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mysqli::$error — Возвращает строку с описанием последней ошибки

mysqli_error

mysqli::$error — mysqli_error — Возвращает строку с описанием последней ошибки

Описание

Возвращает сообщение об ошибке последнего вызова функции MySQLi, который может успешно выполниться или провалиться.

Список параметров

Только для процедурного стиля: Идентификатор соединения, полученный с помощью mysqli_connect() или mysqli_init()

Возвращаемые значения

Строка с описанием ошибки. Пустая строка, если ошибки нет.

Примеры

Пример #1 Пример с $mysqli->error

= new mysqli ( «localhost» , «my_user» , «my_password» , «world» );

/* check connection */
if ( $mysqli -> connect_errno ) <
printf ( «Connect failed: %sn» , $mysqli -> connect_error );
exit();
>

if (! $mysqli -> query ( «SET a=1» )) <
printf ( «Errormessage: %sn» , $mysqli -> error );
>

/* close connection */
$mysqli -> close ();
?>

= mysqli_connect ( «localhost» , «my_user» , «my_password» , «world» );

/* check connection */
if ( mysqli_connect_errno ()) <
printf ( «Connect failed: %sn» , mysqli_connect_error ());
exit();
>

if (! mysqli_query ( $link , «SET a=1» )) <
printf ( «Errormessage: %sn» , mysqli_error ( $link ));
>

/* close connection */
mysqli_close ( $link );
?>

Результат выполнения данных примеров:

Смотрите также

• mysqli_connect_errno() — Возвращает код ошибки последней попытки соединения
• mysqli_connect_error() — Возвращает описание последней ошибки подключения
• mysqli_errno() — Возвращает код ошибки последнего вызова функции
• mysqli_sqlstate() — Возвращает код состояния SQLSTATE последней MySQL операции

Источник

mysqli::$error

(PHP 5, PHP 7, PHP

mysqli::$error — mysqli_error — Возвращает строку с описанием последней ошибки

Описание

Возвращает сообщение об ошибке последнего вызова функции MySQLi, который может успешно выполниться или провалиться.

Список параметров

Только для процедурного стиля: объект mysqli , полученный с помощью mysqli_connect() или mysqli_init() .

Возвращаемые значения

Строка с описанием ошибки. Пустая строка, если ошибки нет.

Примеры

Пример #1 Пример с $mysqli->error

= new mysqli ( «localhost» , «my_user» , «my_password» , «world» );

/* Проверить соединение */
if ( $mysqli -> connect_errno ) <
printf ( «Соединение не удалось: %sn» , $mysqli -> connect_error );
exit();
>

if (! $mysqli -> query ( «SET a=1» )) <
printf ( «Сообщение ошибки: %sn» , $mysqli -> error );
>

/* Закрыть соединение */
$mysqli -> close ();
?>

= mysqli_connect ( «localhost» , «my_user» , «my_password» , «world» );

/* Проверить соединение */
if ( mysqli_connect_errno ()) <
printf ( «Соединение не удалось: %sn» , mysqli_connect_error ());
exit();
>

if (! mysqli_query ( $link , «SET a=1» )) <
printf ( «Сообщение ошибки: %sn» , mysqli_error ( $link ));
>

/* Закрыть соединение */
mysqli_close ( $link );
?>

Результат выполнения данных примеров:

Смотрите также

• mysqli_connect_errno() — Возвращает код ошибки последней попытки соединения
• mysqli_connect_error() — Возвращает описание последней ошибки подключения
• mysqli_errno() — Возвращает код ошибки последнего вызова функции
• mysqli_sqlstate() — Возвращает код состояния SQLSTATE последней MySQL операции

User Contributed Notes 7 notes

The mysqli_sql_exception class is not available to PHP 5.05

I used this code to catch errors
= «SELECT XXname FROM customer_table » ;
$res = $mysqli -> query ( $query );

if (! $res ) <
printf ( «Errormessage: %sn» , $mysqli -> error );
>

?>
The problem with this is that valid values for $res are: a mysqli_result object , true or false
This doesn’t tell us that there has been an error with the sql used.
If you pass an update statement, false is a valid result if the update fails.

