Bloomberg LP Interview Question for Software Engineer / Developers


Team: Supply Chain
Country: United States
Interview Type: In-Person




Comment hidden because of low score. Click to expand.
3
of 3 vote

Optimistic locking - We make a note of the record was read using the version number (or, other data such as time stamp, etc). When the record is written back we update the record if there are not changes in the version number. If the record is dirty, we fail the update transaction and ask the process to retry again. We also have to careful to make sure that the updates are atomic so as to not result in toctou software bug. This approach is usually used in high volume web based system that might use a stateless protocol like http.

Pessimistic locking - We lock the record at the time of reading. No other process can update the record until the lock is released. Once the record is done, transaction is closed and record is updated.

- Algorithmy December 06, 2014 | Flag Reply
Comment hidden because of low score. Click to expand.
0
of 0 vote

If database returns rows to the processes in same order then
Pth process processes row with index i if i%N=P and skips everything else

- Guest December 14, 2014 | Flag Reply
Comment hidden because of low score. Click to expand.
0
of 0 vote

Optimistic Locking assumes that the commits are frequent. However, no such information is provided here. Hence, it may not be used.

A simple solution is to create a new queue for the row whenever more than one process tries to access the row.

- Rajat Pawar January 20, 2015 | Flag Reply


Add a Comment
Name:

Writing Code? Surround your code with {{{ and }}} to preserve whitespace.

Books

is a comprehensive book on getting a job at a top tech company, while focuses on dev interviews and does this for PMs.

Learn More

Videos

CareerCup's interview videos give you a real-life look at technical interviews. In these unscripted videos, watch how other candidates handle tough questions and how the interviewer thinks about their performance.

Learn More

Resume Review

Most engineers make critical mistakes on their resumes -- we can fix your resume with our custom resume review service. And, we use fellow engineers as our resume reviewers, so you can be sure that we "get" what you're saying.

Learn More

Mock Interviews

Our Mock Interviews will be conducted "in character" just like a real interview, and can focus on whatever topics you want. All our interviewers have worked for Microsoft, Google or Amazon, you know you'll get a true-to-life experience.

Learn More