Known limitations

3.1 When using HTTP authentication, a user who logged out can not log in again in with the same nick.

这是 phpMyAdmin 的认证机制引起的问题。要解决此问题,请关闭所有已打开的 Windows 文件夹,然后重新登录 phpMyAdmin。

3.2 When dumping a large table in compressed mode, I get a memory limit error or a time limit error.

Compressed dumps are built in memory and because of this are limited to php’s memory limit. For gzip/bzip2 exports this can be overcome since 2.5.4 using $cfg['CompressOnFly'] (enabled by default). zip exports can not be handled this way, so if you need zip files for larger dump, you have to use another way.

3.3 With InnoDB tables, I lose foreign key relationships when I rename a table or a column.

This is an InnoDB bug, see [https://bugs.mysql.com/bug.php?id=21704](https://bugs.mysql.com/bug.php?id=21704)\.

3.4 I am unable to import dumps I created with the mysqldump tool bundled with the MySQL server distribution.

The problem is that older versions of mysqldump created invalid comments like this:

  1. -- MySQL dump 8.22
  2. --
  3. -- Host: localhost Database: database
  4. ---------------------------------------------------------
  5. -- Server version 3.23.54

The invalid part of the code is the horizontal line made of dashes that appears once in every dump created with mysqldump. If you want to run your dump you have to turn it into valid MySQL. This means, you have to add a whitespace after the first two dashes of the line or add a # before it: -- ------------------------------------------------------- or #---------------------------------------------------------

3.5 When using nested folders, multiple hierarchies are displayed in a wrong manner.

Please note that you should not use the separating string multiple times without any characters between them, or at the beginning/end of your table name. If you have to, think about using another TableSeparator or disabling that feature.

参见

$cfg['NavigationTreeTableSeparator']

3.6 (withdrawn).

3.7 I have table with many (100+) columns and when I try to browse table I get series of errors like “Warning: unable to parse url”. How can this be fixed?

Your table neither have a primary key nor an unique key, so we must use a long expression to identify this row. This causes problems to parse_url function. The workaround is to create a primary key or unique key.

3.8 I cannot use (clickable) HTML-forms in columns where I put a MIME-Transformation onto!

Due to a surrounding form-container (for multi-row delete checkboxes), no nested forms can be put inside the table where phpMyAdmin displays the results. You can, however, use any form inside of a table if keep the parent form-container with the target to tbl_row_delete.php and just put your own input-elements inside. If you use a custom submit input field, the form will submit itself to the displaying page again, where you can validate the $HTTP_POST_VARS in a transformation. For a tutorial on how to effectively use transformations, see our Link section on the official phpMyAdmin-homepage.

3.9 I get error messages when using “–sql_mode=ANSI” for the MySQL server.

When MySQL is running in ANSI-compatibility mode, there are some major differences in how SQL is structured (see [https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html](https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html)\). Most important of all, the quote-character (“) is interpreted as an identifier quote character and not as a string quote character, which makes many internal phpMyAdmin operations into invalid SQL statements. There is no workaround to this behaviour. News to this item will be posted in issue #7383.

3.10 Homonyms and no primary key: When the results of a SELECT display more that one column with the same value (for example SELECT lastname from employees where firstname like 'A%' and two “Smith” values are displayed), if I click Edit I cannot be sure that I am editing the intended row.

Please make sure that your table has a primary key, so that phpMyAdmin can use it for the Edit and Delete links.

3.11 The number of rows for InnoDB tables is not correct.

phpMyAdmin uses a quick method to get the row count, and this method only returns an approximate count in the case of InnoDB tables. See $cfg['MaxExactCount'] for a way to modify those results, but this could have a serious impact on performance. However, one can easily replace the approximate row count with exact count by simply clicking on the approximate count. This can also be done for all tables at once by clicking on the rows sum displayed at the bottom.

参见

$cfg['MaxExactCount']

3.12 (withdrawn).

3.13 I get an error when entering USE followed by a db name containing an hyphen.

The tests I have made with MySQL 5.1.49 shows that the API does not accept this syntax for the USE command.

3.14 I am not able to browse a table when I don’t have the right to SELECT one of the columns.

This has been a known limitation of phpMyAdmin since the beginning and it’s not likely to be solved in the future.

3.15 (withdrawn).

3.16 (withdrawn).

3.17 (withdrawn).

3.18 When I import a CSV file that contains multiple tables, they are lumped together into a single table.

There is no reliable way to differentiate tables in CSV format. For the time being, you will have to break apart CSV files containing multiple tables.

3.19 When I import a file and have phpMyAdmin determine the appropriate data structure it only uses int, decimal, and varchar types.

Currently, the import type-detection system can only assign these MySQL types to columns. In future, more will likely be added but for the time being you will have to edit the structure to your liking post-import. Also, you should note the fact that phpMyAdmin will use the size of the largest item in any given column as the column size for the appropriate type. If you know you will be adding larger items to that column then you should manually adjust the column sizes accordingly. This is done for the sake of efficiency.

3.20 After upgrading, some bookmarks are gone or their content cannot be shown.

At some point, the character set used to store bookmark content has changed. It’s better to recreate your bookmark from the newer phpMyAdmin version.

3.21 I am unable to log in with a username containing unicode characters such as á.

This can happen if MySQL server is not configured to use utf-8 as default charset. This is a limitation of how PHP and the MySQL server interact; there is no way for PHP to set the charset before authenticating.

参见

phpMyAdmin issue 12232, MySQL documentation note