you create int auto increment and when you retrive values from that table, use replicate function to fill the zero, or create view

example

CREATE TABLE TESTTABLE
(ID INT PRIMARY KEY IDENTITY(1,1),
 NAME VARCHAR(100))
 
 INSERT INTO TESTTABLE VALUES ('MASTAN')
 INSERT INTO TESTTABLE VALUES ('OLI')
 
 SELECT REPLICATE('0',4-LEN(ID))+CONVERT(VARCHAR,ID) FROM TESTTABLE
 
 CREATE VIEW VIEWTESTTABLE
 AS
 	 SELECT
		REPLICATE('0',4-LEN(ID))+ CONVERT(VARCHAR,ID) [ID],
		NAME
	 FROM
		TESTTABLE
 
 SELECT * FROM VIEWTESTTABLE
 SELECT * FROM VIEWTESTTABLE WHERE NAME LIKE 'OLI'