Struct GeneratorConfig 

pub struct GeneratorConfig {

    pub pretty: bool,
    pub indent: String,
    pub max_text_width: usize,
    pub identifier_quote: char,
    pub identifier_quote_style: IdentifierQuoteStyle,
    pub uppercase_keywords: bool,
    pub normalize_identifiers: bool,
    pub dialect: Option<DialectType>,
    pub normalize_functions: NormalizeFunctions,
    pub string_escape: char,
    pub case_sensitive_identifiers: bool,
    pub identifiers_can_start_with_digit: bool,
    pub always_quote_identifiers: bool,
    pub null_ordering_supported: bool,
    pub ignore_nulls_in_func: bool,
    pub nvl2_supported: bool,
    pub limit_fetch_style: LimitFetchStyle,
    pub limit_is_top: bool,
    pub limit_only_literals: bool,
    pub single_string_interval: bool,
    pub interval_allows_plural_form: bool,
    pub cte_recursive_keyword_required: bool,
    pub values_as_table: bool,
    pub wrap_derived_values: bool,
    pub tablesample_seed_keyword: &'static str,
    pub tablesample_requires_parens: bool,
    pub tablesample_size_is_rows: bool,
    pub tablesample_keywords: &'static str,
    pub tablesample_with_method: bool,
    pub alias_post_tablesample: bool,
    pub aggregate_filter_supported: bool,
    pub multi_arg_distinct: bool,
    pub quantified_no_paren_space: bool,
    pub supports_median: bool,
    pub supports_select_into: bool,
    pub locking_reads_supported: bool,
    pub rename_table_with_db: bool,
    pub semi_anti_join_with_side: bool,
    pub supports_table_alias_columns: bool,
    pub join_hints: bool,
    pub table_hints: bool,
    pub query_hints: bool,
    pub query_hint_sep: &'static str,
    pub supports_column_join_marks: bool,
    pub index_using_no_space: bool,
    pub supports_unlogged_tables: bool,
    pub supports_create_table_like: bool,
    pub like_property_inside_schema: bool,
    pub alter_table_include_column_keyword: bool,
    pub supports_table_copy: bool,
    pub alter_set_type: &'static str,
    pub alter_set_wrapped: bool,
    pub tz_to_with_time_zone: bool,
    pub supports_convert_timezone: bool,
    pub json_type_required_for_extraction: bool,
    pub json_path_bracketed_key_supported: bool,
    pub json_path_single_quote_escape: bool,
    pub quote_json_path: bool,
    pub json_key_value_pair_sep: &'static str,
    pub copy_params_are_wrapped: bool,
    pub copy_params_eq_required: bool,
    pub copy_has_into_keyword: bool,
    pub supports_window_exclude: bool,
    pub unnest_with_ordinality: bool,
    pub lowercase_window_frame_keywords: bool,
    pub normalize_window_frame_between: bool,
    pub array_concat_is_var_len: bool,
    pub array_size_dim_required: Option<bool>,
    pub can_implement_array_any: bool,
    pub array_size_name: &'static str,
    pub supports_between_flags: bool,
    pub is_bool_allowed: bool,
    pub ensure_bools: bool,
    pub extract_allows_quotes: bool,
    pub normalize_extract_date_parts: bool,
    pub try_supported: bool,
    pub supports_uescape: bool,
    pub supports_to_number: bool,
    pub supports_single_arg_concat: bool,
    pub last_day_supports_date_part: bool,
    pub supports_exploding_projections: bool,
    pub supports_unix_seconds: bool,
    pub supports_like_quantifiers: bool,
    pub supports_decode_case: bool,
    pub set_op_modifiers: bool,
    pub update_statement_supports_from: bool,
    pub collate_is_func: bool,
    pub duplicate_key_update_with_set: bool,
    pub insert_overwrite: &'static str,
    pub returning_end: bool,
    pub matched_by_source: bool,
    pub create_function_return_as: bool,
    pub parameter_default_equals: bool,
    pub computed_column_with_type: bool,
    pub unpivot_aliases_are_identifiers: bool,
    pub star_except: &'static str,
    pub hex_func: &'static str,
    pub with_properties_prefix: &'static str,
    pub pad_fill_pattern_is_required: bool,
    pub index_on: &'static str,
    pub groupings_sep: &'static str,
    pub struct_delimiter: (&'static str, &'static str),
    pub struct_curly_brace_notation: bool,
    pub array_bracket_only: bool,
    pub struct_field_sep: &'static str,
    pub except_intersect_support_all_clause: bool,
    pub parameter_token: &'static str,
    pub named_placeholder_token: &'static str,
    pub data_type_specifiers_allowed: bool,
    pub schema_comment_with_eq: bool,
}

