Notes Archives - Coddicted

AWS Outposts

Feb

10

2023

AWS Outposts is a hybrid cloud service offered by Amazon Web Services (AWS) that allows customers to run AWS infrastructure and services on-premises. AWS Outposts provides the same hardware and infrastructure that is used in AWS data centers, and the same software, APIs, and tools that customers use in the cloud, making it easy for ...

AWS S3 object level file integrity

Feb

10

2023

AWS S3 object-level file integrity verification is a feature of Amazon S3 that provides a mechanism for verifying the integrity of objects stored in S3. The feature is useful for ensuring that data stored in S3 is accurate and complete, even if the data is transferred over a network or stored in S3 for an ...

Durability in Databases

Jan

30

2022

Durability is the process of persisting the writes that clients make to the database to a non-volatile storage disk. Caveat is that the writes should also be committed. This means once the commit has succeeded and right after that our system loses power or the system crashes and we need to restart, then our changes ...

Transaction Isolation

Jan

17

2022

The third of ACID properties “Isolation” is basically the question: “Can an in-progress transaction see changes made by another transaction running in-parallel?” Follow up to it would be “If yes, at what point of time can it see such changes?” Let’s try to analyse some aspects of the above question(s) from the db system implementation ...

Consistency in Databases

Jan

9

2022

It is one of the ACID properties which is often traded-off between different database systems (relational/ nosql/ graph etc.) (heard of eventually consistent DB?). It is often sacrificed for speed, scalability in some databases It can be categorised in two parts: Consistency in DataConsistency in Read Data Consistency That a transaction leaves the updated database ...

Atomicity

Dec

27

2021

Atomicity is one of the four ACID properties that define a database system. While ACID properties are usually referenced in Relational DBMS, they are still an applicable concept for nearly any database system out there. Let’s see what it is… All queries in a transaction must succeed. Like an atom (something which can’t be split)If ...

Database Transaction

Dec

22

2021

In this article we discuss about what is a Database Transaction, what are its intricacies and why it’s needed? A transaction is simply “a collection of SQL queries which are treated as a single unit of work.“ What is the need of a db transaction? Let’s think about the scenario where transactions were not possible, ...

Snowflake Practice questions

Nov

2

2021

Q.1 How does Snowflake store data internally? a. In CSV format b. In JSON format c. In a proprietary formatAns: c. proprietary format Q.2 Snowflake has tightly coupled storage and compute a. False b. TrueAns: a. False Q.3 The physical storage structure, compression and statistics of data is handled by DBAs? a. True b. FalseAns: ...

The ‘protected’ questions in Java…

Jul

3

2021

Let’s discuss a few questions about using protected in Java in combination with other keywords. Q1. Can we have methods declared as ‘protected final’ in Java? Q2. Protected members are not accessible outside the package. How do I write JUnits for them? Q1. Can we have methods declared as ‘protected final’ in Java? Short Answer: ...

Protected access modifier in Java

Jun

28

2021

As per the official java documentation from Oracle: “The protected modifier specifies that the member can only be accessed within its own package (as with package-private) and, in addition, by a subclass of its class in another package.” What this means is: Say, a concrete class Parent in package com.coddicted has a protected method named ...