Beginning SQL

Chapter 3
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MemberId FirstName
1 Katie
3 Sandra
4 Steve
5 John
6 Jenny
7 John
8 Jack
9 Seymour
The order of the results in the example database table usually reflects on the order in which the records
were first entered into the database, but the order is not guaranteed, so don’t worry if your order looks
different from what appears in the preceding table. Chapter 4 shows you how to create a columns index
on columns to determine the order of results. Later in this chapter, you learn how to use the ORDER BY
clause to specify the order in which records are returned.
Specifying which columns you want returned is fine, but sometimes you may want all of the columns,
which is a lot of typing if your table has many fields. The good news is that SQL provides a shorthand
way of selecting all the columns without having to type out all their names. Instead of typing the column
names, just type an asterisk:
SELECT * FROM Location;
The preceding code fragment is the same as writing the following:
SELECT LocationId, Street, City, State FROM Location;
Both lines of code return the following results:
LocationId Street City State
1 Main Street Orange Town New State
2 Winding Road Windy Village Golden State
3 Tiny Terrace Big City Mega State
However, use shorthand only when you need all the columns, otherwise you make the database system
provide information you don’t need, which wastes CPU power and memory. Memory and CPU power
may not matter on a small database, but they make a huge difference on a large database being accessed
by many people.