The SELECT command
is used to query tables and views for data. You specify what you want via a
SELECT
statement, and the
server "serves" it to you via a result set—a collection of rows
containing the data you
requested. SELECT is
the Swiss Army knife of basic SQL.
It can join tables, retrieve data you
request, assign local
variables, and even create other tables. It's a fair guess that you'll use the
SELECT statement more than any other
single command in Transact-SQL.
We'll begin
exploring SELECT by listing the contents of the tables you just built. Execute
SELECT * FROM tablename
in Query Analyzer,
replacing tablename with the name of each of the three tables. You
should find that the
CUSTOMER and items
tables have three rows each, while orders has four.
SELECT * FROM
customers
(Results abridged)
CustomerNumber
LastName FirstName StreetAddress
--------------
-------- --------- -------------
1 Doe John 123
Joshua Tree
2 Doe Jane 123
Joshua Tree
3 Citizen John 57
Riverside
SELECT * FROM orders
OrderNumber
OrderDate CustomerNumber ItemNumber Amount
-----------
----------------------- -------------- ---------- --------
101 1990-10-18
00:00:00.000 1 1001 123.45
102 1992-02-27
00:00:00.000 2 1002 678.90
103 1995-05-20
00:00:00.000 3 1003 86753.09
104 1997-11-21
00:00:00.000 1 1002 678.90
SELECT * FROM items
ItemNumber
Description Price
---------- -----------
--------
1001 WIDGET A 123.45
1002 WIDGET B 678.90
1003 WIDGET C
86753.09
TSQL Tutorial..
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