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Php connection mysql utf8

Содержание
  1. Set character set using MySQLi
  2. 5 Answers 5
  3. mysql_set_charset
  4. Description
  5. Parameters
  6. Return Values
  7. Notes
  8. See Also
  9. User Contributed Notes 8 notes

Set character set using MySQLi

I’m fetching data in Arabic from MySQL tables with MySQLi. So I usually use this in procedural style:

mysql_query("SET NAMES 'utf8'"); mysql_query('SET CHARACTER SET utf8');

Now I am using the OOP style so I am trying to see if there is something I could set rather than the above? I only found this in PHP manual so I did it, but what about setting names to UTF8?

Note that mysqli_set_charset exists in the procedural style too — there are no differences in the actual capabilities or behaviour of the procedural and OOP styles for using MySQLi. Also note that using SET NAMES or SET CHARACTER SET explicitly here would be wrong in either style; always prefer mysqli_set_charset (or its OOP equivalent).

Do not mix mysql_* and mysqli_* interfaces. Simply do not use the deprecated (and removed in PHP 5.7) mysql_* functions.

5 Answers 5

$mysqli->query(«SET NAMES ‘utf8′»);

From the manual:

This is the preferred way to change the charset. Using mysqli::query() to execute SET NAMES .. is not recommended.

$mysqli->set_charset(«utf8»); is just enough, let the mysqli db driver do the thing for you.

The documentation says . Using mysqli::query() to execute SET NAMES .. is not recommended. php.net/manual/de/mysqli.set-charset.php

@sys_debug It looks like you don’t need to do SET NAMES ‘utf8’ , $mysqli->set_charset(«utf8») will be enough.

Don’t use SET NAMES or SET CHARACTER SET explicitly when using MySQLi., and certainly don’t use both like the question asker here originally was. Reasons that this is a bad idea:

  • Calling SET CHARACTER SET utf8 after SET NAMES utf8 actually just undoes some of the work that SET NAMES did.
  • The PHP manual explicitly warns us to use mysqli_set_charset , not SET NAMES :

This is the preferred way to change the charset. Using mysqli_query() to set it (such as SET NAMES utf8) is not recommended. See the MySQL character set concepts section for more information.

This function works like the SET NAMES statement, but also sets the value of mysql->charset , and thus affects the character set used by mysql_real_escape_string()

It’s thus good practice to only use set_charset , not SET NAMES . There’s nothing that SET NAMES does that set_charset doesn’t, and set_charset avoids the risk of mysqli_real_escape_string behaving incorrectly (or even insecurely).

Источник

mysql_set_charset

This extension was deprecated in PHP 5.5.0, and it was removed in PHP 7.0.0. Instead, the MySQLi or PDO_MySQL extension should be used. See also MySQL: choosing an API guide. Alternatives to this function include:

Description

Sets the default character set for the current connection.

Parameters

A valid character set name.

The MySQL connection. If the link identifier is not specified, the last link opened by mysql_connect() is assumed. If no such link is found, it will try to create one as if mysql_connect() had been called with no arguments. If no connection is found or established, an E_WARNING level error is generated.

Return Values

Returns true on success or false on failure.

Notes

Note:

This function requires MySQL 5.0.7 or later.

Note:

This is the preferred way to change the charset. Using mysql_query() to set it (such as SET NAMES utf8 ) is not recommended. See the MySQL character set concepts section for more information.

See Also

User Contributed Notes 8 notes

I needed to access the database from within one particular webhosting service. Pages are UTF-8 encoded and data received by forms should be inserted into database without changing the encoding. The database is also in UTF-8.

Neither SET character set ‘utf8’ or SET names ‘utf8’ worked properly here, so this workaround made sure all variables are set to utf-8.

// . (creating a connection to mysql) .

mysql_query ( «SET character_set_results = ‘utf8’, character_set_client = ‘utf8’, character_set_connection = ‘utf8’, character_set_database = ‘utf8’, character_set_server = ‘utf8′» , $conn );

$re = mysql_query ( ‘SHOW VARIABLES LIKE «%character_set%»;’ )or die( mysql_error ());
while ( $r = mysql_fetch_assoc ( $re )) < var_dump ( $r ); echo "
» ;> exit;

?>

All important variables are now utf-8 and we can safely use INSERTs or SELECTs with mysql_escape_string($var) without any encoding functions.

Here’s an example of how to use this feature :

I wanted to store arabic characters as UTF8 in the database and as suggested in many of the google results, I tried using

mysql_query(«SET NAMES ‘utf8′»);

mysql_query(«SET CHARACTER SET utf8 «);

Using the following, it worked flawlessly

$link = mysql_connect(‘localhost’, ‘user’, ‘password’);
mysql_set_charset(‘utf8’,$link);

Once this is set we need not manually encode the text into utf using utf8_encode() or other functions. The arabic ( or any UTF8 supported ) text can be passed directly to the database and it is automatically converted by PHP.
For eg.
$link = mysql_connect ( ‘localhost’ , ‘user’ , ‘password’ );
mysql_set_charset ( ‘utf8’ , $link );
$db_selected = mysql_select_db ( ’emp_feedback’ , $link );
if (! $db_selected ) < die ( 'Database access error : ' . mysql_error ());>
$query = «INSERT INTO feedback ( EmpName, Message ) VALUES (‘ $_empName ‘,’ $_message ‘)» ;
mysql_query ( $query ) or die( ‘Error, Feedback insert into database failed’ );
?>
Note that here $_empName is stored in English while $_message is in Arabic.

