Littafin Adireshi
Tsarin rarrabawa na MySQL da yawa? ODAR MySQL TA hanyar saukowa/hawa bayanin tambaya/aiki na oda
MySQL irin
Mun san yin amfani da bayanin SQL SELECT don karanta bayanai daga tebur MySQL.
Idan muna buƙatar tsara bayanan da aka karanta, za mu iya amfani da sashin MySQL's ORDER BY don ƙayyade wane fili da hanyar rarrabawa muke son amfani da shi, sannan mu mayar da sakamakon bincike.
nahawu
Mai zuwa shine bayanin SQL SELECT wanda ke amfani da ORDER BY jumla don warware bayanan tambaya kafin mayar da bayanan:
SELECT field1, field2,...fieldN table_name1, table_name2... ORDER BY field1, [field2...] [ASC [DESC]]
- Kuna iya amfani da kowane fanni azaman nau'in yanayin dawo da sakamakon da aka jera.
- Kuna iya saita filaye da yawa don rarrabewa.
- Kuna iya amfani da kalmomin ASC ko DESC don saita sakamakon tambayar da za a jera su a cikin tsari mai hawa ko sauka.Ta hanyar tsoho, yana cikin tsari mai hawa.
- Zaku iya ƙara INA...KAMAR magana don saita yanayi.
Amfani da ORDER BY sashe a cikin umarni da sauri
Mai zuwa zai yi amfani da ORDER BY jumla a cikin bayanin SQL SELECT don karanta bayanai a cikin teburin bayanan MySQL chenweiliang_tbl:
misali
Gwada misalan da ke ƙasa kuma za a jera sakamakon a cikin tsari mai hawa da sauka.
SQL irin
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)
Karanta duk bayanan da ke cikin tebur na chenweiliang_tbl kuma a tsara su cikin tsari mai hawa ta filin submission_date.
Amfani da ORDER BY sashe a cikin rubutun PHP
Kuna iya amfani da aikin PHP mysqli_query() da kuma umarnin SQL SELECT iri ɗaya tare da ORDER BY jumla don samun bayanan.
Ana amfani da wannan aikin don aiwatar da umarnin SQL sannan a fitar da duk bayanan da aka nema ta hanyar aikin PHP mysqli_fetch_array().
misali
Gwada misali mai zuwa, ana dawo da bayanan da aka nema a tsarin saukowa na filin ƙaddamarwa_date.
MySQL ORDER TA gwaji:
<?
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);
?>Da fatan, labarin "MySQL Multi-Field Rarraba Yanayin? MySQL ORDER BY Descending/Ascending Order Query Statement/Action" da aka raba a shafin yanar gizon Chen Weiliang ( https://www.chenweiliang.com/ ) zai taimaka muku.
Ku ji daɗin raba wannan labarin ta hanyar haɗin yanar gizo: https://www.chenweiliang.com/cwl-476.html