Can my favourite team still become Football Champion (XML)?, Sql Server

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SET NOCOUNT ON;
--USE tempdb;
USE rextester;
GO
IF SCHEMA_ID('my') IS NULL EXEC('CREATE SCHEMA my');
ELSE BEGIN
  IF OBJECT_ID('my.f', 'IF') IS NOT NULL DROP FUNCTION my.f;
  IF OBJECT_ID('my.s', 'U') IS NOT NULL DROP TABLE my.s;
  IF OBJECT_ID('my.m', 'U') IS NOT NULL DROP TABLE my.m;
  IF OBJECT_ID('my.c', 'U') IS NOT NULL DROP TABLE my.c;
END;
GO
CREATE TABLE my.c( -- Test cases
  c INT PRIMARY KEY CLUSTERED CHECK(c > 0), -- Test Case Id
  n INT CHECK(n > 0), -- Current position of the team of interest
);
CREATE TABLE my.s( -- Standings
  a INT FOREIGN KEY REFERENCES my.c(c) CHECK(a > 0), -- Test cAse Id
  p INT CHECK(p > 0) -- Team pts
);
CREATE TABLE my.m( -- Matches
  s INT FOREIGN KEY REFERENCES my.c(c) CHECK(s > 0), -- Test caSe Id
  i INT CHECK(i > 0), -- Team i
  j INT CHECK(j > 0), -- Team j
  CHECK(i != j)
);
GO
INSERT my.c(c, n) VALUES (1, 2), (2, 1), (3, 3), (4, 2), (5, 2), (6, 1), (7, 2);
INSERT my.s(a, p) VALUES (1, 93), (1, 86), (1, 78), (1, 76), (1, 75),
(2, 50), (3, 10), (3, 10), (3, 10), (4, 15), (4, 10), (4, 8),
(5, 10), (5, 9), (5, 8), (6, 10), (6, 9), (6, 9), (7, 21), (7, 12), (7, 11);
INSERT my.m(s, i, j) VALUES (1, 1, 2), (1, 4, 3), (1, 2, 3), (1, 3, 2), (1, 1, 2),
(4, 2, 3), (4, 1, 3), (4, 1, 3),(4, 3, 1), (4, 2, 1), (6, 2, 3), (6, 3, 2),
(7, 2, 1), (7, 1, 2), (7, 2, 3), (7, 1, 3), (7, 1, 3), (7, 3, 1), (7, 3, 1);
GO
CREATE FUNCTION my.f(@s XML,@m XML,@ INT)RETURNS TABLE RETURN
WITH s AS(SELECT s.value('@p','INT')p FROM @s.nodes('S')s(s)),
m AS(SELECT m.value('@i','INT')i,m.value('@j','INT')j FROM @m.nodes('M')m(m)),
a AS(SELECT ROW_NUMBER()OVER(ORDER BY-p)t,p FROM s),
b AS(SELECT p+3*(SELECT COUNT(*)FROM m WHERE t IN(i,j))o FROM a WHERE t=@),
c AS(SELECT i,j,ROW_NUMBER()OVER(ORDER BY 1/0)k FROM m WHERE @ NOT IN(i,j)),
d AS(SELECT COUNT(*)u,POWER(3,COUNT(*))-1 v FROM c UNION ALL SELECT u,v-1 FROM d WHERE v>0),
e AS(SELECT v,u,v/3 q,v%3 r FROM d UNION ALL SELECT v,u-1,q/3,q%3 FROM e WHERE u>1),
f AS(SELECT v,p+SUM(IIF(t=i,r,(2-r))%3*3/2)s FROM a,c,e WHERE t IN(i,j)AND k=u GROUP BY v,t,p),
g AS(SELECT MAX(s)x FROM f GROUP BY v)SELECT SUM(IIF(o<ISNULL(x,p),0,1))f FROM a,(b OUTER APPLY g)WHERE t=1;
GO
SELECT c, f
FROM my.c
OUTER APPLY(SELECT p FROM my.s S WHERE a = c FOR XML AUTO)S(s)
OUTER APPLY(SELECT i, j FROM my.m M WHERE s = c FOR XML AUTO)M(m)
OUTER APPLY my.f(s, m, n)
ORDER BY c
OPTION(MAXRECURSION 0);

View schema
Execution time: 0,12 sec, rows selected: 0, rows affected: 0, absolute service time: 0,27 sec