Configuration for the SQL Generator.

This is a comprehensive port of the Python sqlglot Generator class attributes. It controls every aspect of SQL output: formatting, quoting, dialect-specific syntax, feature support flags, and more.

Most users should start from GeneratorConfig::default() and override only the fields they need. Dialect-specific presets are applied automatically when dialect is set via the higher-level transpilation API.

Key fields

Field	Default	Purpose
dialect	None	Target SQL dialect (e.g. PostgreSQL, MySQL, BigQuery)
pretty	false	Enable multi-line, indented output
indent	" "	Indentation string used when pretty is true
max_text_width	80	Soft line-width limit for pretty-printing
normalize_functions	Upper	Function name casing (Upper, Lower, None)
identifier_quote_style	"…"	Quote characters for identifiers
uppercase_keywords	true	Whether SQL keywords are upper-cased

Fields

pretty: bool

Pretty print with indentation

indent: String

Indentation string (default 2 spaces)

max_text_width: usize

Maximum text width before wrapping (default 80)

identifier_quote: char

Quote identifier style (deprecated, use identifier_quote_style instead)

identifier_quote_style: IdentifierQuoteStyle

Identifier quote style with separate start/end characters

uppercase_keywords: bool

Uppercase keywords

normalize_identifiers: bool

Normalize identifiers to lowercase when generating

dialect: Option<DialectType>

Dialect type for dialect-specific generation

normalize_functions: NormalizeFunctions

How to output function names (UPPER, lower, or as-is)

string_escape: char

String escape character

case_sensitive_identifiers: bool

Whether identifiers are case-sensitive

identifiers_can_start_with_digit: bool

Whether unquoted identifiers can start with a digit

always_quote_identifiers: bool

Whether to always quote identifiers regardless of reserved keyword status Used by dialects like Athena/Presto that prefer quoted identifiers

null_ordering_supported: bool

Whether null ordering (NULLS FIRST/LAST) is supported in ORDER BY True: Full Support, false: No support

ignore_nulls_in_func: bool

Whether ignore nulls is inside the agg or outside FIRST(x IGNORE NULLS) OVER vs FIRST(x) IGNORE NULLS OVER

nvl2_supported: bool

Whether the NVL2 function is supported

limit_fetch_style: LimitFetchStyle

How to output LIMIT clauses

limit_is_top: bool

Whether to generate the limit as TOP instead of LIMIT

limit_only_literals: bool

Whether limit and fetch allows expressions or just literals

single_string_interval: bool

Whether INTERVAL uses single quoted string (‘1 day’ vs 1 DAY)

interval_allows_plural_form: bool

Whether the plural form of date parts (e.g., “days”) is supported in INTERVALs

cte_recursive_keyword_required: bool

Whether WITH RECURSIVE keyword is required (vs just WITH for recursive CTEs)

values_as_table: bool

Whether VALUES can be used as a table source

wrap_derived_values: bool

Wrap derived values in parens (standard but Spark doesn’t support)

tablesample_seed_keyword: &'static str

Keyword for TABLESAMPLE seed: “SEED” or “REPEATABLE”

tablesample_requires_parens: bool

Whether parentheses are required around the table sample’s expression

tablesample_size_is_rows: bool

Whether a table sample clause’s size needs to be followed by ROWS keyword

tablesample_keywords: &'static str

The keyword(s) to use when generating a sample clause

tablesample_with_method: bool

Whether the TABLESAMPLE clause supports a method name, like BERNOULLI

alias_post_tablesample: bool

Whether the table alias comes after tablesample (Oracle, Hive)

