt(Math.Floor(PenWidth / 2)), 10, CInt(Math.Floor(PenWidth / 2)), 100)
        End If
    End Sub

    Private Sub Form1_Resize(sender As Object, e As EventArgs) Handles Me.Resize
        Me.Invalidate()
        Me.Update()
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click ' draw button
        DrawHighlightingRectangle = Not DrawHighlightingRectangle
        Me.Invalidate()
        Me.Update()
    End Sub

    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click ' Move Right
        x += 1
        Text = "Pen Width = " & PenWidth & ", X = " & x
        Me.Invalidate()
        Me.Update()
    End Sub

    Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click ' increase pen width
        PenWidth += 1
        myPen.Dispose()
        myPen = New System.Drawing.Pen(HighlightingRectangleColour, PenWidth)
        Text = "Pen Width = " & PenWidth & ", X = " & x
        Me.Invalidate()
        Me.Update()
    End Sub

    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click ' reset width and X
        PenWidth = 1
        x = 0
        myPen.Dispose()
        myPen = New System.Drawing.Pen(HighlightingRectangleColour, PenWidth)
        Text = "Pen Width = " & PenWidth & ", X = " & x
        Me.Invalidate()
        Me.Update()
    End Sub

    Private Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click ' Move Left
        x -= 1
        Text = "Pen Width = " & PenWidth & ", X = " & x
        Me.Invalidate()
        Me.Update()
    End Sub
End Class

MySQL数据透视表 - 仅显示A中不存在于B列表中的ID的记录

1 个答案: