Consecutive days on a stored procedure in SQL Server 2008 R2?

Question

I've got the following line in a stored procedure when someone is logging into his account:

UPDATE AcccountsTable SET LogDate = getdate() WHERE AccID = @identity

However, I want to add a new feature where on every consecutive login day to add +1 to a new column ( ConsecutiveDays ) in my AccountsTable .

For example:

Day 1: 2018-04-11 20:00
Day 2: 2018-04-12 15:30
Day 3: 2018-04-13 10:20
and etc ....

Total consecutive days should be 3 days for the user account id that logged during these consecutive days.

If the user doesn't log on day 4 - 2018-04-14 but logs on the next day 2018-04-15 then all consecutive days should be reverted back to 1 .

I've searched for a similar solution for a stored procedure on MSSQL Server 2008 R2 but without success. I am not good at SQL at all, so I will appreciate your help a lot! Thank you in advance!

Answer 1

That shouldn't be too hard using case :

UPDATE AcccountsTable 
SET ConsecutiveDays = 
    CASE WHEN CAST(LogDate as Date) = CAST(DATEADD(DAY, -1, GETDATE()) As Date) 
              AND ConsecutiveDays < 28 THEN 
        ConsecutiveDays + 1 
    WHEN CAST(LogDate as Date) = CAST(GETDATE() as Date) THEN
        ConsecutiveDays 
    ELSE 
        1 
    END,
    ChallengesCompleted = 
    CASE WHEN ConsecutiveDays = 28 
              AND CAST(LogDate as Date) = CAST(DATEADD(DAY, -1, GETDATE()) As Date)
    THEN 
         ChallengesCompleted + 1
    ELSE
         ChallengesCompleted
    END,
    LogDate = GETDATE()
WHERE AccID = @identity