So, a better way is:
= «SELECT XXname FROM customer_table » ;
$res = $mysqli -> query ( $query );

if (! $mysqli -> error ) <
printf ( «Errormessage: %sn» , $mysqli -> error );
>

?>

This would output something like:
Unexpected PHP error [mysqli::query() [function.query]: (42S22/1054): Unknown column ‘XXname’ in ‘field list’] severity [E_WARNING] in [G:database.php] line [249]

Very frustrating as I wanted to also catch the sql error and print out the stack trace.

A better way is:

( MYSQLI_REPORT_OFF ); //Turn off irritating default messages

$mysqli = new mysqli ( «localhost» , «my_user» , «my_password» , «world» );

$query = «SELECT XXname FROM customer_table » ;
$res = $mysqli -> query ( $query );

if ( $mysqli -> error ) <
try <
throw new Exception ( «MySQL error $mysqli -> error
Query:
$query » , $msqli -> errno );
> catch( Exception $e ) <
echo «Error No: » . $e -> getCode (). » — » . $e -> getMessage () . «
» ;
echo nl2br ( $e -> getTraceAsString ());
>
>

//Do stuff with the result
?>
Prints out something like:
Error No: 1054
Unknown column ‘XXname’ in ‘field list’
Query:
SELECT XXname FROM customer_table

#0 G:\database.php(251): database->dbError(‘Unknown column . ‘, 1054, ‘getQuery()’, ‘SELECT XXname F. ‘)
#1 G:dataWorkSites1framework5testsdbtest.php(29): database->getString(‘SELECT XXname F. ‘)
#2 c:PHPincludessimpletestrunner.php(58): testOfDB->testGetVal()
#3 c:PHPincludessimpletestrunner.php(96): SimpleInvoker->invoke(‘testGetVal’)
#4 c:PHPincludessimpletestrunner.php(125): SimpleInvokerDecorator->invoke(‘testGetVal’)
#5 c:PHPincludessimpletestrunner.php(183): SimpleErrorTrappingInvoker->invoke(‘testGetVal’)
#6 c:PHPincludessimpletestsimple_test.php(90): SimpleRunner->run()
#7 c:PHPincludessimpletestsimple_test.php(498): SimpleTestCase->run(Object(HtmlReporter))
#8 c:PHPincludessimpletestsimple_test.php(500): GroupTest->run(Object(HtmlReporter))
#9 G:all_tests.php(16): GroupTest->run(Object(HtmlReporter))

This will actually print out the error, a stack trace and the offending sql statement. Much more helpful when the sql statement is generated somewhere else in the code.

The decription «mysqli_error — Returns a string description of the LAST error» is not exactly that what you get from mysqli_error. You get the error description from the last mysqli-function, not from the last mysql-error.

If you have the following situation

if (!$mysqli->query(«SET a=1»)) <
$mysqli->query(«ROLLBACK;»)
printf(«Errormessage: %sn», $mysqli->error);
>

you don’t get an error-message, if the ROLLBACK-Query didn’t failed, too. In order to get the right error-message you have to write:

if (!$mysqli->query(«SET a=1»)) <
printf(«Errormessage: %sn», $mysqli->error);
$mysqli->query(«ROLLBACK;»)
>

I had to set mysqli_report(MYSQLI_REPORT_ALL) at the begin of my script to be able to catch mysqli errors within the catch block of my php code.

Initially, I used the below code to throw and subsequent catch mysqli exceptions

try <
$mysqli = new mysqli ( ‘localhost’ , ‘root’ , ‘pwd’ , ‘db’ );
if ( $mysqli -> connect_errno )
throw new Exception ( $mysqli -> connect_error );

> catch ( Exception $e ) <
echo $e -> getMessage ();
>

I realized the exception was being thrown before the actual throw statement and hence the catch block was not being called .

My current code looks like
mysqli_report ( MYSQLI_REPORT_ALL ) ;
try <
$mysqli = new mysqli ( ‘localhost’ , ‘root’ , ‘pwd’ , ‘db’ );
/* I don’t need to throw the exception, it’s being thrown automatically */

> catch ( Exception $e ) <
echo $e -> getMessage ();
>

This works fine and I ‘m able to trap all mysqli errors

// The idea is the add formated errors information for developers to easier bugs detection.

$myfile = fopen ( «database_log.log» , «r» );
$db = new mysqli ( «localhost» , «root» , «root» , «data» );
if(! $db -> query ( «SELECT» )) <
$timestamp = new DateTime ();
$data_err = » <
»title»: » Select statement error »,
»date_time»: » . $timestamp -> getTimestamp (). «,
»error»:» » . $db -> error . » »
> » ; // Do more information
fwrite ( $myfile , $data_err ); // writing data
>
// In separate file do file read and format it for good visual.

