Learning Mysql

Gamma-quality interface and limited support
The Berkeley DB engine never became a fully integrated and supported part of
MySQL, and it could not be used on some non-Intel architectures. As mentioned earlier, inbuilt support for the BDB engine was officially dropped from MySQL
version 5.1.12.
It’s disk-hungry, like InnoDB
With the features that make it transaction safe and robust to recover comes the cost of extra disk space for storing the information that’s needed. MyISAM is much more compact because it doesn’t have those features.
It’s difficult to setup iYou generally need a compiler to generate the required program files from source code. There are plenty of startup parameters and options, and you need to understand and tune these to make effective use of the BDB engine. This is a good enough reason not to use it, unless you really know what you’re doing and why you want it.
Exercises
Selected exercises in this section concern the music database. You’ll find that the description of table structures in The Music Database in Chapter 4 is a useful reference. Write a join query that displays the name of each artist and the albums they’ve made. Alongside the album, display the number of tracks on the album. Repeat Question 1, but now display only those albums that have more than tracks. Repeat Question 1, but write it as a nested query. What are the four types of nested queries For each typewrite a sample query on the music database. Try to use different keywords in each query, selecting from
ANY
,
ALL
,
EXISTS
(or NOT EXISTS, and
IN
(or NOT IN. What is the difference between an INNER JOIN, a LEFT JOIN, and a RIGHT JOIN Does the order of tables matter in an INNER JOIN
?
Exercises | 275

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