read-from-csv.md

Got it 👍 You want Bash scripts to read content from a CSV file. I’ll show you different methods (basic → advanced), depending on what you want to do.

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1. Read line by line

#!/bin/bash

file="data.csv"

while IFS=, read -r col1 col2 col3
do
  echo "Column1: $col1 | Column2: $col2 | Column3: $col3"
done < "$file"

• IFS=, → sets delimiter to a comma
• read -r col1 col2 col3 → stores values in variables

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2. Skip header row

#!/bin/bash

file="data.csv"

tail -n +2 "$file" | while IFS=, read -r col1 col2 col3
do
  echo "Name: $col1, Age: $col2, City: $col3"
done

• tail -n +2 → starts reading from line 2 (skipping header).

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3. Read into array

#!/bin/bash

file="data.csv"

while IFS=, read -r -a row
do
  echo "Row: ${row[*]}"
done < "$file"

• Each row is stored in array row[].
• Access like ${row[0]}, ${row[1]}, etc.

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4. Extract a specific column

#!/bin/bash

file="data.csv"

cut -d, -f2 "$file"

• Prints only column 2 from CSV.

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5. Process with awk

#!/bin/bash

file="data.csv"

awk -F, '{ print "First: "$1 " | Second: "$2 " | Third: "$3 }' "$file"

• -F, sets delimiter as comma.
• $1, $2, $3 are fields.

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6. Example: CSV with Name, Age, City

data.csv

Name,Age,City
Alice,30,New York
Bob,25,London
Charlie,35,Paris

Script (reading into variables):

#!/bin/bash

file="data.csv"

tail -n +2 "$file" | while IFS=, read -r name age city
do
  echo "Name=$name | Age=$age | City=$city"
done

Output:

Name=Alice | Age=30 | City=New York
Name=Bob | Age=25 | City=London
Name=Charlie | Age=35 | City=Paris

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7. Handling quoted fields (with commas inside)

If CSV has "New York, USA" style fields:

#!/bin/bash

file="data.csv"

while IFS= read -r line
do
  echo "$line" | awk -F, -v OFS=" | " '{ print "Col1="$1,"Col2="$2,"Col3="$3 }'
done < "$file"

For complex CSV parsing with quotes/commas, it’s better to use Python or tools like csvkit.

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✅ With these scripts, you can:

• Read row by row
• Skip headers
• Extract columns
• Handle into arrays
• Use awk for processing

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Do you want me to make a general-purpose Bash CSV parser function (so you can pass file name + delimiter and get each row in variables)?