# https://docs.snowflake.com/en/sql-reference/identifiers-syntax

NORMALIZATION_STRATEGY = NormalizationStrategy.UPPERCASE

# https://docs.snowflake.com/en/sql-reference/data-types-text#escape-sequences

UNESCAPED_SEQUENCES = {"\\a": "a", "\\v": "v"}

NULL_ORDERING = "nulls_are_large"

TIME_FORMAT = "'YYYY-MM-DD HH24:MI:SS'"

SUPPORTS_USER_DEFINED_TYPES = False

PREFER_CTE_ALIAS_COLUMN = True

SUPPORTS_POSITIONAL_COLUMN_REFS = True

TABLESAMPLE_SIZE_IS_PERCENT = True

COPY_PARAMS_ARE_CSV = False

ARRAY_AGG_INCLUDES_NULLS = None

ARRAY_FUNCS_PROPAGATES_NULLS = True

ALTER_TABLE_ADD_REQUIRED_FOR_EACH_COLUMN = False

ALTER_TABLE_DROP_REQUIRED_FOR_EACH_COLUMN = False

TRY_CAST_REQUIRES_STRING = True

SUPPORTS_ALIAS_REFS_IN_JOIN_CONDITIONS = True

LEAST_GREATEST_IGNORES_NULLS = False

UUID_IS_STRING_TYPE = True

STAR_ILIKE_BACKSLASH_ESCAPE = True

# https://docs.snowflake.com/en/sql-reference/functions/split_to_table

DEFAULT_FUNCTIONS_COLUMN_NAMES = {

exp.SplitToTable: ("seq", "index", "value"),

exp.StrtokSplitToTable: ("seq", "index", "value"),

}

EXPRESSION_METADATA = EXPRESSION_METADATA.copy()

# https://docs.snowflake.com/en/en/sql-reference/functions/initcap

INITCAP_DEFAULT_DELIMITER_CHARS = ' \t\n\r\f\v!?@"^#$&~_,.:;+\\-*%/|\\[\\](){}<>'

INVERSE_TIME_MAPPING = {

"T": "T", # in TIME_MAPPING we map '"T"' with the double quotes to 'T', and we want to prevent 'T' from being mapped back to '"T"' so that 'AUTO' doesn't become 'AU"T"O'

}

TIME_MAPPING = {

"YYYY": "%Y",

"yyyy": "%Y",

"YY": "%y",

"yy": "%y",

"MMMM": "%B",

"mmmm": "%B",

"MON": "%b",

"mon": "%b",

"MM": "%m",

"mm": "%m",

"DD": "%d",

"dd": "%-d",

"DY": "%a",

"dy": "%w",

"HH24": "%H",

"hh24": "%H",

"HH12": "%I",

"hh12": "%I",

"MI": "%M",

"mi": "%M",

"SS": "%S",

"ss": "%S",

"FF": "%f_nine", # %f_ internal representation with precision specified

"ff": "%f_nine",

"FF0": "%f_zero",

"ff0": "%f_zero",

"FF1": "%f_one",

"ff1": "%f_one",

"FF2": "%f_two",

"ff2": "%f_two",

"FF3": "%f_three",

"ff3": "%f_three",

"FF4": "%f_four",

"ff4": "%f_four",

"FF5": "%f_five",

"ff5": "%f_five",

"FF6": "%f",

"ff6": "%f",

"FF7": "%f_seven",

"ff7": "%f_seven",

"FF8": "%f_eight",

"ff8": "%f_eight",

"FF9": "%f_nine",

"ff9": "%f_nine",

"TZHTZM": "%z",

"tzhtzm": "%z",

"TZH:TZM": "%:z", # internal representation for ±HH:MM

"tzh:tzm": "%:z",

"TZH": "%-z", # internal representation ±HH

"tzh": "%-z",

'"T"': "T", # remove the optional double quotes around the separator between the date and time

