# xan sort ```txt Sort CSV data, in ascending lexicographic order. For descending order, use the -R, --reverse flag. If you need numerical order instead, use the -N, --numeric flag. This requires reading all of the data into memory, unless using the -e/--external flag, which will be slower and fallback to using disk space. Usage: xan sort [options] [] sort options: --check Verify whether the file is already sorted. -s, --select Select a subset of columns to sort by. See 'xan select --help' for the format details. -N, --numeric Compare according to the numerical value of cells instead of the default lexicographic order. -R, --reverse Reverse sort order, i.e. descending order. -c, --count Number of times the line was consecutively duplicated. Needs a column name. Can only be used with --uniq. -u, --uniq When set, identical consecutive lines will be dropped to keep only one line per sorted value. -U, --unstable Unstable sort. Can improve performance. Does not work with -e/--external. -p, --parallel Whether to use parallelism to improve performance. -e, --external Whether to use external sorting if you cannot fit the whole file in memory. --tmp-dir Directory where external sorting chunks will be written. Will default to the sorted file's directory or "./" if sorting an incoming stream. -m, --memory-limit Maximum allowed memory when using external sorting, in megabytes. [default: 512]. -C, --cells Sort the selected cell values instead of the file itself, without re-ordering the columns. Runs in constant memory, can be streamed and can be used to e.g. make sure an edgelist always has the source & target keys in a consistent order. Common options: -h, --help Display this message -o, --output Write output to instead of stdout. -n, --no-headers When set, the first row will not be interpreted as headers. Namely, it will be sorted with the rest of the rows. Otherwise, the first row will always appear as the header row in the output. -d, --delimiter The field delimiter for reading CSV data. Must be a single character. ```