I assume that this is an equivalent in previous versions of php (add some parameter validation and default values though!):
if (!function_exists(‘mysql_set_charset’)) function mysql_set_charset($charset,$dbh)
return mysql_query(«set names $charset»,$dbh);
>
>
?>

Here’s an improved version of Janez R.’s function:
if ( function_exists ( ‘mysql_set_charset’ ) === false ) /**
* Sets the client character set.
*
* Note: This function requires MySQL 5.0.7 or later.
*
* @see http://www.php.net/mysql-set-charset
* @param string $charset A valid character set name
* @param resource $link_identifier The MySQL connection
* @return TRUE on success or FALSE on failure
*/
function mysql_set_charset ( $charset , $link_identifier = null )
if ( $link_identifier == null ) return mysql_query ( ‘SET CHARACTER SET «‘ . $charset . ‘»‘ );
> else return mysql_query ( ‘SET CHARACTER SET «‘ . $charset . ‘»‘ , $link_identifier );
>
>
>
?>

Actually, this function is available in client libraries in MySQL 4.1.13 and newer, too. So the real version requirement is MySQL >= 5.0.7 OR, if you’re using MySQL 4, then >= 4.1.13.

Massage for nabeelmoidu at gmail dot com:

For me works following code:

$mysqli = mysqli_connect( . );
mysqli_query( $mysqli, ‘SET NAMES «utf8» COLLATE «utf8_general_ci»‘ );

mysqli_set_charset( $mysqli, ‘utf8’ );

I need to revoke most of my post below. What I found out afterwards is this:

1. if you do not use mysql_set_char mysql will NOT do any translations and thus store a utf8-character-byte as is. If you then retrieve this byte from the db and output it in a utf8 page it will show just fine BUT if other apps query this byte (expecting to find a latin1 byte) they will go wrong.

2. the ‘bug’ mentioned before only occurs if you use a ucase or lcase function in your statement (like: latin1_col = ucase(‘utf8 string’)

I just hope that the text below will help someone who is struggling with charset encoding, specially when php-charset is different from the mysql-charset. Let me add that I really think that the php man-pages on the mysql-functions are lacking a lot of details on this important issues. Could someone add some useful text here?

Here is my situation. PHP5.2.4, MySql 4.1.15. A php web-application fully utf-8 encoded and a mysql database in latin1 charset.

To make this work I had to:

1. create and store all code files (php, html, inc, js, etc) in the utf-8 charset. Your editor should have an option for this, if not dump it.

2. check that your editor does not add a BOM (http://en.wikipedia.org/wiki/Byte-order_mark) at the beginning of the file. Use a hex-editor to detect them if needed.

3. Set your apache environment to utf-8 by adding ‘AddDefaultCharset utf-8’ to your .htaccess. If you do not use apache add ‘default_charset utf-8’ to your php.ini. You have to do either of them (not both), php will use the apache setting where needed.

4. Additionally add this meta-tag to your html-header: ». This will help silly browsers (Oeps, IE again?) that ignore the utf-response-header send to them.

5. Check that the above line are listened to by check the ‘page info’ of your pages in firefox. It should show 2 (!!) utf-8 entries.

======== all of the above sofar has nothing to do with mysql 😉 ======

6. Do *NOT* (repeat NOT!) set the ‘names’ (set names *) or _ANY_ ‘character set’ (set character set *) (opposed to what they tell you on these pages).

7. Check the previous item by listing the results of the mysql query ‘SHOW session VARIABLES’. All char_sets here should say ‘latin1’, except for the system one which is always ‘utf8’. All collations should say ‘latin1_*’. Furthermore the php function mysql_client_encoding() should also return latin1 (though I don’t understand why; what does this value mean, I would think if php (being the client) is utf8 encoded this would be utf8?)

8 Finally test the above by storing this string in your db and output it in your webpage: ‘Iñtërnâtiônàlizætiøn and €’.

Now what was interesting during testing and debugging of the above findings was:
1. If I would run ‘mysql_set_charset(‘utf8′)’ _OR_ ‘mysql_query(«SET NAMES ‘utf8′»);’ and then run a query in which I would have ‘where char_column = ‘abc»it would die with ‘Illegal mix of collations’

2. If I would run ‘mysql_query(«SET character_set_client = ‘utf8’;»); mysql_query(«SET character_set_result = ‘utf8′;»)’ the query would work BUT the non-ascii-characters would show scrambled in the browser.

3. BUT these 2 points above work just fine on my local dev-machine (php 5.2.3 & mysql 5.0.45).

This draws me to these 3 conclusions:

1. The Php-mysql-function library (5.2.+) does a fine job translating utf-8 queries & results to/from latin1! It’s better to let php handle this for you then to have mysql do this.

2. Mysql (4.0.+) has 1 or more bugs (well, let’s say unfinished features) that involve the charset-translations that are solved in 5.0.+.

3. It is not well enough documented! (Otherwise I would have to write this)

One last remark: clearly characters that exist in utf8 and not in latin1 (and vv.) will get lost during utf8-latin1-utf8 translation.

If any of the above is not correct or not complete feel free to correct this! (Or better yet, add a chapter to the php manual 🙂

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