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14 Top Data Pipeline Key Terms Explained

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 Here are some key terms commonly used in data pipelines 1. Data Sources Definition: Points where data originates (e.g., databases, APIs, files, IoT devices). Examples: Relational databases (PostgreSQL, MySQL), APIs, cloud storage (S3), streaming data (Kafka), and on-premise systems. 2. Data Ingestion Definition: The process of importing or collecting raw data from various sources into a system for processing or storage. Methods: Batch ingestion, real-time/streaming ingestion. 3. Data Transformation Definition: Modifying, cleaning, or enriching data to make it usable for analysis or storage. Examples: Data cleaning (removing duplicates, fixing missing values). Data enrichment (joining with other data sources). ETL (Extract, Transform, Load). ELT (Extract, Load, Transform). 4. Data Storage Definition: Locations where data is stored after ingestion and transformation. Types: Data Lakes: Store raw, unstructured, or semi-structured data (e.g., S3, Azure Data Lake). Data Warehous...
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Tail Command in Linux: A Comprehensive Overview

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The tail in Linux is handy command. You can check the last lines of a file in Linux/Unix operating systems.

You can use it to display last lines from single file, display last lines from multiple files, display the last entries of log files.


Tail Command in Linux


During production support the usage of Tail command is helpful since you can check latest logs quickly. Here are the top Tail command examples.

#1 Display last lines in a file (Tail file Linux)


Here's the tail command that shows last three lines of a file.

cat sample.txt | tail -3

It displays last 3 lines of a file. The same command you can use as

tail -3 sample.txt

#2 Display last lines of multiple files


There are three files. sample2.txt, sample3.txt, sample4.txt. The command displays the last 3 lines from all the three files.

tail -3 sample[2-4].txt


Tail command


#3 Tail -f option (Tail f Linux)


The –f option is to check status of long-running process that is redirecting output to a file. For example, if you invoke the below command, the status it writes to the output.

find . -print |xargs grep -i abc </tmp/abc &

Using the -f option you can see contents of the file /tmp/abc whenever it is updated: 

tail -f /tmp/abc


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