aggregate_filter_supported: bool

Whether aggregate FILTER (WHERE …) is supported

multi_arg_distinct: bool

Whether DISTINCT can be followed by multiple args in an AggFunc

quantified_no_paren_space: bool

Whether ANY/ALL quantifiers have no space before (: ANY( vs ANY (

supports_median: bool

Whether MEDIAN(expr) is supported; if not, generates PERCENTILE_CONT

supports_select_into: bool

Whether SELECT … INTO is supported

locking_reads_supported: bool

Whether locking reads (SELECT … FOR UPDATE/SHARE) are supported

rename_table_with_db: bool

Whether a table is allowed to be renamed with a db

semi_anti_join_with_side: bool

Whether JOIN sides (LEFT, RIGHT) are supported with SEMI/ANTI join kinds

supports_table_alias_columns: bool

Whether named columns are allowed in table aliases

join_hints: bool

Whether join hints should be generated

table_hints: bool

Whether table hints should be generated

query_hints: bool

Whether query hints should be generated

query_hint_sep: &'static str

What kind of separator to use for query hints

supports_column_join_marks: bool

Whether Oracle-style (+) join markers are supported (Oracle, Exasol)

index_using_no_space: bool

Whether CREATE INDEX USING method should have no space before column parens true: USING btree(col), false: USING btree (col)

supports_unlogged_tables: bool

Whether UNLOGGED tables can be created

supports_create_table_like: bool

Whether CREATE TABLE LIKE statement is supported

like_property_inside_schema: bool

Whether the LikeProperty needs to be inside the schema clause

alter_table_include_column_keyword: bool

Whether the word COLUMN is included when adding a column with ALTER TABLE

supports_table_copy: bool

Whether CREATE TABLE .. COPY .. is supported (false = CLONE instead)

alter_set_type: &'static str

The syntax to use when altering the type of a column

alter_set_wrapped: bool

Whether to wrap in AlterSet, e.g., ALTER … SET ()

tz_to_with_time_zone: bool

Whether TIMESTAMP WITH TIME ZONE is used (vs TIMESTAMPTZ)

supports_convert_timezone: bool

Whether CONVERT_TIMEZONE() is supported

json_type_required_for_extraction: bool

Whether the JSON extraction operators expect a value of type JSON

json_path_bracketed_key_supported: bool

Whether bracketed keys like [“foo”] are supported in JSON paths

json_path_single_quote_escape: bool

Whether to escape keys using single quotes in JSON paths

quote_json_path: bool

Whether to quote the generated expression of JsonPath

json_key_value_pair_sep: &'static str

What delimiter to use for separating JSON key/value pairs

copy_params_are_wrapped: bool

Whether parameters from COPY statement are wrapped in parentheses

copy_params_eq_required: bool

Whether values of params are set with “=” token or empty space

copy_has_into_keyword: bool

Whether COPY statement has INTO keyword

supports_window_exclude: bool

Whether EXCLUDE in window specification is supported

unnest_with_ordinality: bool

UNNEST WITH ORDINALITY (presto) instead of UNNEST WITH OFFSET (bigquery)

lowercase_window_frame_keywords: bool

Whether window frame keywords (ROWS/RANGE/GROUPS, PRECEDING/FOLLOWING) should be lowercase Exasol uses lowercase for these specific keywords

normalize_window_frame_between: bool

Whether to normalize single-bound window frames to BETWEEN form e.g., ROWS 1 PRECEDING → ROWS BETWEEN 1 PRECEDING AND CURRENT ROW

array_concat_is_var_len: bool

Whether ARRAY_CONCAT can be generated with varlen args

array_size_dim_required: Option<bool>

Whether exp.ArraySize should generate the dimension arg too None -> Doesn’t support, false -> optional, true -> required

