Home Backend Development PHP Problem How to solve the problem of garbled characters in php database query

How to solve the problem of garbled characters in php database query

Jul 24, 2020 am 09:57 AM
php database

Solution to garbled php database query: First create the database in MySQL Command Line Client; then specify the character set of the database so that mysql can support multiple encoding databases at the same time; finally operate the created database. .

How to solve the problem of garbled characters in php database query

Solution to garbled characters

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To solve the garbled code problem, you must first figure out what encoding your database uses. If not specified, the default is latin1.

The three character sets we use most should be gb2312, gbk, and utf8.

So how do we specify the character set of the database? The following is also an example of gbk

[Create a database in MySQL Command Line Client]

mysql> CREATE TABLE `mysqlcode` (
    -> `id` TINYINT( 255 ) UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY ,
    -> `content` VARCHAR( 255 ) NOT NULL
    -> ) TYPE = MYISAM CHARACTER SET gbk COLLATE gbk_chinese_ci;
Query OK, 0 rows affected, 1 warning (0.03 sec)
mysql> desc mysqlcode;
+---------+-----------------------+------+-----+---------+----------------+
| Field   | Type                  | Null | Key | Default | Extra          |
+---------+-----------------------+------+-----+---------+----------------+
| id      | tinyint(255) unsigned | NO   | PRI |         | auto_increment |
| content | varchar(255)          | NO   |     |         |                |
+---------+-----------------------+------+-----+---------+----------------+
2 rows in set (0.02 sec)
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The following TYPE = MYISAM CHARACTER SET gbk COLLATE gbk_chinese_ci;

is the character of the specified database Set, COLLATE (collation), let mysql support multiple encoding databases at the same time.

Of course we can also modify the character set of the database through the following instructions

alter database da_name default character set 'charset'.
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The client sends it in gbk format, and the following configuration can be used:

SET character_set_client='gbk'
SET character_set_connection='gbk'
SET character_set_results='gbk'
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This configuration is equivalent In SET NAMES 'gbk'.

Now operate the database just created

mysql> use test;
Database changed
mysql> insert into mysqlcode values(null,'php爱好者');
ERROR 1406 (22001): Data too long for column 'content' at row 1
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The character set is not specified as gbk, and an error occurred during insertion

mysql> set names 'gbk';
Query OK, 0 rows affected (0.02 sec)
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The specified character set is gbk

mysql> insert into mysqlcode values(null,'php爱好者');
Query OK, 1 row affected (0.00 sec)
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Insert Success

mysql> select * from mysqlcode;
+----+-----------+
| id | content   |
+----+-----------+
| 1  | php爱好着 |
+----+-----------+
1 row in set (0.00 sec)
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When reading without specifying the character set gbk, garbled characters will also appear, as follows

mysql> select * from mysqlcode;
+----+---------+
| id | content |
+----+---------+
| 1  | php???  |
+----+---------+
1 row in set (0.00 sec)
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[Create a database in phpmyadmin and specify the character set]

The table type is based on You need to choose, here choose MyISAM (supports full-text search);

Organize and select gbk_chinese_ci, which is the gbk character set

gbk_bin Simplified Chinese, binary. gbk_chinese_ci Simplified Chinese, case-insensitive.

Insert the database into the database you just created

When you browse again, you find that the code is garbled

Why? It is because the database is gbk character set, and we did not specify it as gbk during operation

Go back to the database homepage

You can see the default latin1_bin for mysql connection proofreading. We change it to gbk_chinese_ci

and insert a piece of data. Look, this is normal

[Solution to php reading database garbled code]

Still taking the database mysqlcode as an example

<?php 
$conn = mysql_connect("localhost","root","89973645"); 
mysql_query("set names &#39;gbk&#39;");//这就是指定数据库字符集,一般放在连接数据库后面就系了 
mysql_select_db("test"); 
 
$sql = "select * from mysqlcode"; 
$result = mysql_query($sql,$conn); 
 
?> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<title>mysql 字符编码</title> 
</head> 
 
<body> 
<table width="300" height="32" border="1" align="center" cellpadding="0" cellspacing="0"> 
 <tr> 
    <td width="71" align="center">id</td> 
    <td width="229" align="center">内容</td> 
 </tr> 
 <?php while($row = mysql_fetch_assoc($result)){ 
 echo "   
 <tr> 
    <td align=/"center/">".$row[&#39;id&#39;]."</td> 
    <td>".$row[&#39;content&#39;]."</td> 
 </tr>"; 
}?>   
</table> 
</body> 
</html> 
<?php mysql_free_result($result);?>
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If we use mysql_query("set names 'gbk '"); Comment it out, it will be garbled when it is sure

Add that sentence and it will be normal again

One sentence

What encoding does your database use? Set it before operating on the database names 'your encoding';

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