SQL Server/T-SQL Tutorial/System Functions/context info

Session Variables

5> CREATE TABLE titles(
6>    title_id       varchar(20),
7>    title          varchar(80)       NOT NULL,
8>    type           char(12)          NOT NULL,
9>    pub_id         char(4)               NULL,
10>    price          money                 NULL,
11>    advance        money                 NULL,
12>    royalty        int                   NULL,
13>    ytd_sales      int                   NULL,
14>    notes          varchar(200)          NULL,
15>    pubdate        datetime          NOT NULL
16> )
17> GO
1>
2> insert titles values ("1", "Secrets",   "popular_comp", "1389", $20.00, $8000.00, 10, 4095,"Note 1","06/12/94")
3> insert titles values ("2", "The",       "business",     "1389", $19.99, $5000.00, 10, 4095,"Note 2","06/12/91")
4> insert titles values ("3", "Emotional", "psychology",   "0736", $7.99,  $4000.00, 10, 3336,"Note 3","06/12/91")
5> insert titles values ("4", "Prolonged", "psychology",   "0736", $19.99, $2000.00, 10, 4072,"Note 4","06/12/91")
6> insert titles values ("5", "With",      "business",     "1389", $11.95, $5000.00, 10, 3876,"Note 5","06/09/91")
7> insert titles values ("6", "Valley",    "mod_cook",     "0877", $19.99, $0.00,    12, 2032,"Note 6","06/09/91")
8> insert titles values ("7", "Any?",      "trad_cook",    "0877", $14.99, $8000.00, 10, 4095,"Note 7","06/12/91")
9> insert titles values ("8", "Fifty",     "trad_cook",    "0877", $11.95, $4000.00, 14, 1509,"Note 8","06/12/91")
10> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
1>
2>
3> DECLARE @cost money
4> SELECT @cost = price FROM titles
5> WHERE title_id = "bu1032"
6> SET context_info @cost
7> GO
Msg 2743, Level 16, State 3, Server J\SQLEXPRESS, Line 6
SET CONTEXT_INFO statement requires varbinary (128) NOT NULL parameter.
1>
2>
3> drop table titles;
4> GO