can_implement_array_any: bool

Whether any(f(x) for x in array) can be implemented

array_size_name: &'static str

Function used for array size

supports_between_flags: bool

Whether SYMMETRIC and ASYMMETRIC flags are supported with BETWEEN

is_bool_allowed: bool

Whether comparing against booleans (e.g. x IS TRUE) is supported

ensure_bools: bool

Whether conditions require booleans WHERE x = 0 vs WHERE x

extract_allows_quotes: bool

Whether to generate an unquoted value for EXTRACT’s date part argument

normalize_extract_date_parts: bool

Whether to normalize date parts in EXTRACT

try_supported: bool

Whether the conditional TRY(expression) function is supported

supports_uescape: bool

Whether the UESCAPE syntax in unicode strings is supported

supports_to_number: bool

Whether the function TO_NUMBER is supported

supports_single_arg_concat: bool

Whether CONCAT requires >1 arguments

last_day_supports_date_part: bool

Whether LAST_DAY function supports a date part argument

supports_exploding_projections: bool

Whether a projection can explode into multiple rows

supports_unix_seconds: bool

Whether UNIX_SECONDS(timestamp) is supported

supports_like_quantifiers: bool

Whether LIKE and ILIKE support quantifiers such as LIKE ANY/ALL/SOME

supports_decode_case: bool

Whether multi-argument DECODE(…) function is supported

set_op_modifiers: bool

Whether set op modifiers apply to the outer set op or select

update_statement_supports_from: bool

Whether FROM is supported in UPDATE statements

collate_is_func: bool

Whether COLLATE is a function instead of a binary operator

duplicate_key_update_with_set: bool

Whether to include “SET” keyword in “INSERT … ON DUPLICATE KEY UPDATE”

insert_overwrite: &'static str

INSERT OVERWRITE TABLE x override

returning_end: bool

Whether to generate INSERT INTO … RETURNING or INSERT INTO RETURNING …

matched_by_source: bool

Whether MERGE … WHEN MATCHED BY SOURCE is allowed

create_function_return_as: bool

Whether create function uses an AS before the RETURN

parameter_default_equals: bool

Whether to use = instead of DEFAULT for parameter defaults (TSQL style)

computed_column_with_type: bool

Whether to include the type of a computed column in the CREATE DDL

unpivot_aliases_are_identifiers: bool

Whether UNPIVOT aliases are Identifiers (false means they’re Literals)

star_except: &'static str

The keyword to use when generating a star projection with excluded columns

hex_func: &'static str

The HEX function name

with_properties_prefix: &'static str

The keywords to use when prefixing WITH based properties

pad_fill_pattern_is_required: bool

Whether the text pattern/fill (3rd) parameter of RPAD()/LPAD() is optional

index_on: &'static str

The string used for creating an index on a table

groupings_sep: &'static str

The separator for grouping sets and rollups

struct_delimiter: (&'static str, &'static str)

Delimiters for STRUCT type

struct_curly_brace_notation: bool

Whether Struct expressions use curly brace notation: {‘key’: value} (DuckDB)

array_bracket_only: bool

Whether Array expressions omit the ARRAY keyword: [1, 2] instead of ARRAY[1, 2]

struct_field_sep: &'static str

Separator between struct field name and type (“: “ for Hive, “ “ for others)

except_intersect_support_all_clause: bool

Whether EXCEPT and INTERSECT operations can return duplicates

parameter_token: &'static str

Parameter token character (@ for TSQL, $ for PostgreSQL)

named_placeholder_token: &'static str

Named placeholder token (: for most, % for PostgreSQL)

data_type_specifiers_allowed: bool

Whether data types support additional specifiers like CHAR or BYTE (oracle)

schema_comment_with_eq: bool

Whether schema comments use = sign (COMMENT=‘value’ vs COMMENT ‘value’) StarRocks and Doris use naked COMMENT syntax without =

Trait Implementations

impl Clone for GeneratorConfig

fn clone(&self) -> GeneratorConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GeneratorConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for GeneratorConfig

fn default() -> Self

Returns the “default value” for a type.