$db -> close ();
fclose ( $myfile );
?>

Please note that the string returned may contain data initially provided by the user, possibly making your code vulnerable to XSS.

So even if you escape everything in your SQL query using mysqli_real_escape_string(), make sure that if you plan to display the string returned by mysqli_error() you run that string through htmlspecialchars().

As far as I can tell the two escape functions don’t escape the same characters, which is why you need both (the first for SQL and the second for HTML/JS).

Hi, you can also use the new mysqli_sql_exception to catch sql errors.
Example:
//set up $mysqli_instance here..
$Select = «SELECT xyz FROM mytable » ;
try <
$res = $mysqli_instance -> query ( $Select );
>catch ( mysqli_sql_exception $e ) <
print «Error Code
» . $e -> getCode ();
print «Error Message
» . $e -> getMessage ();
print «Strack Trace
» . nl2br ( $e -> getTraceAsString ());
>

Источник

mysql_error

mysql_error — Returns the text of the error message from previous MySQL operation

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

Returns the error text from the last MySQL function. Errors coming back from the MySQL database backend no longer issue warnings. Instead, use mysql_error() to retrieve the error text. Note that this function only returns the error text from the most recently executed MySQL function (not including mysql_error() and mysql_errno() ), so if you want to use it, make sure you check the value before calling another MySQL function.

Parameters

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 the error text from the last MySQL function, or » (empty string) if no error occurred.

Examples

Example #1 mysql_error() example

= mysql_connect ( «localhost» , «mysql_user» , «mysql_password» );

mysql_select_db ( «nonexistentdb» , $link );
echo mysql_errno ( $link ) . «: » . mysql_error ( $link ). «n» ;

mysql_select_db ( «kossu» , $link );
mysql_query ( «SELECT * FROM nonexistenttable» , $link );
echo mysql_errno ( $link ) . «: » . mysql_error ( $link ) . «n» ;
?>

The above example will output something similar to:

See Also

• mysql_errno() — Returns the numerical value of the error message from previous MySQL operation
• » MySQL error codes

User Contributed Notes 14 notes

If you want to display errors like «Access denied. «, when mysql_error() returns «» and mysql_errno() returns 0, use $php_errormsg. This Warning will be stored there. You need to have track_errors set to true in your php.ini.

Note. There is a bug in either documentation about error_reporting() or in mysql_error() function cause manual for mysql_error(), says: «Errors coming back from the MySQL database backend no longer issue warnings.» Which is not true.

Be aware that if you are using multiple MySQL connections you MUST support the link identifier to the mysql_error() function. Otherwise your error message will be blank.

Just spent a good 30 minutes trying to figure out why i didn’t see my SQL errors.

Using a manipulation of josh ><>‘s function, I created the following. It’s purpose is to use the DB to store errors. It handles both original query, as well as the error log. Included Larry Ullman’s escape_data() as well since I use it in q().

function escape_data ( $data ) <
global $dbc ;
if( ini_get ( ‘magic_quotes_gpc’ )) <
$data = stripslashes ( $data );
>
return mysql_real_escape_string ( trim ( $data ), $dbc );
>

function q ( $page , $query ) <
// $page
$result = mysql_query ( $query );
if ( mysql_errno ()) <
$error = «MySQL error » . mysql_errno (). «: » . mysql_error (). «n
When executing:
n $query n
» ;
$log = mysql_query ( «INSERT INTO db_errors (error_page,error_text) VALUES (‘ $page ‘,’» . escape_data ( $error ). «‘)» );
>
>

// Run the query using q()
$query = «INSERT INTO names (first, last) VALUES (‘myfirst’, ‘mylast’» );
$result = q ( «Sample Page Title» , $query );
?>

When creating large applications it’s quite handy to create a custom function for handling queries. Just include this function in every script. And use db_query(in this example) instead of mysql_query.

This example prompts an error in debugmode (variable $b_debugmode ). An e-mail with the error will be sent to the site operator otherwise.

The script writes a log file in directory ( in this case /log ) as well.

The system is vulnerable when database/query information is prompted to visitors. So be sure to hide this information for visitors anytime.

