Yadda ake UPDATE tambaya a cikin MySQL database? UPDATE syntax/umurni/bayani

MySQL databaseYadda ake sabunta tambaya? UPDATE syntax/umurni/bayani

MySQL TAMBAYA TAMBAYA

Idan muna buƙatar gyara ko sabunta bayanai a cikin MySQL, zamu iya amfani da umarnin SQL UPDATE don aiki. .

nahawu

Mai zuwa shine babban tsarin SQL don umarnin UPDATE don canza bayanan tebur na MySQL:

UPDATE table_name SET field1=new-value1, field2=new-value2
[WHERE Clause]

• Kuna iya sabunta filaye ɗaya ko fiye a lokaci guda.
• Kuna iya ƙayyade kowane yanayi a cikin jumlar INA.
• Kuna iya sabunta bayanai lokaci guda a cikin tebur guda.

Maganar INA yana da amfani sosai lokacin da kake buƙatar sabunta bayanai a cikin keɓaɓɓen jere a cikin tebur ɗin bayanai.

Sabunta bayanai ta hanyar umarnin umarni

A ƙasa za mu yi amfani da jumlar WHERE a cikin umarnin SQL UPDATE don sabunta ƙayyadaddun bayanai a cikin tebur chenweiliang_tbl:

misali

Misali mai zuwa zai sabunta darajar filin chenweiliang_title wanda chenweiliang_id shine 3 a cikin tebur na bayanai:

mysql> UPDATE chenweiliang_tbl SET chenweiliang_title='学习 C++' WHERE chenweiliang_id=3;
Query OK, 1 rows affected (0.01 sec)
 
mysql> SELECT * from chenweiliang_tbl WHERE chenweiliang_id=3;
+-----------+--------------+---------------+-----------------+
| chenweiliang_id | chenweiliang_title | chenweiliang_author | submission_date |
+-----------+--------------+---------------+-----------------+
| 3 | 学习 C++ | chenweiliang.com | 2016-05-06 |
+-----------+--------------+---------------+-----------------+
1 rows in set (0.01 sec)

Daga sakamakon, an gyara chenweiliang_title wanda chenweiliang_id shine 3.

Sabunta bayanai ta amfani da rubutun PHP

PHP yana amfani da aikin mysqli_query() don aiwatar da maganganun SQL. Kuna iya amfani da ko kar a yi amfani da jumlar WHERE a cikin maganganun SQL UPDATE.

Lura:Kar a yi amfani da jumlar INA don sabunta duk bayanan da ke cikin tebur ɗin bayanai, don haka a kula.

Wannan aikin yana da tasiri iri ɗaya da aiwatar da bayanin SQL a cikin umarni na mysql>.

misali

Misali mai zuwa zai sabunta bayanan filin chenweiliang_title wanda chenweiliang_id shine 3.

<?
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 = 'UPDATE chenweiliang_tbl
 SET chenweiliang_title="学习 Python"
 WHERE chenweiliang_id=3';
 
mysqli_select_db( $conn, 'chenweiliang' );
$retval = mysqli_query( $conn, $sql );
if(! $retval )
{
 die('无法更新数据: ' . mysqli_error($conn));
}
echo '数据更新成功！';
mysqli_close($conn);
?>