Application:
Overall Process took around 4 Months with 6 rounds of interview. Recruiter was very pleasant, and helpful.
Interview :
First was a telephonic coding round. Asked to solve 3 questions (EMC) via coder pad. Standard and easy questions. Was moved forward for an in person interview, greeted very well. Needed to code for 1 Simple SQL and 1 complex PLSQL question (be prepared to write on wall). 1st and 2nd round Interviewers were very good and attentive to every detail i discussed, hinting me in presenting the code with proper syntax as they need to present documented proof. Finally, I was invited for an Onsite interview to finish the process which was scheduled after 4 weeks. I felt this process was very slow as they took time to get interviewers schedule aligned.
Onsite Interview:
First was behavioral, pretty decent with standard questions and a SQL query. Second was Application Design round. Very much interactive round and did not feel like an interview at any point and never knew how 45 min's passed by. I felt Interviewer was very impressed from his firm handshake and willingness to talk more on the same topic but bound by time. Lunch with a senior team member (felt he was a manager/track lead), had impressive discussion about the their tech stack and future roadmap and inquired about my areas of interests and personal targets.
Followed by 2 rounds of technical interview, to solve challenges using PLSQL. This is where I felt, interviewers were very much unprepared and were searching/thinking for questions to ask. I was happy to solve the challenge but was surprised when I was asked to write code for an algorithm which they lacked clarity. Moreover, the final technical interviewer was not even interested in having a conversation while I was trying to explain my approach to write sql query or function for the problem. He was all the time busy typing on his laptop with head down and least interested in interviewing me.
I was having a positive experience until lunch but after the 2 rounds of technical interview, I felt this interview was just a formality and they never had the intention to hire me.
Received negative feedback right next week of interview with a reason of insufficient technical skills.
Overall, though initially I felt bad at losing a chance to work for one of the challenging environment (atleast for what Facebook is known for), I digested the fact my interview was more of a formality to reject me and the hiring manager must have had already someone else ready for the role.
But in the end, I was happy I could convince 5 folks with my experience though i haven't been interviewed in last 6yrs and feel pity for the 2 interviewers.
Just concentrate on your basics and don't expect some crazy complex question. Questions, will be simple but tricky, will test your knowledge and experience.... keep solving challenges/algorithms from any coding blogs (don't restrict to a specific tech stack, solve challenges from all tech stacks).... which i feel is definitely a secret to success... All the best guys.