(1) intersection of two files, and set the prerequisites: each file must not contain duplicate rows. retrieve the union of two files (only one copy of duplicate rows is retained) catfile1file2 | sort | uniq & gt; file32. extract the intersection of the two files (only files that exist in the two files at the same time are left...
(1) intersection of two files
Prerequisites: no duplicate rows are allowed in each file.
1. extract the union of the two files (duplicate rows only retain one copy)
Cat file1 file2 | sort | uniq> file3
2. extract the intersection of two files (only files that exist in both files are left)
Cat file1 file2 | sort | uniq-d> file3
3. delete the intersection and leave other rows.
Cat file1 file2 | sort | uniq-u> file3
(2) merge two files
A file is on, and a file is under
Cat file1 file2> file3
One file on the left and one file on the right
Paste file1 file2> file3
(3) remove duplicate rows from a file
Sort file | uniq
Note: repeat multiple rows is recorded as one row. that is to say, these duplicate rows are still present, but all are omitted as one row!
Sort file | uniq-u
The above command can remove all repeated lines, that is, non-repeated lines in the file!