2023-12-20

mongodb

Notes

In many databases the UPDATE operation is actually split into DELETE and INSERT But in mongo update() occurs in memory. So it is in place. Then it is lazily written to disk. Mongo only writes once per second

Questions

Question 1: What is the full form of NoSQL

Question 2: Give the types of NoSQL databases and their respective examples

Question 3: What are the advantages of NoSQL?

Question 4: Differentiate between SQL and NoSQL

Question 5: Difference in terms schema

Question 6: Difference in terms of scaling

Question 7: Difference in terms of data storage

Question 8: Difference in terms of ACID compliance

Question 9: What is mongoDB? Give those six points

Question 10: Why mongoDB?

Question 11: What format does mongoDB use to store data on disk?

Question 12: What is _id in mongoDB?

Question 13: Give the equivalent structure to database, table and row in mongoDB

Question 14: What is the size limit of a BSON document

Question 15: How do you store large binary data in mongo?

Question 16: What is the default chunk size in gridFS?

Question 17: How many collections does gridFS use to store large data and what are they?

Question 18: What are the 4 members in a replica set?

Question 19: Can an arbiter be the primary?

Question 20: Can a delayed secondary be the primary?

Question 21: Is replication synchronous or async in mongo?

Question 22: What is the use of delayed secondary?

Question 23: delayed secondary’s state reflects the current state of the members. True or False?

Question 24: Draw a diagram illustrating the replication process of mongoDB

Question 25: What is in-place updates in mongo

Question 26: How does an UPDATE statement work under the hood in most RDBMS?

Question 27: Mongo writes to disk every $\underline{\hspace{3cm}}$

Question 28: Mention the database client and server for mySQL, Oracle and mongoDB

Question 29: What are the 13 data types in mongo

Question 30: What are the two parameters taken by find()

Question 31: What are the relational operators in mongo

Question 32: Give regex for finding some characters that occur at the start, end and in any positions

Question 33: How do you display the last 5 records

Question 34: Display only the second and third records

Question 35: Check a specific index of an array

Question 36: Check the size of an array

Question 37: Illustrate with an example the difference between using $all and just comparing using an array

Question 38: Remove the last element of an array

Question 39: Remove the first element of an array

Question 40: Update the second index of an array

Question 41: Add elements to an array - 2 ways

Question 42: What is the difference between $addToSet and $push

Question 43: $pull vs pullAll

Question 44: How many documents are printed if the cursor object is not assigned to anything?