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q

Execute SQL-like queries on .csv and .tsv files. More information: https://harelba.github.io/q.
  • Query .csv file by specifying the delimiter as ',':
    q -d',' "SELECT * from {{path/to/file}}"
  • Query .tsv file:
    q -t "SELECT * from {{path/to/file}}"
  • Query file with header row:
    q -d{{delimiter}} -H "SELECT * from {{path/to/file}}"
  • Read data from stdin; '-' in the query represents the data from stdin:
    {{output}} | q "select * from -"
  • Join two files (aliased as f1 and f2 in the example) on column c1, a common column:
    q "SELECT * FROM {{path/to/file}} f1 JOIN {{path/to/other_file}} f2 ON (f1.c1 = f2.c1)"
  • Format output using an output delimiter with an output header line (note: command will output column names based on the input file header or the column aliases overridden in the query):
    q -D{{delimiter}} -O "SELECT {{column}} as {{alias}} from {{path/to/file}}"

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