Don't cut single value in Pretty formats.

src/Core/Settings.h

@@ -1090,6 +1090,7 @@ class IColumn;
     M(UInt64, output_format_pretty_max_rows, 10000, "Rows limit for Pretty formats.", 0) \
     M(UInt64, output_format_pretty_max_column_pad_width, 250, "Maximum width to pad all values in a column in Pretty formats.", 0) \
     M(UInt64, output_format_pretty_max_value_width, 10000, "Maximum width of value to display in Pretty formats. If greater - it will be cut.", 0) \
+    M(UInt64, output_format_pretty_max_value_width_apply_for_single_value, false, "Only cut values (see the `output_format_pretty_max_value_width` setting) when it is not a single value in a block. Otherwise output it entirely, which is useful for the `SHOW CREATE TABLE` query.", 0) \
     M(UInt64Auto, output_format_pretty_color, "auto", "Use ANSI escape sequences in Pretty formats. 0 - disabled, 1 - enabled, 'auto' - enabled if a terminal.", 0) \
     M(String, output_format_pretty_grid_charset, "UTF-8", "Charset for printing grid borders. Available charsets: ASCII, UTF-8 (default one).", 0) \
     M(UInt64, output_format_parquet_row_group_size, 1000000, "Target row group size in rows.", 0) \

src/Core/SettingsChangesHistory.h

@@ -105,6 +105,7 @@ static std::map<ClickHouseVersion, SettingsChangesHistory::SettingsChanges> sett
               {"keeper_retry_max_backoff_ms", 5000, 5000, "Max backoff timeout for general keeper operations"},
               {"s3queue_allow_experimental_sharded_mode", false, false, "Enable experimental sharded mode of S3Queue table engine. It is experimental because it will be rewritten"},
               {"merge_tree_read_split_ranges_into_intersecting_and_non_intersecting_injection_probability", 0.0, 0.0, "For testing of `PartsSplitter` - split read ranges into intersecting and non intersecting every time you read from MergeTree with the specified probability."},
+              {"output_format_pretty_max_value_width_apply_for_single_value", true, false, "Single values in Pretty formats won't be cut."},
               {"output_format_parquet_string_as_string", false, true, "ClickHouse allows arbitrary binary data in the String data type, which is typically UTF-8. Parquet/ORC/Arrow Strings only support UTF-8. That's why you can choose which Arrow's data type to use for the ClickHouse String data type - String or Binary. While Binary would be more correct and compatible, using String by default will correspond to user expectations in most cases."},
               {"output_format_orc_string_as_string", false, true, "ClickHouse allows arbitrary binary data in the String data type, which is typically UTF-8. Parquet/ORC/Arrow Strings only support UTF-8. That's why you can choose which Arrow's data type to use for the ClickHouse String data type - String or Binary. While Binary would be more correct and compatible, using String by default will correspond to user expectations in most cases."},
               {"output_format_arrow_string_as_string", false, true, "ClickHouse allows arbitrary binary data in the String data type, which is typically UTF-8. Parquet/ORC/Arrow Strings only support UTF-8. That's why you can choose which Arrow's data type to use for the ClickHouse String data type - String or Binary. While Binary would be more correct and compatible, using String by default will correspond to user expectations in most cases."},

src/Formats/FormatFactory.cpp

@@ -167,6 +167,7 @@ FormatSettings getFormatSettings(const ContextPtr & context, const Settings & se
     format_settings.pretty.max_column_pad_width = settings.output_format_pretty_max_column_pad_width;
     format_settings.pretty.max_rows = settings.output_format_pretty_max_rows;
     format_settings.pretty.max_value_width = settings.output_format_pretty_max_value_width;
+    format_settings.pretty.max_value_width_apply_for_single_value = settings.output_format_pretty_max_value_width_apply_for_single_value;
     format_settings.pretty.highlight_digit_groups = settings.output_format_pretty_highlight_digit_groups;
     format_settings.pretty.output_format_pretty_row_numbers = settings.output_format_pretty_row_numbers;
     format_settings.pretty.output_format_pretty_single_large_number_tip_threshold = settings.output_format_pretty_single_large_number_tip_threshold;

src/Formats/FormatSettings.h

@@ -275,6 +275,7 @@ struct FormatSettings
         UInt64 max_rows = 10000;
         UInt64 max_column_pad_width = 250;
         UInt64 max_value_width = 10000;
+        UInt64 max_value_width_apply_for_single_value = false;
         bool highlight_digit_groups = true;
         SettingFieldUInt64Auto color{"auto"};
 

src/Processors/Formats/Impl/PrettyBlockOutputFormat.cpp

@@ -164,6 +164,10 @@ void PrettyBlockOutputFormat::writeChunk(const Chunk & chunk, PortKind port_kind
     const auto & columns = chunk.getColumns();
     const auto & header = getPort(port_kind).getHeader();
 
