PHP MySQL Order By ???

ORDER BY ???? ??? ??? ???? ???? ? ?????.

ORDER BY ???

ORDER BY ???? ??? ??? ???? ???? ? ?????.

ORDER BY ???? ????? ???? ?????? ?????.

?????? ????? DESC ???? ?????.

??

SELECT ?? ??

FROM table_name

ORDER BY ?? ?? ASC|DESC

GROUP BY? ???? ??? ????.

GROUP BY? ?? ? ??? COUNT? ?? ????? ????

SELECT city, COUNT(city) FROM cv GROUP BY city;

? ???? ? ??? ??? ?? ??? ? ????. ?? ??? ???? ?? ?? ??? GROUP?? ??? ?????

LIMIT ???? ?? ??? ??:

SELECT col_name FROM tbl_name LIMIT offset,rows;

?offset: ?? ??? ??? ??? ???? ?? ??? ???? ?: ??? ??? ??

? ?? ???(0)?? 5? ??? ????

SELECT * FROM cv LIMIT 5;

SELECT * FROM cv LIMIT 0, 5;

6?? ???(5)?? 5? ??? ????

SELECT * FROM cv LIMIT 5 , 5;

Having? ???? ??? ????.

Having? ???? ??? ?? ????? ?? ???? ??? ? ????. results

SELECT city, COUNT(city) FROM cv GROUP BY city HAVING COUNT(city) >

? ???? ?? ???? ???? ?? ??? ??? ?? ?????? ?????. ?? 2? ???? ?? ??

??? ?? ?????? HAVING? ??? ??? SELECT? ?? ??? ??? ???? ???. , city ??? have? ?? ?? ???? ??? ? ????. ?? ??? ???? ?? ? ? ?? ??? ?? ???? ?????.

?? ??? ???

SELECT name FROM cv WHERE age > 20 GROUP BY city;

? ?? ?? age>20??? ??? ?? ??? ???? ?????. ?? ??? ???

? ? ???? ??? ???? ?, ???? ?? ????? ?? ?? ???? ??? ????? ?? ?

?

?? ???? "Persons" ???? ??? ?? ???? ???? "Age" ?? ???? ??? ?????.

<?php
$con=mysqli_connect("localhost","username","password","database");
// 檢測(cè)連接
if (mysqli_connect_errno())
{
         echo "連接失敗: " . mysqli_connect_error();
}
 
$result = mysqli_query($con,"SELECT * FROM Persons ORDER BY age");
 
while($row = mysqli_fetch_array($result))
{
         echo $row['FirstName'];
         echo " " . $row['LastName'];
         echo " " . $row['Age'];
         echo "<br>";
}
 
mysqli_close($con);
?>

? ??? ??? ?? ?????.

Glenn Quagmire 33

Peter Griffin 35

? ? ?? ??

?? ? ???? ??? ? ????. ?? ?? ???? ???? ?? ? ?? ?? ?? ??? ???? ? ?? ?? ?????.

SELECT ??_??(s) FROM ???_?? ORDER BY ??1, ??2