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.