MySQL loop for total score each week - mysql

Question

The following statement outputs the userName and week1Score. I would like it to loop through 17 times, to get the score for each of the 17 weeks.
SELECT userName, (totalWins+(totalPushs*.5)) AS week1Score FROM (
SELECT *, SUM(win) AS totalWins, SUM(lost) AS totalLost, SUM(push) AS totalPushs FROM (
SELECT *, (finalResult = 'win') AS win, (finalResult = 'loss') AS lost, (finalResult = 'push') AS push FROM (
SELECT userName, IF (pickID=visitorID, visitorResult, homeResult) AS finalResult
FROM table_users
JOIN table_picks
ON table_users.userID = table_picks.userID
JOIN table_schedule
ON table_picks.gameID = table_schedule.gameID
WHERE weekNum = 1
) x
) x GROUP BY userName
) x ORDER BY userName
The above statement outputs the following.
+-----------------------+
| userName | week1Score |
+-----------------------+
I would like it to loop through 17 times to to output the following.
+------------------------------------------------------------------------+
| userName | week1Score | week2Score | week3Score | week4Score | week... |
+------------------------------------------------------------------------+
How would I use MySQL loop to do this?

Answer 1

I think your query is a bit complex. However, there's a better approach: a Pivot Query.
MySQL does not have a "pivot" instruction, but an expression can be built to get the output you need.
I'll build a temp table to make things a bit easier to read (I am using user variables to make things a bit clearer):
-- This first table will compute the score
drop table if exists temp_step01;
create temporary table temp_step01
select userId
, userName
, weekNum
, #finalResult := if(pickId=visitorId, visitorResult, homeResult) as finalResult
, #w := #finalResult = 'win' as win
, #l := #finalResult = 'loss' as lost
, #p := #finalResult = 'push' as push
, #w + (#p * 0.5) as score
from
table_users as tu
join table_picks as tp on tu.userId = tp.userId
join table_schedule as ts on tp.gameId = ts.gameId;
alter table temp_step01
add index uid(userId),
add index wn(weekNum);
Now, the fun part: build the pivot table
-- First, build the expression for each column
select
group_concat(
concat(
'sum(case weekNum when ', weekNum, ' then score end) as week', weekNum, 'score'
)
)
into #sql
from (select distinct weekNum from temp_step01) as a;
-- Then, create a complete SELECT statement
set #sql = concat('select userId, userName, ', #sql, ' from temp_step01 group by userId');
-- OPTIONAL: Check that the sql statement is well written:
select #sql;
-- Now, prepare a statement, and execute it
prepare stmt from #sql;
execute stmt;
-- When you're done, don't forget to deallocate the statement
deallocate prepare stmt;
A bit laborious, but I think this will give you what you need. Hope it helps.