Merge Course Batch Data - Implementation Design

Impacted tables - content_consumption, user_courses

Data Model

    batchid text,
    userid text,
    active boolean,
    addedby text,
    completedon timestamp,
    completionpercentage int,
    contentstatus map<text, int>,
    courseid text,
    datetime timestamp,
    delta text,
    enrolleddate text,
    grade text,
    lastreadcontentid text,
    lastreadcontentstatus int,
    progress int,
    status int,
    PRIMARY KEY (batchid, userid)
    CLUSTERING ORDER BY (userid ASC)

	userid text,
    contentid text,
    batchid text,
    courseid text,
    completedcount int,
    contentversion text,
    datetime timestamp,
    grade text,
    lastaccesstime text,
    lastcompletedtime text,
    lastupdatedtime text,
    progress int,
    result text,
    score text,
    status int,
    viewcount int,
    PRIMARY KEY (userid, contentid, batchid, courseid)
    CLUSTERING ORDER BY (contentid ASC, batchid ASC, courseid ASC)

Workflow

1. Get data from content_consumption table where userId = fromAccountId
2. Check whether toAccountId is present in content_consumption in the same combination - fromAccountId toAccountId, contentId, batchId, courseId 
   1. Yes - Update status of toAccountId record in content_consumption with highest status of 2 records(statuses of fromAccountId and toAccountId records)
   2. No - Insert record in content_consumption table with data fetched in step 1, with toAccountId replacing fromAccountId for the userId field
3. Delete the record(of fromAccountId) fetched in step 1 from content_consumption table
4. Get data from user_courses where batchId = dataFetchedInStep1 and userId = fromAccountId
5. Check whether toAccountId is present in user_courses table for the same batchId
   1. Yes - Ignore
   2. No - Insert record in user_courses table with data fetched in step 4, with toAccountId replacing fromAccountId for the userId field
6. Delete the record(of fromAccountId) fetched in step 4 from user_courses table
7. Generate event and push to Kafka topic