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01: 14 Unix must-know interview Q&As

Q1 How do you remove the Control-M characters from a file? A1 Using the sed command that replaces Control-M with nothing Note: The ^M is typed on the command line...



02: Top 10 Linux interview Q&As

Many production systems run on Linux systems, especially the Cloud infrastructure (i.e. AWS & GCP). Even Android uses the Linux kernel under the hood. So, it really pays to have...



03: Shell script interview Q&As for Java developers

Q1 How will you go about reading a CSV file as shown below? A1 Q2 How will you read and then write to another file? … Read more ›...



12 SSH interview Q&As

Q1. What is ssh? A1. SSH is a secure protocol used for remotely connecting to Linux servers. For example, creating an ssh connection from your local laptop to an ec2...



5 curl vs wget interview Q&As

Q1. What are the differences between curl & wget? A1. wget is a tool to download files from servers. It let’s you download files from an HTTP/HTTPS or FTP server....



Hidden Unix, Git & SVN config files

You need to use “ls -la” to list the hidden files in your home (i.e ~) directory. These config files are “.bashrc”, “.inputrc”, “.profile”, etc. In computing, a hidden folder or hidden file is a folder or file that does not display by default when showing a directory/file listing.

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sed and awk to write shell scripts for Java developers

Q. How would you go about replacing a piece of a text or a phrase from 20,000+ web templates residing on a Unix file system? Even some candidates with 5+...



Unix – combining two or more files & output only a subset of columns

Unix is a very powerful tool to automate monotonous & manual tasks. Here is a real-life example for data engineers & software engineers. If you are not familiar with Shell scripting the code may look complex,

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Unix – Convert csv to psv without removing commas within quotes

Unix is a very powerful tool to automate monotonous & manual tasks. Here is a real-life example for data engineers & software engineers. If you are not familiar with Shell scripting the code may look complex,

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Unix – Working with SQL files

Q01 How will you go about to list all the table names used in a number of sql scripts for a given database say MY_DB_1?
A01 Let’s say you have a number of sample sql scripts like

test.sql:

test2.sql:

Output_table_names_used_in_scripts.sh

Output.txt

Q02 How will you go about replacing the database name MY_DB_1 in the *.sql above to use MY_NEW_DEV_DB ?

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Unix history commands for Java developer productivity

When you are using Linux/Unix command line frequently, using the history effectively can be a major productivity boost. You can accomplish things with less typing. For example, you will be typing lots of commands like

and so on.

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Unix remoting interview Q&A for Java developers

Q1 How will you delete files that are older than 7 days in a remote unix server? A1 By ssh ing to the remote host server Q2 How will you...



Unix sed & awk commands in action

This extends sed and awk to write shell scripts for Java developers. sed & awk are very powerful tool for data engineers to transform text files. Here are a few...



Unix Sed commands for Java developers

sed (stream editor) is one of the powerful workhorse commands in UNIX. Recently I had to use it with “Git” and “Maven” to find text “SNAPSHOT”

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Unix shell script to upload & download data between HDFS and edge node

In BigData projects relating to HDFS or AWS S3, it is common to have scripts that transfer or download data from HDFS to the local file system on an edge...



What does this Unix code snippet do?

Data Engineers & Java Developers must have a good handle on Unix. Most production systems are Linux based with 1000’s of scripts.

date

Q01. What does the below Unix code do?

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800+ Java Interview Q&As

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