Clean up

src/Formats/EscapingRuleUtils.cpp

@@ -429,6 +429,7 @@ static DataTypePtr determineDataTypeForSingleFieldImpl(ReadBuffer & buf)
     if (checkStringCaseInsensitive("NULL", buf))
         return std::make_shared<DataTypeNothing>();
 
+    /// Number
     Float64 tmp;
     if (tryReadFloatText(tmp, buf))
         return std::make_shared<DataTypeFloat64>();

src/Formats/EscapingRuleUtils.h

@@ -43,12 +43,17 @@ String readFieldByEscapingRule(ReadBuffer & buf, FormatSettings::EscapingRule es
 /// - For JSON escaping rule we can use JSON parser to parse a single field
 ///   and then convert JSON type of this field to ClickHouse type.
 /// - For CSV escaping rule we can do the next:
-///    - If the field is an unquoted string, then we could try to evaluate it
+///    - If the field is an unquoted string, then we try to parse it as s number,
-///      as a constant expression, and if it fails, treat it as a String.
+///      and if we cannot, treat it as a String.
-///    - If the field is a string in quotes, then we can try to evaluate
+///    - If the field is a string in quotes, then we try to use some
-///      expression inside quotes as a constant expression, and if it fails or
+///      tweaks and heuristics to determine the type inside quotes, and if we can't or
-///      the result is a number (we don't parse numbers in quotes) we treat it as a String.
+///      the result is a number or tuple (we don't parse numbers in quotes and don't
-/// - For TSV and TSVRaw we treat each field as a String (TODO: try to use some tweaks and heuristics here)
+///      support tuples in CSV) we treat it as a String.
+///    - If input_format_csv_use_best_effort_in_schema_inference is disabled, we
+///      treat everything as a string.
+/// - For TSV and TSVRaw we try to use some tweaks and heuristics to determine the type
+///   of value if setting input_format_tsv_use_best_effort_in_schema_inference is enabled,
+///   otherwise we treat everything as a string.
 DataTypePtr determineDataTypeByEscapingRule(const String & field, const FormatSettings & format_settings, FormatSettings::EscapingRule escaping_rule);
 DataTypes determineDataTypesByEscapingRule(const std::vector<String> & fields, const FormatSettings & format_settings, FormatSettings::EscapingRule escaping_rule);
 

src/Formats/FormatSettings.h

@@ -112,7 +112,7 @@ struct FormatSettings
         char fields_delimiter = '\x01';
         char collection_items_delimiter = '\x02';
         char map_keys_delimiter = '\x03';
-        Names input_field_names = {""};
+        Names input_field_names;
     } hive_text;
 
     struct Custom