Direttorju tal-Artikoli
MySQLIssortjar kondizzjonali b'ħafna oqsma?MySQL ordni billi dixxendenti u axxendenti dikjarazzjoni/funzjoni tal-mistoqsija
sort MySQL
Nafu li nużaw id-dikjarazzjoni SQL SELECT biex naqraw data mit-tabella MySQL.
Jekk għandna bżonn issortja d-dejta tal-qari, nistgħu nużaw MySQL's ORDNI MILL klawsola biex tissettja liema qasam trid issortja b'liema mod, u mbagħad jirritorna r-riżultati tat-tfittxija.
grammatika
Din li ġejja hija dikjarazzjoni SQL SELECT li tuża l-klawżola ORDER BY biex issolvi d-dejta tal-mistoqsija qabel ma tirritorna d-dejta:
SELECT field1, field2,...fieldN table_name1, table_name2... ORDER BY field1, [field2...] [ASC [DESC]]
- Tista' tuża kwalunkwe qasam bħala kundizzjoni ta' għażla biex tirritorna riżultati ta' mistoqsija magħżula.
- Tista 'tissettja oqsma multipli biex issolvi.
- Tista' tuża l-kliem prinċipali ASC jew DESC biex tissettja r-riżultati tal-mistoqsija biex jiġu magħżula f'ordni axxendenti jew dixxendenti.B'mod awtomatiku, huwa f'ordni axxendenti.
- Tista' żżid klawżoli WHERE...LIKE biex tistabbilixxi kundizzjonijiet.
Bl-użu tal-klawżola ORDER BY fil-prompt tal-kmand
Dan li ġej se juża l-klawżola ORDER BY fid-dikjarazzjoni SQL SELECT biex jaqra d-dejta fit-tabella tad-dejta MySQL chenweiliang_tbl:
eżempju
Ipprova l-eżempji hawn taħt u r-riżultati jiġu magħżula f'ordni axxendenti u dixxendenti.
SQL sort
mysql> use chenweiliang; Database changed mysql> SELECT * from chenweiliang_tbl ORDER BY submission_date ASC; +-----------+---------------+---------------+-----------------+ | chenweiliang_id | chenweiliang_title | chenweiliang_author | submission_date | +-----------+---------------+---------------+-----------------+ | 3 | 学习 Java | chenweiliang.com | 2015-05-01 | | 4 | 学习 Python | chenweiliang.com | 2016-03-06 | | 1 | 学习 PHP | 陈沩亮博客 | 2017-04-12 | | 2 | 学习 MySQL | 陈沩亮博客 | 2017-04-12 | +-----------+---------------+---------------+-----------------+ 4 rows in set (0.01 sec) mysql> SELECT * from chenweiliang_tbl ORDER BY submission_date DESC; +-----------+---------------+---------------+-----------------+ | chenweiliang_id | chenweiliang_title | chenweiliang_author | submission_date | +-----------+---------------+---------------+-----------------+ | 1 | 学习 PHP | 陈沩亮博客 | 2017-04-12 | | 2 | 学习 MySQL | 陈沩亮博客 | 2017-04-12 | | 4 | 学习 Python | chenweiliang.com | 2016-03-06 | | 3 | 学习 Java | chenweiliang.com | 2015-05-01 | +-----------+---------------+---------------+-----------------+ 4 rows in set (0.01 sec)
Aqra d-dejta kollha fit-tabella chenweiliang_tbl u issortja f'ordni axxendenti mill-qasam submission_date.
Bl-użu tal-klawżola ORDER BY fi skript PHP
Tista' tuża l-funzjoni PHP mysqli_query() u l-istess kmand SQL SELECT bi klawżola ORDER BY biex tikseb id-dejta.
Din il-funzjoni tintuża biex tesegwixxi kmandi SQL u mbagħad toħroġ id-dejta kollha mistoqsija permezz tal-funzjoni PHP mysqli_fetch_array().
eżempju
Ipprova l-eżempju li ġej, id-dejta mistoqsija hija rritornata f'ordni dixxendenti tal-qasam submission_date.
MySQL ORDNI B'test:
<?
php
$dbhost = 'localhost:3306'; // mysql服务器主机地址
$dbuser = 'root'; // mysql用户名
$dbpass = '123456'; // mysql用户名密码
$conn = mysqli_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
die('连接失败: ' . mysqli_error($conn));
}
// 设置编码，防止中文乱码
mysqli_query($conn , "set names utf8");
$sql = 'SELECT chenweiliang_id, chenweiliang_title,
chenweiliang_author, submission_date
FROM chenweiliang_tbl
ORDER BY submission_date ASC';
mysqli_select_db( $conn, 'chenweiliang' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
die('无法读取数据: ' . mysqli_error($conn));
}
echo '<h2>陈沩亮博客 MySQL ORDER BY 测试<h2>';
echo '<table border="1"><tr><td>教程 ID</td><td>标题</td><td>作者</td><td>提交日期</td></tr>';
while($row = mysqli_fetch_array($retval, MYSQL_ASSOC))
{
echo "<tr><td> {$row['chenweiliang_id']}</td> ".
"<td>{$row['chenweiliang_title']} </td> ".
"<td>{$row['chenweiliang_author']} </td> ".
"<td>{$row['submission_date']} </td> ".
"</tr>";
}
echo '</table>';
mysqli_close($conn);
?>Hope Chen Weiliang Blog ( https://www.chenweiliang.com/ ) qasmet "MySQL multi-field conditional sorting? MySQL order by dixxendenti u axxendenti query statement/funzjoni", li hija utli għalik.
Merħba biex taqsam il-link ta' dan l-artikolu:https://www.chenweiliang.com/cwl-476.html