The first column of the shell is judged as duplicates, and only one of the data is taken.

For example 123456.txt content is as follows

90115601,2137786735 36684

90115601,2137786735 36684

90118301,17751822 34898

90145133,2050186877 3847

90145133,2050186877 3847

90151825,3580430507 37974

90151825,3580430507 37974

90188754,2987861307 24533

90188754,2987861307 24533

910910,1303405168 1855

910910,514876016 1555

991314,1879979639 49504

991314,4119267805 50922

998008,1453233015 13818

Take the first piece of data

TAC 123456.txt | awk-f, '!a[$1]++ ' |sort-t, '-k1

Take the last piece of data

Cat 123456.txt | awk-f, '!a[$1]++ ' |sort-t, '-k1

The first column of the shell is judged as duplicates, and only one of the data is taken.