Changing Data and Structure - Mastering phpMyAdmin 3.4 for Effective MySQL Management - page 112

phpMyAdmin handles BIT columns in a binary way. For example, if we edit one
row and set a value of 101 to the some_bits column, the following query is sent at
save time:
UPDATE `marc_book`.`book` SET `some_bits` = b '101'
WHERE `book`.`isbn` = '1-234567-89-0' LIMIT 1;
The highlighted part of this query shows that the column really receives a binary
value. At browse time, the exact value (which in decimal is 5 —a meaningless value
for our purpose) is redisplayed in its binary form 101 , which helps to interpret each
discrete bit value. More details about the notation for bit values are available at
http://dev.mysql.com/doc/refman/5.5/en/bit-type.html .
Managing indexes
Properly maintained indexes are crucial for data retrieval speed. phpMyAdmin has a
number of index management options, which will be covered in this section.
Single-column indexes
We have already seen how the Structure panel offers a quick way to create an index
on a single column, thanks to some links such as Add primary key , Add index ,
and Add unique index . Under the columns list, there is a section of the interface
available to manage indexes:
This section has links to edit or delete every index. Here, the Column part lists only
one column per index, and we can see that the whole column participates in the
index. This is because there is no size information after each column name, contrary
to what will be seen in our next example.