Need to find the Max value in a SQL table and Based on the MAX value need to generate the Id's

Question

Member_Id    Interaction    Status
971053019         1          1
971053019         2          1
971053019         3          1
971053019         4          0
971053019         1          1
971053019         2          0
971053019         1          0
971053019         1          0
971053019         1          1
971053019         2          1
971053019         3          0
971053019         1          0

For the above table i need to generate the 1's to the status column

The key note here is..., we need to find the maximum value in the interaction column ...for that MAX value we need to update the status column as 0... and for the remaining rows it should be 1.

I have tried with SQL Aggregated Max Value function by doing grouping but i am unable to make the expected result set. Kindly any one help me with the SQL Script.

Answer 1

I think this is a kind of gaps-and-island problem. You want to set the flag on rows interaction is not greater that the "following" interaction .

For the question to make sense, you need a column that defines the ordering of the rows. This is not showing in your sample data, so I assumed id . Then, you can use lead() :

select 
    member_id,
    interaction,
    case when lead(interaction, 1, interaction) (over(partition by member_id order by id) > interaction     
        then 1 
        else 0 
    end as status
from mytable