How to use Dense Rank and automatically generate dates - sql

Question

I have two questions in regards to DENSE_RANK and the other based on inserting dates. Basically I have 2 leagues with 4 teams per league. Each league has a round of fixtures like so:
League 1
Week1: 1v4, 2v3 - Date: 10-June-2016
Week2: 1v3, 2v4 - Date: 17-June-2016
Week3: 1v2, 3v4 - Date: 24-June-2016
League 2
Week1: 5v8, 6v7 - Date: 10-June-2016
Week2: 5v7, 6v8 - Date: 17-June-2016
Week3: 5v6, 7v8 - Date: 24-June-2016
(They play each other home and away)
Ok so league 1 and League 2 is (LeagueID 1 and League ID 2)
Week 1 and 2 are displayed under WeekNumber column
Teams 1 -8 have their own IDs (TeamID which is then displayed as HomeTeamID and AwayTeamID)
Date goes into a column which is FixtureDate
My questions are:
1- How under WeekNumber can I set it so that the group of games mentioned, it notices them as these games belong to week 1, these week 2, these games week 3 etc.
2- How to auto generate the date so that if week 1 is played 10 June 2016, the next round of fixtures are played 7 days later, then the round after 7 days later etc.
Below is what the table looks like currently:
WeekNumber HomeTeamID AwayTeamID FixtureWeek LeagueID
1 1 4 NULL 1
1 1 3 NULL 1
1 1 2 NULL 1
1 2 3 NULL 1
1 2 4 NULL 1
1 3 4 NULL 1
1 5 8 NULL 2
1 5 7 NULL 2
1 5 6 NULL 2
1 6 7 NULL 2
1 6 8 NULL 2
1 7 8 NULL 2
Below is what it should like:
WeekNumber HomeTeamID AwayTeamID FixtureWeek LeagueID
1 1 4 10-06-2016 1
2 1 3 17-06-2016 1
3 1 2 24-06-2016 1
1 2 3 10-06-2016 1
2 2 4 17-06-2016 1
3 3 4 24-06-2016 1
1 5 8 10-06-2016 2
2 5 7 17-06-2016 2
3 5 6 24-06-2016 2
1 6 7 10-06-2016 2
2 6 8 17-06-2016 2
3 7 8 24-06-2016 2
Below is my current code which needs to be modified but I need help with this:
CREATE PROCEDURE [dbo].[Fixture_Insert]
#LeagueID INT
AS
SET NOCOUNT ON
BEGIN
INSERT INTO dbo.Fixture (WeekNumber, HomeTeamID, AwayTeamID, FixtureWeek, LeagueID)
SELECT
ROW_NUMBER() OVER (ORDER BY a.LeagueID) AS WeekNumber,
h.TeamID,
a.TeamID,
NULL AS FixtureWeek, -- Don't know what to set this to for automatic dates
h.LeagueID
FROM dbo.Team h
CROSS JOIN dbo.Team a
WHERE h.TeamID <> a.TeamID
AND h.LeagueID = a.LeagueID
END
UPDATE:
I've applied images to showcase what is happening so you can see what needs to be done to fix it (the table displayed is when I did a select* from dbo.Fixture):
The proc I excuted for the above is displayed here:

Answer 1

DECLARE #StartFixtureWeek date = '2016-06-10'
;WITH team AS (
SELECT *
FROM (VALUES
(1,1),(2,1),(3,1),(4,1),(5,2),(6,2),(7,2),(8,2)
) as t (teamid, leagueid)
)
, cte AS (
SELECT h.teamid AS HomeTeamID,
a.teamid AS AwayTeamID,
h.leagueid AS LeagueID
FROM team h
CROSS JOIN team a
WHERE h.teamid != a.teamid AND h.leagueid = a.leagueid
), final AS (
SELECT ROW_NUMBER() OVER (PARTITION BY c.LeagueID ORDER BY c.LeagueID, c.HomeTeamID, c.AwayTeamID) as rn,
c.HomeTeamID,
c.AwayTeamID,
c.LeagueID
FROM cte c
CROSS APPLY (
SELECT TOP 1 a.HomeTeamID, a.AwayTeamID
FROM cte a
WHERE a.LeagueID= c.LeagueID and a.AwayTeamID=c.HomeTeamID and a.HomeTeamID =c.AwayTeamID
ORDER BY a.HomeTeamID, a.LeagueID) as b
WHERE c.HomeTeamID < b.HomeTeamID
)
SELECT CASE WHEN rn > 3 THEN rn-3 ELSE rn END as WeekNumber,
HomeTeamID,
AwayTeamID,
CAST(DATEADD(week,(CASE WHEN rn > 3 THEN rn-3 ELSE rn END)-1,#StartFixtureWeek) as date) FixtureWeek,
LeagueID
FROM final
Output:
WeekNumber HomeTeamID AwayTeamID FixtureWeek LeagueID
-------------------- ----------- ----------- ----------- -----------
1 1 2 2016-06-10 1
2 1 3 2016-06-17 1
3 1 4 2016-06-24 1
1 2 3 2016-06-10 1
2 2 4 2016-06-17 1
3 3 4 2016-06-24 1
1 5 6 2016-06-10 2
2 5 7 2016-06-17 2
3 5 8 2016-06-24 2
1 6 7 2016-06-10 2
2 6 8 2016-06-17 2
3 7 8 2016-06-24 2
(12 row(s) affected)

Answer 2

Add a parameter to your stored procedure called #StartFixtureWeek DATETIME
Then you can use DATEADD
CREATE PROCEDURE [dbo].[Fixture_Insert]
#LeagueID INT,
#StartFixtureWeek DATETIME
AS
SET NOCOUNT ON
BEGIN
INSERT INTO dbo.Fixture (WeekNumber, HomeTeamID, AwayTeamID, FixtureWeek, LeagueID)
SELECT
ROW_NUMBER() OVER (ORDER BY a.LeagueID) AS WeekNumber,
h.TeamID,
a.TeamID,
SELECT DATEADD(day,(ROW_NUMBER() OVER (ORDER BY a.LeagueID)-1)*7,#StartFixtureWeek) AS FixtureWeek,
h.LeagueID
FROM dbo.Team h
CROSS JOIN dbo.Team a
WHERE h.TeamID <> a.TeamID
AND h.LeagueID = a.LeagueID
END