[SOLVED] diff two files based on part of lines

Issue

I have a file containing rows like

010203040506 azerty

020304050607 qwerty

and another file with rows like

xxxxxxxxxxxxxx 010203040506 yyyyyyyyyyyyyyyyyyyy

=> Files have millions of rows

=> How can I make something "like a diff" : get the first files rows but without the lines for which the number is in a line in the second file ? Like in my example the result should be

020304050607 qwerty

Solution

Thanks to KamilCuk answer and this link https://www.gnu.org/software/coreutils/manual/html_node/Paired-and-unpaired-lines.html I found join -v 1 file1 file2 to show only unpaired lines

Answered By - airti