$system_operator_mail = ‘developer@company.com’ ;
$system_from_mail = ‘info@mywebsite.com’ ;

function db_query ( $query ) <
global $b_debugmode ;

// Perform Query
$result = mysql_query ( $query );

// Check result
// This shows the actual query sent to MySQL, and the error. Useful for debugging.
if (! $result ) <
if( $b_debugmode ) <
$message = ‘Invalid query:
‘ . mysql_error () . ‘

raise_error ( ‘db_query_error: ‘ . $message );
>
return $result ;
>

function raise_error ( $message ) <
global $system_operator_mail , $system_from_mail ;

$serror =
«Env: » . $_SERVER [ ‘SERVER_NAME’ ] . «rn» .
«timestamp: » . Date ( ‘m/d/Y H:i:s’ ) . «rn» .
«script: » . $_SERVER [ ‘PHP_SELF’ ] . «rn» .
«error: » . $message . «rnrn» ;

// open a log file and write error
$fhandle = fopen ( ‘/logs/errors’ . date ( ‘Ymd’ ). ‘.txt’ , ‘a’ );
if( $fhandle ) <
fwrite ( $fhandle , $serror );
fclose (( $fhandle ));
>

// e-mail error to system operator
if(! $b_debugmode )
mail ( $system_operator_mail , ‘error: ‘ . $message , $serror , ‘From: ‘ . $system_from_mail );
>

My suggested implementation of mysql_error():

$result = mysql_query($query) or die(«A fatal MySQL error occured.n
Query: » . $query . «
nError: (» . mysql_errno() . «) » . mysql_error());

This will print out something like.

A fatal MySQL error occured.
Query: SELECT * FROM table
Error: (err_no) Bla bla bla, you did everything wrong

It’s very useful to see your query in order to detect problems with syntax. Most often, the output message from MySQL doesn’t let you see enough of the query in the error message to let you see where your query went bad- it a missing quote, comma, or ( or ) could have occured well before the error was detected. I do -not- recomend using this procedure, however, for queries which execute on your site that are not user-specific as it has the potential to leak sensative data. Recomended use is just for debugging/building a script, and for general user-specific queries which would at the worst, leak the users own information to themself.

When dealing with user input, make sure that you use
echo htmlspecialchars ( mysql_error ());
?>
instead of
echo mysql_error ();
?>

Otherwise it might be possible to crack into your system by submitting data that causes the SQL query to fail and that also contains javascript commands.

Would it make sense to change the examples in the documentation for mysql_query () and for mysql_error () accordingly?

some error can’t handle. Example:

ERROR 1044: Access denied for user: ‘ituser@mail.ramon.intranet’ to database ‘itcom’

This error ocurrs when a intent of a sql insert of no authorized user. The results: mysql_errno = 0 and the mysql_error = «» .

«Errors coming back from the MySQL database backend no longer issue warnings.» Please note, you have an error/bug here. In fact, MySQL 5.1 with PHP 5.2:

Warning: mysql_connect() [function.mysql-connect]: Unknown MySQL server host ‘locallllllhost’ (11001)

That’s a warning, which is not trapped by mysql_error()!

My suggested implementation of mysql_error():

$result = mysql_query($query) or die(«A fatal MySQL error occured.n
Query: » . $query . «
nError: (» . mysql_errno() . «) » . mysql_error());

This will print out something like.

A fatal MySQL error occured.
Query: SELECT * FROM table
Error: (err_no) Bla bla bla, you did everything wrong

It’s very useful to see your query in order to detect problems with syntax. Most often, the output message from MySQL doesn’t let you see enough of the query in the error message to let you see where your query went bad- it a missing quote, comma, or ( or ) could have occured well before the error was detected. I do -not- recomend using this procedure, however, for queries which execute on your site that are not user-specific as it has the potential to leak sensative data. Recomended use is just for debugging/building a script, and for general user-specific queries which would at the worst, leak the users own information to themself.