+    size_t cut_to_width = format_settings.pretty.max_value_width;
+    if (!format_settings.pretty.max_value_width_apply_for_single_value && num_rows == 1 && num_columns == 1 && total_rows == 0)
+        cut_to_width = 0;
+
     WidthsPerColumn widths;
     Widths max_widths;
     Widths name_widths;
@@ -303,7 +307,7 @@ void PrettyBlockOutputFormat::writeChunk(const Chunk & chunk, PortKind port_kind
             const auto & type = *header.getByPosition(j).type;
             writeValueWithPadding(*columns[j], *serializations[j], i,
                 widths[j].empty() ? max_widths[j] : widths[j][i],
-                max_widths[j], type.shouldAlignRightInPrettyFormats(), isNumber(type));
+                max_widths[j], cut_to_width, type.shouldAlignRightInPrettyFormats(), isNumber(type));
         }
 
         writeCString(grid_symbols.bar, out);
@@ -390,15 +394,15 @@ static String highlightDigitGroups(String source)
 
 void PrettyBlockOutputFormat::writeValueWithPadding(
     const IColumn & column, const ISerialization & serialization, size_t row_num,
-    size_t value_width, size_t pad_to_width, bool align_right, bool is_number)
+    size_t value_width, size_t pad_to_width, size_t cut_to_width, bool align_right, bool is_number)
 {
     String serialized_value = " ";
     {
         WriteBufferFromString out_serialize(serialized_value, AppendModeTag());
         serialization.serializeText(column, row_num, out_serialize, format_settings);
     }
 
-    if (value_width > format_settings.pretty.max_value_width)
+    if (cut_to_width && value_width > cut_to_width)
     {
         serialized_value.resize(UTF8::computeBytesBeforeWidth(
             reinterpret_cast<const UInt8 *>(serialized_value.data()), serialized_value.size(), 0, 1 + format_settings.pretty.max_value_width));

src/Processors/Formats/Impl/PrettyBlockOutputFormat.h

@@ -48,7 +48,7 @@ class PrettyBlockOutputFormat : public IOutputFormat
 
     void writeValueWithPadding(
         const IColumn & column, const ISerialization & serialization, size_t row_num,
-        size_t value_width, size_t pad_to_width, bool align_right, bool is_number);
+        size_t value_width, size_t pad_to_width, size_t cut_to_width, bool align_right, bool is_number);
 
     void resetFormatterImpl() override
     {

src/Processors/Formats/Impl/PrettyCompactBlockOutputFormat.cpp

@@ -160,6 +160,10 @@ void PrettyCompactBlockOutputFormat::writeRow(
     size_t num_columns = max_widths.size();
     const auto & columns = chunk.getColumns();
 
+    size_t cut_to_width = format_settings.pretty.max_value_width;
+    if (!format_settings.pretty.max_value_width_apply_for_single_value && chunk.getNumRows() == 1 && num_columns == 1 && total_rows == 0)
+        cut_to_width = 0;
+
     writeCString(grid_symbols.bar, out);
 
     for (size_t j = 0; j < num_columns; ++j)
@@ -169,7 +173,7 @@ void PrettyCompactBlockOutputFormat::writeRow(
 
         const auto & type = *header.getByPosition(j).type;
         const auto & cur_widths = widths[j].empty() ? max_widths[j] : widths[j][row_num];
-        writeValueWithPadding(*columns[j], *serializations[j], row_num, cur_widths, max_widths[j], type.shouldAlignRightInPrettyFormats(), isNumber(type));
+        writeValueWithPadding(*columns[j], *serializations[j], row_num, cur_widths, max_widths[j], cut_to_width, type.shouldAlignRightInPrettyFormats(), isNumber(type));
     }
 
     writeCString(grid_symbols.bar, out);

src/Processors/Formats/Impl/PrettySpaceBlockOutputFormat.cpp

@@ -24,6 +24,10 @@ void PrettySpaceBlockOutputFormat::writeChunk(const Chunk & chunk, PortKind port
     const auto & header = getPort(port_kind).getHeader();
     const auto & columns = chunk.getColumns();
 
