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28 lines
1 KiB
Markdown
28 lines
1 KiB
Markdown
# q
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> Execute SQL-like queries on CSV and TSV files.
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> More information: <https://harelba.github.io/q>.
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- Query a CSV file by specifying the delimiter as ',':
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`q {{[-d|--delimiter]}} ',' "SELECT * from {{path/to/file}}"`
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- Query a TSV file:
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`q {{[-t|--tab-delimited]}} "SELECT * from {{path/to/file}}"`
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- Query file with header row:
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`q {{[-d|--delimiter]}} {{delimiter}} {{[-H|--skip-header]}} "SELECT * from {{path/to/file}}"`
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- Read data from `stdin`; '-' in the query represents the data from `stdin`:
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`{{output}} | q "select * from -"`
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- Join two files (aliased as `f1` and `f2` in the example) on column `c1`, a common column:
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`q "SELECT * FROM {{path/to/file}} f1 JOIN {{path/to/other_file}} f2 ON (f1.c1 = f2.c1)"`
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- 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):
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`q {{[-D|--output-delimiter]}} {{delimiter}} {{[-O|--output-header]}} "SELECT {{column}} as {{alias}} from {{path/to/file}}"`
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