Formatted sequence - sql

Question

I need to make a SQL Server sequence formatted like this VT-000/2015,
where the zero's is the bill number which increments every record, starting from one in same year which is 2015
e.g:
VT-001/2014,
VT-002/2014,
VT-003/2014,
VT-004/2014,
VT-001/2015,
VT-002/2015
How can I make this?

Answer 1

Materializing the row number in the table is problematic. I think a view is the right tool for this job.
Here is one way to do this by creating a view and using ROW_NUMBER():
CREATE TABLE PRODUCT (PRODUCT_ID int,YEAR INT);
CREATE VIEW dbo.VIEW_PRODUCT AS
SELECT
PRODUCT_ID,
[YEAR],
ROW_NUMBER() OVER(PARTITION BY [YEAR] ORDER by [YEAR]) AS RowNum,
'VT-' + RIGHT(replicate('0', 3)
+ cast(ROW_NUMBER() OVER(PARTITION BY [YEAR] ORDER by [YEAR]) AS VARCHAR(10)), 3)
+ '/' + cast(YEAR AS VARCHAR(4)) as SERIAL
FROM PRODUCT;
INSERT INTO PRODUCT VALUES
(1000,2014),
(2000,2014),
(3000,2015),
(4000,2015),
(5000,2015);
SQL Fiddle Demo

Answer 2

If you're on SQL Server 2012, you can use sequences and a computed column - like this:
Step 1: define your sequence
CREATE SEQUENCE dbo.YearlyNumbers
START WITH 1
INCREMENT BY 1 ;
GO
You can reset that sequence back to 1 every January 1 of a new year, to get new numbers starting at 1, for the new year
Step 2: define your table, include a computed column that concatenates together the various bits and pieces:
CREATE TABLE dbo.Product
(
ProductID INT IDENTITY(1,1) PRIMARY KEY CLUSTERED,
ProductDate DATE,
-- default constraint gets a new value from the sequence on every insert
SequenceValue INT
CONSTRAINT DF_Product_SeqValue DEFAULT(NEXT VALUE FOR YearlyNumbers),
-- computed column puts together all bits to create the formatted ID you're looking for
FormattedID AS 'VT-' + RIGHT('0000' + CAST(SequenceValue AS VARCHAR(4)), 4) +
'/' + CAST(YEAR(ProductDate) AS VARCHAR(4)) PERSISTED
)
Now, when you insert values into your table:
INSERT INTO dbo.Product (ProductDate)
VALUES ('20150115'), ('20150331'), ('20150222'), ('20150414'), ('20150526')
the INSERT will fetch values from the sequence, and the computed column shows the formatted ID as requested:
SELECT * FROM dbo.Product

Answer 3

Consider your table is like this:
CREATE TABLE PRODUCT ([SERIAL] NVARCHAR(30), [YEAR] INT, [COUNTER] INT)
Here is the procedure you can use:
CREATE PROCEDURE PRODUCT_INSERT
#YEAR INT
AS
BEGIN
DECLARE #COUNTER INT
SELECT #COUNTER = ISNULL(MAX([COUNTER]), 0) + 1 FROM PRODUCT
WHERE [YEAR] = #YEAR
INSERT INTO PRODUCT
VALUES ('VT-' + REPLACE(STR(#COUNTER, 3), SPACE(1), '0') + '/' + CONVERT(nvarchar(4),#YEAR), #YEAR, #COUNTER)
END