mjhjmtu

array[1] is a string pulled from a 30k lines CSV:
example:

samsung black 2014

I need match those lines with one of the values contained within an array (arrayItems).

arrayItems contains 221 values like:

apple
sony
samsung

The actual script:

while IFS=$';' read -r -a array
do
 mapfile -t arrayItems < $itemsFile
 ## now loop through the above array
 for itemToFind in "$arrayItems[@]"
 do
 itemFound=""
 itemFound="$(echo $array[1] | grep -o '^$itemToFind')"
 if [ -n "$itemFound" ] 
 then 
 echo $itemFound 
 # so end to search in case the item is found
 break
 fi
 done
 # here I do something with $array[2], $array[4] line by line and so on, 
 # so I can't match the whole file $file_in at once but online line by line.
done < $file_in

The problem is that grep don't match.

but works If I try to hardcode $itemToFind like this:

itemFound="$(echo $array[1] | grep -o '^samsung')"

Another thing is... how to do it faster as $file_in is a 30k lines CSV?

You can use grep with file pattern option (-f)

Example:

$ echo -e "applensonynsamsung" > file_pattern
$ grep -f file_pattern your.csv

EDIT:
In response of your new contraints:

sed 's/^/^/g' $itemsFile > /tmp/pattern_file
while IFS=$';' read -r -a array
do
 echo $array[1] | grep -q -f /tmp/pattern_file.txt
 if [ $? -eq 0 ]; then 
 # here I do something with $array[2], $array[4] line by line and so on, 
 # so I can't match the whole file $file_in at once but online line by line.
 fi
done < $file_in

There are two errors in your script:

• grep tries to match the string $itemToFind because you put it between single quote '. Use double-quote instead.




• you are using an array from index 1 while help read tells it is starting at zero.

This should give this:

while IFS=$';' read -r -a array
do
 mapfile -t arrayItems < $itemsFile
 ## now loop through the above array
 for itemToFind in "$arrayItems[@]"
 do
 itemFound=""
 itemFound=$(echo $array[0] | grep -o "$itemToFind")
 if [ -n "$itemFound" ] 
 then 
 echo $itemFound 
 # so end to search in case the item is found
 break
 fi
 done
done < $file_in

EDIT:

If you want to make it faster, you can use extended regular expressions :

grep -E 'apple|sony|samsung' $file_in

And if you want to display only brands:

grep -E 'apple|sony|samsung' $file_in | awk 'print $1'