People who prefer to use the keyboard can use the Tab key to go to the next field. Normally, the cursor goes from left to right and from top to bottom, so it would travel into the fields in the Function column (more on this in a moment). However, to ease data navigation in phpMyAdmin, the normal order of navigation has been altered. The Tab key first goes through each field in the Value column, and then through each one in the Function column.

Another way of moving between fields is with the Ctrl + arrow keys. This method might be easier than using the Tab key when many fields are on screen. For this to work, the $cfg['CtrlArrowsMoving'] parameter must be set to true, which is the default value.

If the table's structure permits a NULL value inside a column, a small checkbox appears in the column's Null column. Selecting this puts a NULL value in the column. Whenever data is typed into this column's Value, the Null checkbox is cleared automatically. (This is possible in JavaScript-enabled browsers.)

In the following screenshot, we have modified the structure of the phone column in the author table, to permit a NULL value (refer to the Editing column attribute section in this chapter). The Null checkbox is not selected here:

The corresponding data is erased after selecting the Null box.

MySQL language offers some functions that we may apply to data before saving. Some of these functions appear in a drop-down menu beside each column, if $cfg['ShowFunctionFields'] is set to TRUE.

The function list is defined in the $cfg['Functions'] array. As usual, the default values for these arrays are located in libraries/config.default.php. We may change them by copying the needed section into config.inc.php. If we do so, as these values can change from version to version, we should take care of merging our changes with the values of the new version. The most commonly used functions for a certain data type are displayed first in the list. Some restrictions are defined in the $cfg['RestrictColumnTypes'] and $cfg['RestrictFunctions'] arrays.

As depicted in the following screenshot, we could apply the UPPER function to the title column when saving this row, which would convert the title to uppercase characters:

To gain some screen space, this feature may be disabled by setting $cfg['ShowFunctionFields'] to FALSE. Moreover, the Function column header is clickable, so we can disable this feature on the fly.

When the feature is disabled—either by clicking or via the configuration parameter—a Show : Function link appears in order to display this Function column with a single click as shown in the following screenshot:

A similar feature is available for the Type column header, either by clicking on it or by configuring $cfg['ShowFieldTypesInDataEditView'].

During the course of data maintenance (for permanent duplication or for test purposes), we often have to generate a copy of a row. If this is done in the same table, we must respect the rules of key uniqueness.

Here is an example of row duplication. Our author has written volume 2 of his book about cinema. Hence, the columns that need a slight change are the ISBN, title, and page count. We bring the existing row on screen, change these three columns, and choose Insert as new row, as shown in the following screenshot:

When we click on Go, another row is created with the modified information, leaving the original row unchanged, shown as follows:

A shortcut link exists to achieve the same operation. When browsing the table, clicking on Copy for a specific row brings the edit panel for this row and selects Insert as new row instead of Save.

We can use the red Delete icon beside each row to delete the row. If the value of $cfg['Confirm'] is set to TRUE, every MySQL DELETE statement has to be confirmed before execution. This is the default, as it might not be prudent to allow a row to be deleted with just one click!

The form of the confirmation varies depending on the browser's ability to execute JavaScript. A JavaScript-based confirmation pop up would resemble the following screenshot:

If JavaScript has been disabled in our browser, a distinct panel appears.

The actual DELETE statement will use whatever information is needed to ensure the deletion of only the intended row. In our case, a primary key had been defined and was used in the WHERE clause. In the absence of a primary key, a longer WHERE clause will be generated based on the value of each column. The generated WHERE clause might even prevent the correct execution of the DELETE operation, especially if there are TEXT or BLOB column types. This is because the HTTP transaction, used to send the query to the web server, may be limited in length by the browser or the server. This is another reason why defining a primary key is strongly recommended.

Let us say we examine a page of rows and decide that some rows have to be destroyed. Instead of deleting them one-by-one with the Delete link or icon and as sometimes the decision to delete must be made while examining a group of rows, there are checkboxes beside rows in Table view mode as shown in the following screenshot:

These are used with the Delete icon in the With selected menu. A confirmation screen appears listing all the rows that are about to be deleted.

To completely erase all the rows in a table (leaving its structure intact), we first display the database Structure page by selecting the related database from the navigation panel. We then use the Empty icon or link located on the same line as the table we want to empty, shown as follows:

We get a message confirming the TRUNCATE statement (the MySQL statement used to quickly empty a table). For our exercise, we won't delete this precious data!

A checkbox is present on the left of each table name. We can choose some tables. Then, in the With selected menu, choose the Empty operation as shown in the following screenshot:

Of course, this decision must not be taken lightly!