選擇不同和計數在MySQL

Question

不同的是這可能從一個表列中選擇不同的行和在單個查詢

$sql = "SELECT DISTINCT location and COUNT(DISTINCT location) 
     FROM ".$db_name.".$table_name 
     ORDER BY location ASC 
     LIMIT ". $start_page.",". $recordPer_page.""; 

Answer 1

嘗試計數重複的行爲每個不同的領域，

SELECT `location`, COUNT(DISTINCT `location`) 
FROM  .... 
GROUP BY `Location` 
ORDER BY .... 
LIMIT .... 

Answer 2

你好，這查詢幫助你：

SQLFIDDLE example

SELECT `location`, COUNT(`location`) 
    FROM  tbl 
    GROUP BY `location` 
    ORDER BY `location` 

數據：

('Africa'), 
    ('Viena'), 
    ('Mexico'), 
    ('Chicago'), 
    ('Miami'), 
    ('Chicago'), 
    ('Viena'), 
    ('London'), 
    ('Viena'); 

結果：

| LOCATION | COUNT(`LOCATION`) | 
-------------------------------- 
| Africa |     1 | 
| Chicago |     2 | 
| London |     1 | 
| Mexico |     1 | 
| Miami |     1 | 
| Viena |     3 |