Awk Examples

awk_examples.sh

#!/usr/bin/env bash

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# Grab a field

# echo "hello world this is Bryan" | awk '{print $1,$5}'

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# Grab a column

# echo "ajay manager account 45000
# sunil clerk account 25000
# varun manager sales 50000
# amit manager account 47000
# tarun peon sales 15000
# deepak clerk sales 23000
# sunil peon sales 13000
# satvik director purchase 80000" | awk '{print}' #adding $4 grabs a column


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# Selectively output fields


# echo "ajay manager account 45000
# sunil clerk account 25000
# varun manager sales 50000
# amit manager account 47000
# tarun peon sales 15000
# deepak clerk sales 23000
# sunil peon sales 13000
# satvik director purchase 80000" | awk '/manager/ {print}'


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# Variables

# $0 -- The whole line

# echo "Hello World" | awk '{print $0}'

# NR -- The Number of Records


# echo "ajay manager account 45000
# sunil clerk account 25000
# varun manager sales 50000
# amit manager account 47000
# tarun peon sales 15000
# deepak clerk sales 23000
# sunil peon sales 13000
# satvik director purchase 80000" | awk '{print NR}' # Adding $ to NR behaviour or adding ,$0

# NF -- Number of Fields


# echo "ajay manager account 45000
# sunil clerk account 25000
# varun manager sales 50000
# amit manager account 47000
# tarun peon sales 15000
# deepak clerk sales 23000
# sunil peon sales 13000
# satvik director purchase 80000" | awk '{print NF}' # Behavior of $1,NF and of $NF


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# Format some output


# echo "ajay manager account 45000
# sunil clerk account 25000
# varun manager sales 50000
# amit manager account 47000
# tarun peon sales 15000
# deepak clerk sales 23000
# sunil peon sales 13000
# satvik director purchase 80000" | awk '{print NR " - " $1}'

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# BEGIN and END

# BEGIN and END are special conditionas that only get triggered once per run

# BEGIN gets triggered before processing any line
# END gets triggered after all lines have been processed


# echo "ajay manager account 45000
# sunil clerk account 25000
# varun manager sales 50000
# amit manager account 47000
# tarun peon sales 15000
# deepak clerk sales 23000
# sunil peon sales 13000
# satvik director purchase 80000" | awk '{print NR}' # Add BEGIN & END


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# Setting a delimiter


# echo "ajay/manager/account/45000
# sunil/clerk/account/25000
# varun/manager/sales/50000
# amit/manager/account/47000
# tarun/peon/sales/15000
# deepak/clerk/sales/23000
# sunil/peon/sales/13000
# satvik/director/purchase/80000" | awk -F/ '{print $1,$4}' # -F can take regex '[,-/]'