# Output settings Output settings control binary containers, display tables, image dimensions, Markdown, and generated SQL. Each setting applies only to the formats listed in its section. Use a statement `SETTINGS` clause. Defaults in `system.settings` are read-only; format settings cannot be persisted with `SET`. Put input settings before `FORMAT`, because the bytes after the format name are input data. ## arrow_compression Type: `String` Default value: `lz4_frame` Compress record batch buffers with lz4_frame or zstd; none writes uncompressed buffers. Applies to: `arrow`, `arrow_stream`. ## arrow_date_as_number Type: `Bool` Default value: `0` Write Date as UInt16 days since the epoch instead of Date32; Date32 always remains Date32. Applies to: `arrow`, `arrow_stream`. ## arrow_dictionary Type: `Bool` Default value: `0` Write LowCardinality as dictionary indices and values instead of expanding its scalars. Applies to: `arrow`, `arrow_stream`. ## arrow_dictionary_64bit_indices Type: `Bool` Default value: `0` Use 64-bit dictionary indices instead of the smallest width that fits the dictionary. Applies to: `arrow`, `arrow_stream`. ## arrow_dictionary_signed_indices Type: `Bool` Default value: `1` Use signed dictionary indices; when off, use unsigned indices. Applies to: `arrow`, `arrow_stream`. ## arrow_fixed_strings Type: `Bool` Default value: `1` Write FixedString with a fixed byte width instead of variable-length Binary. Applies to: `arrow`, `arrow_stream`. ## arrow_strings_as_text Type: `Bool` Default value: `1` Write text strings as Utf8 instead of Binary; byte strings keep their exact bytes. Applies to: `arrow`, `arrow_stream`. ## markdown_escape_special_characters Type: `Bool` Default value: `0` Escape ASCII punctuation in text and byte-string values with a backslash; when off, escape controls, backslashes, and single quotes. Applies to: `markdown`. ## parquet_compression Type: `String` Default value: `zstd` Compress column pages with snappy, lz4, brotli, zstd, gzip, or none. Applies to: `parquet`. ## parquet_fixed_strings Type: `Bool` Default value: `1` Write FixedString as fixed-width bytes instead of variable-width Binary. Applies to: `parquet`. ## parquet_page_bytes Type: `UInt64` Default value: `1048576` Target uncompressed bytes per output data page. Applies to: `parquet`. ## parquet_page_index Type: `Bool` Default value: `1` Write column and offset indexes for individual data pages. Applies to: `parquet`. ## parquet_row_group_bytes Type: `UInt64` Default value: `536870912` Target output row-group bytes before compression. Applies to: `parquet`. ## parquet_row_group_rows Type: `UInt64` Default value: `1000000` Maximum rows per output row group. Applies to: `parquet`. ## parquet_strings_as_text Type: `Bool` Default value: `1` Annotate text strings as UTF-8; BLOB keeps its exact binary representation. Applies to: `parquet`. ## parquet_wide_as_decimal Type: `Bool` Default value: `0` Write 128/256-bit integers as big-endian DECIMAL instead of little-endian fixed-width bytes. Applies to: `parquet`. ## parquet_write_batch_rows Type: `UInt64` Default value: `1024` Check output data-page size after this many rows. Applies to: `parquet`. ## parquet_write_geo Type: `Bool` Default value: `1` Encode geometry as WKB and include GeoParquet column metadata. Applies to: `parquet`. ## png_height Type: `UInt64` Default value: `1024` Height of the image in pixels, from 1 through 2147483647. Applies to: `png`. ## png_time_denominator Type: `UInt64` Default value: `60` Positive denominator of the duration in seconds of one integer t unit. Applies to: `png`. ## png_time_numerator Type: `UInt64` Default value: `1` Positive numerator of the duration in seconds of one integer t unit. Applies to: `png`. ## png_width Type: `UInt64` Default value: `1024` Width of the image in pixels, from 1 through 2147483647. Applies to: `png`. ## pretty_borders Type: `String` Default value: `unicode` The characters that draw the table: unicode for box-drawing lines, ascii for plus, minus, and bar. Applies to: `pretty_compact`. ## pretty_footer_from_rows Type: `UInt64` Default value: `0` Repeat the column names in the bottom border when the table shows at least this many rows; 0 never repeats them. Applies to: `pretty_compact`. ## pretty_max_cell_width Type: `UInt64` Default value: `0` Cut a value wider than this many terminal columns and mark the cut; 0 never cuts. Applies to: `pretty_compact`. ## pretty_max_padding Type: `UInt64` Default value: `0` Align a column to at most this many terminal columns; wider values extend their own row. 0 aligns to the widest value. Applies to: `pretty_compact`. ## pretty_max_rows Type: `UInt64` Default value: `0` Show at most this many rows and report how many were left out; 0 shows every row. Applies to: `pretty_compact`. ## pretty_row_numbers Type: `Bool` Default value: `0` Add a first column that numbers the rows from 1. Applies to: `pretty_compact`. ## sql_insert_batch_rows Type: `UInt64` Default value: `65505` Write at most this many rows per INSERT or REPLACE statement; 0 writes one row per statement. Applies to: `sql_insert`. ## sql_insert_column_names Type: `Bool` Default value: `1` Include the result column names before VALUES in each written statement. Applies to: `sql_insert`. ## sql_insert_quote_names Type: `Bool` Default value: `1` Surround each written column name with backticks; names and the table text are otherwise written verbatim. Applies to: `sql_insert`. ## sql_insert_replace Type: `Bool` Default value: `0` Write REPLACE INTO instead of INSERT INTO. Applies to: `sql_insert`. ## sql_insert_table Type: `String` Default value: `table` The table text written verbatim after INSERT INTO or REPLACE INTO; include any desired qualification or quoting. Applies to: `sql_insert`. ## sqlite_write_table Type: `String` Default value: `table` Name of the single table written to the output database. Applies to: `sqlite`.