# Seems like Snowflake treats AM/PM in the format string as equivalent,

# only the time (stamp) value's AM/PM affects the output

"AM": "%p",

"am": "%p",

"PM": "%p",

"pm": "%p",

}

DATE_PART_MAPPING = {

**Dialect.DATE_PART_MAPPING,

"ISOWEEK": "WEEKISO",

# The base Dialect maps EPOCH_SECOND -> EPOCH, but we need to preserve

# EPOCH_SECOND as a distinct value for two reasons:

# 1. Type annotation: EPOCH_SECOND returns BIGINT, while EPOCH returns DOUBLE

# 2. Transpilation: DuckDB's EPOCH() returns float, so we cast EPOCH_SECOND

# to BIGINT to match Snowflake's integer behavior

# Without this override, EXTRACT(EPOCH_SECOND FROM ts) would be normalized

# to EXTRACT(EPOCH FROM ts) and lose the integer semantics.

"EPOCH_SECOND": "EPOCH_SECOND",

"EPOCH_SECONDS": "EPOCH_SECOND",

}

PSEUDOCOLUMNS = {"LEVEL"}

def can_quote(self, identifier: exp.Identifier, identify: str | bool = "safe") -> bool:

# This disables quoting DUAL in SELECT ... FROM DUAL, because Snowflake treats an

# unquoted DUAL keyword in a special way and does not map it to a user-defined table

return super().can_quote(identifier, identify) and not (

isinstance(identifier.parent, exp.Table)

and not identifier.quoted

and identifier.name.lower() == "dual"

)

class JSONPathTokenizer(jsonpath.JSONPathTokenizer):

SINGLE_TOKENS = jsonpath.JSONPathTokenizer.SINGLE_TOKENS.copy()

SINGLE_TOKENS.pop("$")

Parser = SnowflakeParser

class Tokenizer(tokens.Tokenizer):

STRING_ESCAPES = ["\\", "'"]

NUMERIC_ESCAPES = {"x": (16, 2, 2, 0xFF), "u": (16, 4, 4, 0xFFFF), "0": (8, 1, 3, 0xFF)}

DROP_UNKNOWN_ESCAPES = True

HEX_STRINGS = [("x'", "'"), ("X'", "'")]

RAW_STRINGS = ["$$"]

COMMENTS = ["--", "//", ("/*", "*/")]

NESTED_COMMENTS = False

KEYWORDS = {

**tokens.Tokenizer.KEYWORDS,

"(+)": TokenType.JOIN_MARKER,

"BYTEINT": TokenType.INT,

"FILE://": TokenType.URI_START,

"FILE FORMAT": TokenType.FILE_FORMAT,

"GET": TokenType.GET,

"INTEGRATION": TokenType.INTEGRATION,

"LS": TokenType.LIST,

"MATCH_CONDITION": TokenType.MATCH_CONDITION,

"MATCH_RECOGNIZE": TokenType.MATCH_RECOGNIZE,

"MINUS": TokenType.EXCEPT,

"NCHAR VARYING": TokenType.VARCHAR,

"PACKAGE": TokenType.PACKAGE,

"POLICY": TokenType.POLICY,

"POOL": TokenType.POOL,

"PUT": TokenType.PUT,

"UNDROP": TokenType.UNDROP,

"REMOVE": TokenType.COMMAND,

"RM": TokenType.COMMAND,

"ROLE": TokenType.ROLE,

"RULE": TokenType.RULE,

"SAMPLE": TokenType.TABLE_SAMPLE,

"SEMANTIC VIEW": TokenType.SEMANTIC_VIEW,

"SQL_DOUBLE": TokenType.DOUBLE,

"SQL_VARCHAR": TokenType.VARCHAR,

"STAGE": TokenType.STAGE,

"STORAGE INTEGRATION": TokenType.STORAGE_INTEGRATION,

"STREAMLIT": TokenType.STREAMLIT,

"TAG": TokenType.TAG,

"TIMESTAMP_TZ": TokenType.TIMESTAMPTZ,

"TOP": TokenType.TOP,

"VOLUME": TokenType.VOLUME,

"WAREHOUSE": TokenType.WAREHOUSE,

# https://docs.snowflake.com/en/sql-reference/data-types-numeric#float

# FLOAT is a synonym for DOUBLE in Snowflake

"FLOAT": TokenType.DOUBLE,

}

KEYWORDS.pop("/*+")

SINGLE_TOKENS = {

**tokens.Tokenizer.SINGLE_TOKENS,

"$": TokenType.PARAMETER,

"!": TokenType.EXCLAMATION,

}

VAR_SINGLE_TOKENS = {"$"}

COMMANDS = tokens.Tokenizer.COMMANDS - {TokenType.SHOW}