Query that Returns Result Row Numbers, Starting with 1 and Incrementing by 3 : Identity « Sequence Indentity « SQL Server / T-SQL Tutorial

1. SQL Server / T-SQL Tutorial
2. Sequence Indentity
3. Identity

4>
5> CREATE TABLE MyTable (
6>  key_col int NOT NULL IDENTITY (1,1),
7>  abc     char(1) NOT NULL
8> )
9> INSERT INTO MyTable VALUES ('a')
10> INSERT INTO MyTable VALUES ('b')
11> INSERT INTO MyTable VALUES ('c')
12> SELECT * FROM MyTable ORDER BY key_col
13> GO

(1 rows affected)

(1 rows affected)

(1 rows affected)
key_col     abc
----------- ---
          1 a
          2 b
          3 c

(3 rows affected)
1>
2> SELECT
3>  1 +
4>  3 *
5>  (SELECT
6>    count(*)
7>   FROM
8>    MyTable AS T2
9>   WHERE
10>    T2.abc < T1.abc) AS rownum,
11>  abc
12> FROM
13>  MyTable AS T1
14> ORDER BY
15>  abc
16>
17> drop table MyTable
18> GO
rownum      abc
----------- ---
          1 a
          4 b
          7 c

(3 rows affected)
1>