Oops, the code in my previous post only works for queries that don’t return data (INSERT, UPDATE, DELETE, etc.), this updated function should work for all types of queries (using $result = myquery($query);):

function myquery ($query) <
$result = mysql_query($query);
if (mysql_errno())
echo «MySQL error «.mysql_errno().»: «.mysql_error().»n
When executing:
n$queryn
«;
return $result;
>

This is a big one — As of MySQL 4.1 and above, apparently, the way passwords are hashed has changed. PHP 4.x is not compatible with this change, though PHP 5.0 is. I’m still using the 4.x series for various compatibility reasons, so when I set up MySQL 5.0.x on IIS 6.0 running PHP 4.4.4 I was surpised to get this error from mysql_error():

MYSQL: Client does not support authentication protocol requested by server; consider upgrading MySQL client

According to the MySQL site (http://dev.mysql.com/doc/refman/5.0/en/old-client.html) the best fix for this is to use the OLD_PASSWORD() function for your mysql DB user. You can reset it by issuing to MySQL:

Set PASSWORD for ‘user’@’host’ = OLD_PASSWORD(‘password’);

Источник

Definition and Usage

The mysqli_error() function returns the description of the error occurred during the last MySQLi function call.

Syntax

mysqli_error($con)

Parameters

Return Values

PHP mysqli_error() function returns an string value representing the description of the error from the last MySQLi function call. If there are no errors this function returns an empty string.

PHP Version

This function was first introduced in PHP Version 5 and works works in all the later versions.

Example

Following example demonstrates the usage of the mysqli_error() function (in procedural style) −

<?php
   //Creating a connection
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   //Query to retrieve all the rows of employee table
   mysqli_query($con, "SELECT * FORM employee");

   //Error
   $error = mysqli_error($con);
   print("Error Occurred: ".$error);

   //Closing the connection
   mysqli_close($con);
?>

This will produce following result −

Error Occurred: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FORM employee' at line 1

Example

In object oriented style the syntax of this function is $con ->error. Following is the example of this function in object oriented style −

<?php
   //Creating a connection
   $con = new mysqli("localhost", "root", "password", "mydb");

   //Query to retrieve all the rows of employee table
   $con -> query("SELECT * FROM wrong_table_name");

   //Error 
   $error = $con ->error;
   print("Error Occurred: ".$error);

   //Closing the connection
   $con -> close();
?>

This will produce following result −

Error Occurred: Table 'mydb.wrong_table_name' doesn't exist

Example

Following is another example of the mysqli_error() function −

<?php
   //Creating a connection
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   //Query to SELECT all the rows of the employee table
   mysqli_query($con, "SELECT * FROM employee");
   print("Errors in the SELECT query: ".mysqli_error($con)."n");

   //Query to UPDATE the rows of the employee table
   mysqli_query($con, "UPDATE employee set INCOME=INCOME+5000 where FIRST_NAME in (*)");
   print("Errors in the UPDATE query: ".mysqli_error($con)."n");

   //Query to INSERT a row into the employee table
   mysqli_query($con, "INSERT INTO employee VALUES (Archana, 'Mohonthy', 30, 'M', 13000, 106)");
   print("Errors in the INSERT query: ".mysqli_error($con)."n");
  
   //Closing the connection
   mysqli_close($con);
?>

This will produce following result −

Errors in the SELECT query:
Errors in the UPDATE query: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '*)' at line 1
Errors in the INSERT query: Unknown column 'Archana' in 'field list'

Example

<?php
   $connection_mysql = mysqli_connect("localhost","root","password","mydb");
   
   if (mysqli_connect_errno($connection_mysql)){
      echo "Failed to connect to MySQL: " . mysqli_connect_error();
   }
   
   if (!mysqli_query($connection_mysql,"INSERT INTO employee (FirstName) VALUES ('Jack')")){
      echo("Error description: " . mysqli_error($connection_mysql));
   }
   
   mysqli_close($connection_mysql);
?>

This will produce following result −

Error description: Unknown column 'FirstName' in 'field list'

php_function_reference.htm

PHP: Tips of the Day

PHP — Generating a random password in PHP

Security warning: rand() is not a cryptographically secure pseudorandom number generator. Look elsewhere for generating a cryptographically secure pseudorandom string in PHP.

Try this (use strlen instead of count, because count on a string is always 1):

function randomPassword() {
    $alphabet = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';
    $pass = array(); //remember to declare $pass as an array
    $alphaLength = strlen($alphabet) - 1; //put the length -1 in cache
    for ($i = 0; $i < 8; $i++) {
        $n = rand(0, $alphaLength);
        $pass[] = $alphabet[$n];
    }
    return implode($pass); //turn the array into a string
}

Ref : https://bit.ly/39BNAs0