+    size_t cut_to_width = format_settings.pretty.max_value_width;
+    if (!format_settings.pretty.max_value_width_apply_for_single_value && num_rows == 1 && num_columns == 1 && total_rows == 0)
+        cut_to_width = 0;
+
     WidthsPerColumn widths;
     Widths max_widths;
     Widths name_widths;
@@ -84,7 +88,7 @@ void PrettySpaceBlockOutputFormat::writeChunk(const Chunk & chunk, PortKind port
             const auto & type = *header.getByPosition(column).type;
             auto & cur_width = widths[column].empty() ? max_widths[column] : widths[column][row];
             writeValueWithPadding(
-                *columns[column], *serializations[column], row, cur_width, max_widths[column], type.shouldAlignRightInPrettyFormats(), isNumber(type));
+                *columns[column], *serializations[column], row, cur_width, max_widths[column], cut_to_width, type.shouldAlignRightInPrettyFormats(), isNumber(type));
         }
 
         writeReadableNumberTip(chunk);

tests/queries/0_stateless/01293_pretty_max_value_width.reference

@@ -84,31 +84,31 @@
 ┏━━━┳━━━┓
 ┃ x ┃ y ┃
 ┡━━━╇━━━┩
-│ ⋯ │ ⋯ │
+│ привет │ мир │
 └───┴───┘
 ┌─x─┬─y─┐
-│ ⋯ │ ⋯ │
+│ привет │ мир │
 └───┴───┘
  x   y
 
- ⋯   ⋯ 
+ привет   мир 
 ┏━━━┳━━━┓
 ┃ x ┃ y ┃
 ┡━━━╇━━━┩
-│ ⋯ │ ⋯ │
+│ привет │ мир │
 ├───┼───┤
-│ ⋯ │ ⋯ │
+│ мир │ привет │
 └───┴───┘
 ┌─x─┬─y─┐
-│ ⋯ │ ⋯ │
-│ ⋯ │ ⋯ │
+│ привет │ мир │
+│ мир │ привет │
 └───┴───┘
  x   y
 
- ⋯   ⋯ 
- ⋯   ⋯ 
+ привет   мир 
+ мир   привет 
 ┏━━━┳━━━┓
 ┃ x ┃ y ┃
 ┡━━━╇━━━┩
-│ ⋯ │ ⋯ │
+│ привет │ мир │
 └───┴───┘

tests/queries/0_stateless/01293_pretty_max_value_width.sql

@@ -1,4 +1,4 @@
-SET output_format_pretty_color=1;
+SET output_format_pretty_color = 1, output_format_pretty_max_value_width_apply_for_single_value = 1, output_format_pretty_row_numbers = 0;
 SELECT 'привет' AS x, 'мир' AS y FORMAT Pretty;
 
 SET output_format_pretty_max_value_width = 5;

tests/queries/0_stateless/03020_long_values_pretty_are_not_cut_if_single.reference

@@ -0,0 +1,4 @@
+COMMENT 'Contains history of metrics values from tables system.metrics and system.events, periodically flushed to disk.' │
+COMMENT 'Contains history of metrics values from tables system.metrics and system.events, periodically flushed to disk.' │
+COMMENT 'Contains history of metrics values from tables system.metrics and system.events, periodically flushed to disk.' 
+\nCOMMENT \'Contains history of metrics values from tables system.metrics and system.events, periodically flushed to disk.\'

tests/queries/0_stateless/03020_long_values_pretty_are_not_cut_if_single.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+CURDIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+# shellcheck source=../shell_config.sh
+. "$CURDIR"/../shell_config.sh
+
+# The metric_log table has a large number of columns, so its definition is also large.
+# And it is larger than the default value of `output_format_pretty_max_value_width`.
+# But cutting it in the result of SHOW CREATE TABLE will be bad for a user.
+# That's why we control it with the setting `output_format_pretty_max_value_width_apply_for_single_value`.
+
+${CLICKHOUSE_CLIENT} --query "SHOW CREATE TABLE system.metric_log" --format Pretty | grep -P '^COMMENT'
+${CLICKHOUSE_CLIENT} --query "SHOW CREATE TABLE system.metric_log" --format PrettyCompact | grep -P '^COMMENT'
+${CLICKHOUSE_CLIENT} --query "SHOW CREATE TABLE system.metric_log" --format PrettySpace | grep -P '^COMMENT'
+
+# Just in case, non-Pretty format:
+${CLICKHOUSE_CLIENT} --query "SHOW CREATE TABLE system.metric_log" --format TSV | grep -o -P '\\nCOMMENT.+$'