csvjoin - csvjoin Documentation

       Christopher Groskopf and contributors

       2016, Christopher Groskopf and James McKinney

2.0.1                                             Jul 12, 2024                                        CSVJOIN(1)

       Merges  two  or  more  CSV  tables together using a method analogous to SQL JOIN operation. By default it
       performs an inner join, but full outer, left outer, and right outer are also  available  via  flags.  Key
       columns  are  specified  with  the  -c  flag  (either  a  single  column which exists in all tables, or a
       comma-separated list of columns with one corresponding to each). If the columns flag is not provided then
       the tables will be merged "sequentially", that is they will be merged in row order with no filtering:

          usage: csvjoin [-h] [-d DELIMITER] [-t] [-q QUOTECHAR] [-u {0,1,2,3}] [-b]
                         [-p ESCAPECHAR] [-z FIELD_SIZE_LIMIT] [-e ENCODING] [-L LOCALE]
                         [-S] [--blanks] [--null-value NULL_VALUES [NULL_VALUES ...]]
                         [--date-format DATE_FORMAT] [--datetime-format DATETIME_FORMAT]
                         [-H] [-K SKIP_LINES] [-v] [-l] [--zero] [-V] [-c COLUMNS]
                         [--outer] [--left] [--right] [-y SNIFF_LIMIT] [-I]
                         [FILE [FILE ...]]

          Execute a SQL-like join to merge CSV files on a specified column or columns.

          positional arguments:
            FILE                  The CSV files to operate on. If only one is specified,
                                  it will be copied to STDOUT.

          optional arguments:
            -h, --help            show this help message and exit
            -c COLUMNS, --columns COLUMNS
                                  The column name(s) on which to join. Should be either
                                  one name (or index) or a comma-separated list with one
                                  name (or index) per file, in the same order in which
                                  the files were specified. If not specified, the two
                                  files will be joined sequentially without matching.
            --outer               Perform a full outer join, rather than the default
                                  inner join.
            --left                Perform a left outer join, rather than the default
                                  inner join. If more than two files are provided this
                                  will be executed as a sequence of left outer joins,
                                  starting at the left.
            --right               Perform a right outer join, rather than the default
                                  inner join. If more than two files are provided this
                                  will be executed as a sequence of right outer joins,
                                  starting at the right.
            -y SNIFF_LIMIT, --snifflimit SNIFF_LIMIT
                                  Limit CSV dialect sniffing to the specified number of
                                  bytes. Specify "0" to disable sniffing.
            -I, --no-inference    Disable type inference when parsing CSV input.

          Note that the join operation requires reading all files into memory. Don't try
          this on very large files.

       See also: Argumentscommontoalltools.

          csvjoin -c 1 examples/join_a.csv examples/join_b.csv

       Add two empty columns to the right of a CSV:

          echo "," | csvjoin examples/dummy.csv -

       Add a single column to the right of a CSV:

          echo "new-column" | csvjoin examples/dummy.csv -

       csvjoin - csvjoin Documentation