2017-07-18 115 views
0

給定一個包含表「TAB1」的數據庫「firstdb」。此表是不是學生信息罷了,可表現爲跟隨從SQL數據庫獲得統計信息HTML

ID Last Name First Name Date of Birth  School    Specialty Sex 
01 yves   marco  03/03/2000  la roccade school  letter  man 
02 marchal  zeko   05-12-1999  johara school   letter  man 
03 ghisil  maria  15-03-2000  johara school   science women 
04 belbali  john   30-10-1999  lever school   science man 
05 santa   sofi   04-05-2000  la roccade school  science women 
06 yves   don   16/04/2000  la roccade school  lette  man 

的perpos如果用這個數據來提取的統計信息,根據一些冒號:「學校,專業,性別」裏的結果應爲如下:

School   Specialty  Sex  number 
la roccade school letter  man   02 
la roccade school letter  women  00 
la roccade school science  man   00 
la roccade school science  women  01 
johara school  letter  man   01 
johara school  letter  women  00 
johara school  science  man   00 
johara school  science  women  01 
lever school  letter  man   00 
lever school  letter  women  00 
lever school  science  man   01 
lever school  science  women  00 

PS:數據量不固定。它可以改變的地方。

回答

1

你只是在尋找一個查詢來獲得想要的結果嗎?這應該工作:

SELECT 
    School, 
    Specialty, 
    Sex, 
    COUNT(ID) AS Number 
FROM TAB1 
GROUP BY 
    School, 
    Specialty, 
    Sex; 
+0

它的工作很好,謝謝。現在的問題是顯示這些數據。含義:僅顯示第二個表中顯示的列:_「學校,專業,性別」_。以及創建一個名爲_「numbers」_的新列來顯示統計信息。非常感謝你。 –