SQL Server/T-SQL/Store Procedure Function/Default Parameter

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Paraemter with NULL value

1> create table employee(
2>     ID          int,
3>     name        nvarchar (10),
4>     salary      int,
5>     start_date  datetime,
6>     city        nvarchar (10),
7>     region      char (1))
8> GO
1>
2> insert into employee (ID, name,    salary, start_date, city,       region)
3>               values (1,  "Jason", 40420,  "02/01/94", "New York", "W")
4> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (2,  "Robert",14420,  "01/02/95", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (3,  "Celia", 24020,  "12/03/96", "Toronto",  "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (4,  "Linda", 40620,  "11/04/97", "New York", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (5,  "David", 80026,  "10/05/98", "Vancouver","W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (6,  "James", 70060,  "09/06/99", "Toronto",  "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (7,  "Alison",90620,  "08/07/00", "New York", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (8,  "Chris", 26020,  "07/08/01", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (9,  "Mary",  60020,  "06/09/02", "Toronto",  "W")
3> GO
(1 rows affected)
1>
2> select * from employee
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W
(9 rows affected)
1>
2> drop PROCEDURE GetData
3> GO
1>
2> -- Filtering for Null Values with a Stored Procedure
3>
4> CREATE PROCEDURE GetData
5> @TID int = NULL
6> AS
7> IF @TID IS NOT NULL
8>     SELECT ID, name FROM Employee WHERE ID = @TID
9> ELSE
10>     SELECT id, Name FROM Employee WHERE ID IS NULL
11> GO
1>
2>
3> EXEC GetData 1
4> GO
ID          name
----------- ----------
          1 Jason
(1 rows affected)
1> EXEC GetData NULL
2> GO
id          Name
----------- ----------
(0 rows affected)
1> EXEC GetData
2> GO
id          Name
----------- ----------
(0 rows affected)
1>
2> drop table employee
3> GO
1>



Specifying a Default Parameter Value

1> create table employee(
2>     ID          int,
3>     name        nvarchar (10),
4>     salary      int,
5>     start_date  datetime,
6>     city        nvarchar (10),
7>     region      char (1))
8> GO
1>
2> insert into employee (ID, name,    salary, start_date, city,       region)
3>               values (1,  "Jason", 40420,  "02/01/94", "New York", "W")
4> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (2,  "Robert",14420,  "01/02/95", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (3,  "Celia", 24020,  "12/03/96", "Toronto",  "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (4,  "Linda", 40620,  "11/04/97", "New York", "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (5,  "David", 80026,  "10/05/98", "Vancouver","W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (6,  "James", 70060,  "09/06/99", "Toronto",  "N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (7,  "Alison",90620,  "08/07/00", "New York", "W")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (8,  "Chris", 26020,  "07/08/01", "Vancouver","N")
3> GO
(1 rows affected)
1> insert into employee (ID, name,    salary, start_date, city,       region)
2>               values (9,  "Mary",  60020,  "06/09/02", "Toronto",  "W")
3> GO
(1 rows affected)
1>
2> select * from employee
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W
(9 rows affected)
1>
2> drop PROCEDURE GetData
3> GO
1>
2> -- Specifying a Default Parameter Value
3>
4> CREATE PROCEDURE GetData @TID int = 3
5> AS
6> SELECT * from Employee WHERE ID = @TID
7> GO
1>
2> EXEC GetData 1
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
(1 rows affected)
1>
2> EXEC GetData
3> GO
ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
(1 rows affected)
1>
2> drop table employee
3> GO
1>



Using the system date as a default parameter.

 

5>
6>
7>     CREATE TABLE myusers(
8>         UserID        varchar(30)NOT NULL PRIMARY KEY,
9>         FirstName     varchar(30),
10>         LastName      varchar(30),
11>         EmployeeType  char(1) NOT NULL,
12>         DBAccess      varchar(30),
13>         StartDate     datetime,
14>         ExpDate       datetime
15>     )
16>     GO
1>
2>
3>     CREATE PROC pr_deluser (@TD datetime )
4>     AS
5>     DECLARE getuser_curs CURSOR
6>          FOR
7>               SELECT UserID
8>               FROM myusers
9>               WHERE ExpDate <= @TD
10>     DECLARE @HoldID varchar(30)
11>     DECLARE @MyCount int
12>     SELECT @MyCount = 0
13>     OPEN getuser_curs
14>     FETCH NEXT FROM getuser_curs into @HoldID
15>     WHILE @@FETCH_STATUS = 0 BEGIN
16>          EXEC sp_droplogin @HoldID
17>          EXEC pr_copyuser @HoldID
18>          SELECT @MyCount = @MyCount + 1
19>          FETCH NEXT FROM getuser_curs into @HoldID
20>     END
21>     DECLARE @MyDisp varchar(50)
22>     SELECT @MyDisp = "Number of Users Deleted is " + ltrim(str(@MyCount))
23>     PRINT @MyDisp
24>     CLOSE getuser_curs
25>     DEALLOCATE getuser_curs
26>     GO
Cannot add rows to sysdepends for the current object because it depends on the missing object "pr_copyuser". The object will still be created.
1>
2>
3>     DECLARE @myvalue varchar(12)
4>
5>     SELECT @myvalue=CONVERT(varchar(12), getdate())
6>
7>     EXEC pr_deluser @myvalue
8>     GO
Number of Users Deleted is 0
1>
2>     drop PROC pr_deluser;
3>     GO
1>
2>
3>     drop table myusers;
4>     GO