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1USE tempdb
2
3DROP TABLE IF EXISTS dbo.SkewedUp
4
5CREATE TABLE dbo.SkewedUp (Id INT NOT NULL, INDEX cx_su CLUSTERED (Id))
6
7INSERT dbo.SkewedUp WITH ( TABLOCK ) ( Id )
8SELECT CASE WHEN x.r % 15 = 0 THEN 1
9            WHEN x.r % 5 = 0 THEN 1000
10            WHEN x.r % 3 = 0 THEN 10000
11            ELSE 100000
12       END AS Id
13FROM   (   SELECT     TOP 1000000 ROW_NUMBER() OVER ( ORDER BY @@DBTS ) AS r
14           FROM       sys.messages AS m
15           CROSS JOIN sys.messages AS m2 ) AS x;
16
17UPDATE STATISTICS dbo.SkewedUp WITH FULLSCAN
18
19SELECT su.Id, COUNT(*) AS records
20FROM dbo.SkewedUp AS su
21GROUP BY su.Id
22
23GO 
24
25CREATE OR ALTER PROC dbo.if_logic
26(
27    @Id INT
28)
29AS
30    BEGIN
31
32        IF @Id = 1
33            BEGIN
34
35                SELECT COUNT(*)
36                FROM   dbo.SkewedUp AS su
37                WHERE  su.Id = @Id
38                OPTION ( OPTIMIZE FOR ( @Id = 1 ));
39
40            END;
41
42        IF @Id > 1
43            BEGIN
44
45                SELECT COUNT(*)
46                FROM   dbo.SkewedUp AS su
47                WHERE  su.Id = @Id
48                OPTION ( OPTIMIZE FOR ( @Id = 100000 ));
49
50            END;
51
52    END;
53
54
55EXEC dbo.if_logic @Id = 1
56
57EXEC dbo.if_logic @Id = 100000