Add Count The Lines In A CSV Where A Column Is Empty as a Unix TIL

unix/count-the-lines-in-a-csv-where-a-column-is-empty.md

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+# Count The Lines In A CSV Where A Column Is Empty
+
+The [`xsv` utility](https://github.com/BurntSushi/xsv) is a fast way to analyze
+and work with CSV files from the command line.
+
+With the `search` subcommand, I can seach for lines that match a pattern and
+even narrow that search to focus on a selected column.
+
+For instance, to search for any lines where column 3 is empty:
+
+```
+$ xsv search -s 3 '^$' data.csv
+```
+
+The `-s 3` narrows the search to just column 3. The `'^$'` regex pattern
+matches on cells where there is the start character (`^`) and end character
+(`$`) with nothing in between, hence empty.
+
+I can then pipe that to `wc -l` to get a count of the number of empty lines.
+
+```
+$ xsv search -s 3 '^$' data.csv | wc -l
+```
+
+See `xsv search --help` for more details.