SQL Server/T-SQL/Data Type/decimal
Содержание
Average of decimal values
6> CREATE TABLE T (
7> int1 int,
8> bit1 bit,
9> varchar1 varchar(3),
10> dec1 dec(5,2),
11> cmp1 AS (int1 + bit1)
12> )
13> GO
1>
2> INSERT T (int1, bit1) VALUES (1, 0)
3> INSERT T (int1, varchar1) VALUES (2, "abc")
4> INSERT T (int1, dec1) VALUES (3, 5.25)
5> INSERT T (bit1, dec1) VALUES (1, 9.75)
6> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
(1 rows affected)
1> SELECT CAST(AVG(dec1) AS dec(5,2)) "Avg of dec1"
2> FROM T
3> WHERE dec1 IS NOT NULL
4> GO
Avg of dec1
-----------
7.50
(1 rows affected)
1> drop table t;
2> GO
1>
2>
Cast decimal to varchar and append another string
3> CREATE TABLE employee(
4> id INTEGER NOT NULL PRIMARY KEY,
5> first_name VARCHAR(10),
6> last_name VARCHAR(10),
7> salary DECIMAL(10,2),
8> start_Date DATETIME,
9> region VARCHAR(10),
10> city VARCHAR(20),
11> managerid INTEGER
12> );
13> GO
1> INSERT INTO employee VALUES (1, "Jason" , "Martin", 5890,"2005-03-22","North","Vancouver",3);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (2, "Alison", "Mathews",4789,"2003-07-21","South","Utown",4);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (3, "James" , "Smith", 6678,"2001-12-01","North","Paris",5);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (4, "Celia" , "Rice", 5567,"2006-03-03","South","London",6);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (5, "Robert", "Black", 4467,"2004-07-02","East","Newton",7);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (6, "Linda" , "Green" , 6456,"2002-05-19","East","Calgary",8);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (7, "David" , "Larry", 5345,"2008-03-18","West","New York",9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (8, "James" , "Cat", 4234,"2007-07-17","West","Regina",9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (9, "Joan" , "Act", 6123,"2001-04-16","North","Toronto",10);
2> GO
(1 rows affected)
1>
2> select * from employee;
3> GO
id first_name last_name salary start_Date region city managerid
----------- ---------- ---------- ------------ ----------------------- ---------- -------------------- -----------
1 Jason Martin 5890.00 2005-03-22 00:00:00.000 North Vancouver 3
2 Alison Mathews 4789.00 2003-07-21 00:00:00.000 South Utown 4
3 James Smith 6678.00 2001-12-01 00:00:00.000 North Paris 5
4 Celia Rice 5567.00 2006-03-03 00:00:00.000 South London 6
5 Robert Black 4467.00 2004-07-02 00:00:00.000 East Newton 7
6 Linda Green 6456.00 2002-05-19 00:00:00.000 East Calgary 8
7 David Larry 5345.00 2008-03-18 00:00:00.000 West New York 9
8 James Cat 4234.00 2007-07-17 00:00:00.000 West Regina 9
9 Joan Act 6123.00 2001-04-16 00:00:00.000 North Toronto 10
(9 rows affected)
1>
2>
3> SELECT ID, CAST(Salary AS varchar(10)) + " Salary"
4> FROM Employee
5> GO
ID
----------- -----------------
1 5890.00 Salary
2 4789.00 Salary
3 6678.00 Salary
4 5567.00 Salary
5 4467.00 Salary
6 6456.00 Salary
7 5345.00 Salary
8 4234.00 Salary
9 6123.00 Salary
(9 rows affected)
1>
2>
3>
4> drop table employee;
5> GO
Cast int to decimal
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> SELECT ID, Name,
3> CAST(Salary AS dec(12,2)) "Salary in decimal"
4> FROM Employee
5> GO
ID Name Salary in decimal
----------- ---------- -----------------
1 Jason 40420.00
2 Robert 14420.00
3 Celia 24020.00
4 Linda 40620.00
5 David 80026.00
6 James 70060.00
7 Alison 90620.00
8 Chris 26020.00
9 Mary 60020.00
(9 rows affected)
1>
2>
3>
4> drop table employee
5> GO
1>
Cast real number to decimal
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> SELECT city, CAST(SUM(Salary) AS dec(12,2)) "Total"
3> FROM Employee
4> GROUP BY City
5> GO
city Total
---------- --------------
New York 171660.00
Toronto 154100.00
Vancouver 120466.00
(3 rows affected)
1>
2>
3> drop table employee
4> GO
1>
decimal(15,4)
15>
16> SET NOCOUNT ON
17> DECLARE @float1 float, @float2 float, @float3 float, @float4 float
18> DECLARE @dec1 decimal(15,4), @dec2 decimal(15,4),
19> @dec3 decimal(15,4), @dec4 decimal(15,4)
20> DECLARE @pointseven decimal(15,4)
21> SET @float1 = 7
22> SET @float2 = 100
23> SET @float3 = .0009
24> SET @float4 = @float1/@float2 - @float3
25> SET @dec1 = 7
26> SET @dec2 = 100
27> SET @dec3 = .0009
28> SET @dec4 = @dec1/@dec2 - @dec3
29> SET @pointseven = .7
30> SELECT @float4 "@float4", @float3 "@float3",
31> @pointseven - @float4 "float diff"
32> SELECT @dec4 "@dec4", @dec3 "@dec3",
33> @pointseven - @dec4 "dec diff"
34>
35> GO
@float4 @float3 float diff
------------------------ ------------------------ ------------------------
6.9100000000000009E-2 8.9999999999999998E-4 0.63089999999999991
@dec4 @dec3 dec diff
----------------- ----------------- ------------------
.0691 .0009 .6309
1>
Function returning decimal
28>
29> CREATE TABLE project (project_no CHAR(4) NOT NULL,
30> project_name CHAR(15) NOT NULL,
31> budget FLOAT NULL)
32>
33> insert into project values ("p1", "Search Engine", 120000.00)
34> insert into project values ("p2", "Programming", 95000.00)
35> insert into project values ("p3", "SQL", 186500.00)
36>
37> select * from project
38> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
project_no project_name budget
---------- --------------- ------------------------
p1 Search Engine 120000
p2 Programming 95000
p3 SQL 186500
(3 rows affected)
1> -- This function computes additional total costs that arise
2> -- if budgets of projects increase
3>
4> CREATE FUNCTION compute_costs (@percent INT = 10)
5> RETURNS DECIMAL(16,2)
6> BEGIN
7> DECLARE @additional_costs DEC (14,2), @sum_budget dec(16,2)
8> SELECT @sum_budget = SUM (budget) FROM project
9> SET @additional_costs = @sum_budget * @percent/100
10> RETURN @additional_costs
11> END
12> GO
1>
2> SELECT project_no, project_name FROM project WHERE budget < dbo.rupute_costs(25)
3> GO
project_no project_name
---------- ---------------
p2 Programming
(1 rows affected)
1>
2> drop function compute_costs
3> drop table project
4> GO
1>
2>
Use select to do the calculation
12> SET NOCOUNT ON
13> DECLARE @dec1 decimal(38,0)
14> SET @dec1 = CAST(POWER(10,9) as decimal(38,0))
15> SELECT @dec1 * @dec1 * @dec1 * @dec1 * 10 AS "Large Decimal value",
16> FLOOR(LOG10(@dec1 * @dec1 * @dec1 * @dec1 * 10)
17> + 1) AS "Number of digits"
18> GO
Large Decimal value Number of digits
---------------------------------------- ------------------------
10000000000000000000000000000000000000 38
1>
2>