Question

我想从<DllImport("user32.dll")> _ Public Shared Function SetForegroundWindow(hWnd As IntPtr) As Boolean End Function Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click ` AutoSaveTimer.Enabled = True Try 'Find the handle to the game. This can do it by searching for the process. Dim p As System.Diagnostics.Process() = System.Diagnostics.Process.GetProcessesByName("notepad") 'search for process notepad If p.Length > 0 Then 'check if window was found 'bring notepad to foreground SetForegroundWindow(p(0).MainWindowHandle) End If System.Threading.Thread.Sleep(50) GameConnection.SendKeyTo(Keys.OemSemicolon) System.Threading.Thread.Sleep(2000) GameConnection.SendKeyTo(Keys.K) System.Threading.Thread.Sleep(50) GameConnection.SendKeyTo(Keys.Enter) Catch AutoSaveExeption As GameException If AutoSaveExeption.GameErrorCode = GameError.GAME_ERR_SENDMSG Then ' Send message error - connection to Game lost. ' MessageBox.Show("cant make a connection.... can't autosave sadly", AppTitle, MessageBoxButtons.OK, MessageBoxIcon.Exclamation) SimConnectionBar.BackColor = Color.Red End If End Try end sub表中选择12个帖子。如果没有12个，我需要从posts表中选择缺失。

parchive

错误：
$stmt = $db->query("SELECT * FROM posts where status='public' and user='public' order by inde asc limit 12 offset " . $offset); $count1 = $stmt->rowCount(); if ($count1 < 12){ $diff = 12 - $count1; $stmt = $db->query("SELECT * FROM posts where status='public' and user='public' order by inde asc limit 12 offset " . $offset . " union select * from parchive where status='public' order by date desc limit " . $diff); }

任何帮助？

Answer 1

如果你需要限制和订单选择联合添加几个（）围绕选择联合

  $stmt = $db->query("(SELECT * 
              FROM posts 
              where status='public' and user='public' 
              order by inde asc limit 12 offset " . $offset . 
          ")  union  ( select * 
          from parchive where status='public' order by date desc limit " . $diff .")");

通过这种方式，UNION可以处理结果集，而不是直接选择

UNION和ORDER BY的使用不正确

1 个答案: