ClickHouse/docs/en/formats/pretty.rst

Pretty
------

Writes data as Unicode-art tables, also using ANSI-escape sequences for setting colors in the terminal.
A full grid of the table is drawn, and each row occupies two lines in the terminal. Each result block is output as a separate table. This is necessary so that blocks can be output without buffering results (buffering would be necessary in order to pre-calculate the visible width of all the values).
To avoid dumping too much data to the terminal, only the first 10,000 rows are printed. If the number of rows is greater than or equal to 10,000, the message "Showed first 10,000" is printed.
This format is only appropriate for outputting a query result, not for parsing.

The Pretty format supports outputting total values (when using WITH TOTALS) and extremes (when 'extremes' is set to 1). In these cases, total values and extreme values are output after the main data, in separate tables. Example (shown for the PrettyCompact format):

.. code-block:: sql

  SELECT EventDate, count() AS c FROM test.hits GROUP BY EventDate WITH TOTALS ORDER BY EventDate FORMAT PrettyCompact

.. code-block:: text

  ┌──EventDate─┬───────c─┐
  │ 2014-03-17 │ 1406958 │
  │ 2014-03-18 │ 1383658 │
  │ 2014-03-19 │ 1405797 │
  │ 2014-03-20 │ 1353623 │
  │ 2014-03-21 │ 1245779 │
  │ 2014-03-22 │ 1031592 │
  │ 2014-03-23 │ 1046491 │
  └────────────┴─────────┘
  
  Totals:
  ┌──EventDate─┬───────c─┐
  │ 0000-00-00 │ 8873898 │
  └────────────┴─────────┘
  
  Extremes:
  ┌──EventDate─┬───────c─┐
  │ 2014-03-17 │ 1031592 │
  │ 2014-03-23 │ 1406958 │
  └────────────┴─────────┘