sqlglot.dialects.snowflake
1from __future__ import annotations 2 3from sqlglot import exp, jsonpath, tokens 4from sqlglot.dialects.dialect import ( 5 Dialect, 6 NormalizationStrategy, 7) 8from sqlglot.generators.snowflake import SnowflakeGenerator 9from sqlglot.parsers.snowflake import ( 10 SnowflakeParser, 11) 12from sqlglot.tokens import TokenType 13from sqlglot.typing.snowflake import EXPRESSION_METADATA 14 15 16class Snowflake(Dialect): 17 # https://docs.snowflake.com/en/sql-reference/identifiers-syntax 18 NORMALIZATION_STRATEGY = NormalizationStrategy.UPPERCASE 19 # https://docs.snowflake.com/en/sql-reference/data-types-text#escape-sequences 20 UNESCAPED_SEQUENCES = {"\\a": "a", "\\v": "v"} 21 NULL_ORDERING = "nulls_are_large" 22 TIME_FORMAT = "'YYYY-MM-DD HH24:MI:SS'" 23 SUPPORTS_USER_DEFINED_TYPES = False 24 PREFER_CTE_ALIAS_COLUMN = True 25 TABLESAMPLE_SIZE_IS_PERCENT = True 26 COPY_PARAMS_ARE_CSV = False 27 ARRAY_AGG_INCLUDES_NULLS = None 28 ARRAY_FUNCS_PROPAGATES_NULLS = True 29 ALTER_TABLE_ADD_REQUIRED_FOR_EACH_COLUMN = False 30 TRY_CAST_REQUIRES_STRING = True 31 SUPPORTS_ALIAS_REFS_IN_JOIN_CONDITIONS = True 32 LEAST_GREATEST_IGNORES_NULLS = False 33 UUID_IS_STRING_TYPE = True 34 35 EXPRESSION_METADATA = EXPRESSION_METADATA.copy() 36 37 # https://docs.snowflake.com/en/en/sql-reference/functions/initcap 38 INITCAP_DEFAULT_DELIMITER_CHARS = ' \t\n\r\f\v!?@"^#$&~_,.:;+\\-*%/|\\[\\](){}<>' 39 40 INVERSE_TIME_MAPPING = { 41 "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' 42 } 43 44 TIME_MAPPING = { 45 "YYYY": "%Y", 46 "yyyy": "%Y", 47 "YY": "%y", 48 "yy": "%y", 49 "MMMM": "%B", 50 "mmmm": "%B", 51 "MON": "%b", 52 "mon": "%b", 53 "MM": "%m", 54 "mm": "%m", 55 "DD": "%d", 56 "dd": "%-d", 57 "DY": "%a", 58 "dy": "%w", 59 "HH24": "%H", 60 "hh24": "%H", 61 "HH12": "%I", 62 "hh12": "%I", 63 "MI": "%M", 64 "mi": "%M", 65 "SS": "%S", 66 "ss": "%S", 67 "FF": "%f_nine", # %f_ internal representation with precision specified 68 "ff": "%f_nine", 69 "FF0": "%f_zero", 70 "ff0": "%f_zero", 71 "FF1": "%f_one", 72 "ff1": "%f_one", 73 "FF2": "%f_two", 74 "ff2": "%f_two", 75 "FF3": "%f_three", 76 "ff3": "%f_three", 77 "FF4": "%f_four", 78 "ff4": "%f_four", 79 "FF5": "%f_five", 80 "ff5": "%f_five", 81 "FF6": "%f", 82 "ff6": "%f", 83 "FF7": "%f_seven", 84 "ff7": "%f_seven", 85 "FF8": "%f_eight", 86 "ff8": "%f_eight", 87 "FF9": "%f_nine", 88 "ff9": "%f_nine", 89 "TZHTZM": "%z", 90 "tzhtzm": "%z", 91 "TZH:TZM": "%:z", # internal representation for ±HH:MM 92 "tzh:tzm": "%:z", 93 "TZH": "%-z", # internal representation ±HH 94 "tzh": "%-z", 95 '"T"': "T", # remove the optional double quotes around the separator between the date and time 96 # Seems like Snowflake treats AM/PM in the format string as equivalent, 97 # only the time (stamp) value's AM/PM affects the output 98 "AM": "%p", 99 "am": "%p", 100 "PM": "%p", 101 "pm": "%p", 102 } 103 104 DATE_PART_MAPPING = { 105 **Dialect.DATE_PART_MAPPING, 106 "ISOWEEK": "WEEKISO", 107 # The base Dialect maps EPOCH_SECOND -> EPOCH, but we need to preserve 108 # EPOCH_SECOND as a distinct value for two reasons: 109 # 1. Type annotation: EPOCH_SECOND returns BIGINT, while EPOCH returns DOUBLE 110 # 2. Transpilation: DuckDB's EPOCH() returns float, so we cast EPOCH_SECOND 111 # to BIGINT to match Snowflake's integer behavior 112 # Without this override, EXTRACT(EPOCH_SECOND FROM ts) would be normalized 113 # to EXTRACT(EPOCH FROM ts) and lose the integer semantics. 114 "EPOCH_SECOND": "EPOCH_SECOND", 115 "EPOCH_SECONDS": "EPOCH_SECOND", 116 } 117 118 PSEUDOCOLUMNS = {"LEVEL"} 119 120 def can_quote(self, identifier: exp.Identifier, identify: str | bool = "safe") -> bool: 121 # This disables quoting DUAL in SELECT ... FROM DUAL, because Snowflake treats an 122 # unquoted DUAL keyword in a special way and does not map it to a user-defined table 123 return super().can_quote(identifier, identify) and not ( 124 isinstance(identifier.parent, exp.Table) 125 and not identifier.quoted 126 and identifier.name.lower() == "dual" 127 ) 128 129 class JSONPathTokenizer(jsonpath.JSONPathTokenizer): 130 SINGLE_TOKENS = jsonpath.JSONPathTokenizer.SINGLE_TOKENS.copy() 131 SINGLE_TOKENS.pop("$") 132 133 Parser = SnowflakeParser 134 135 class Tokenizer(tokens.Tokenizer): 136 STRING_ESCAPES = ["\\", "'"] 137 HEX_STRINGS = [("x'", "'"), ("X'", "'")] 138 RAW_STRINGS = ["$$"] 139 COMMENTS = ["--", "//", ("/*", "*/")] 140 NESTED_COMMENTS = False 141 142 KEYWORDS = { 143 **tokens.Tokenizer.KEYWORDS, 144 "BYTEINT": TokenType.INT, 145 "FILE://": TokenType.URI_START, 146 "FILE FORMAT": TokenType.FILE_FORMAT, 147 "GET": TokenType.GET, 148 "INTEGRATION": TokenType.INTEGRATION, 149 "MATCH_CONDITION": TokenType.MATCH_CONDITION, 150 "MATCH_RECOGNIZE": TokenType.MATCH_RECOGNIZE, 151 "MINUS": TokenType.EXCEPT, 152 "NCHAR VARYING": TokenType.VARCHAR, 153 "PACKAGE": TokenType.PACKAGE, 154 "POLICY": TokenType.POLICY, 155 "POOL": TokenType.POOL, 156 "PUT": TokenType.PUT, 157 "UNDROP": TokenType.UNDROP, 158 "REMOVE": TokenType.COMMAND, 159 "RM": TokenType.COMMAND, 160 "ROLE": TokenType.ROLE, 161 "RULE": TokenType.RULE, 162 "SAMPLE": TokenType.TABLE_SAMPLE, 163 "SEMANTIC VIEW": TokenType.SEMANTIC_VIEW, 164 "SQL_DOUBLE": TokenType.DOUBLE, 165 "SQL_VARCHAR": TokenType.VARCHAR, 166 "STAGE": TokenType.STAGE, 167 "STORAGE INTEGRATION": TokenType.STORAGE_INTEGRATION, 168 "STREAMLIT": TokenType.STREAMLIT, 169 "TAG": TokenType.TAG, 170 "TIMESTAMP_TZ": TokenType.TIMESTAMPTZ, 171 "TOP": TokenType.TOP, 172 "VOLUME": TokenType.VOLUME, 173 "WAREHOUSE": TokenType.WAREHOUSE, 174 # https://docs.snowflake.com/en/sql-reference/data-types-numeric#float 175 # FLOAT is a synonym for DOUBLE in Snowflake 176 "FLOAT": TokenType.DOUBLE, 177 } 178 KEYWORDS.pop("/*+") 179 180 SINGLE_TOKENS = { 181 **tokens.Tokenizer.SINGLE_TOKENS, 182 "$": TokenType.PARAMETER, 183 "!": TokenType.EXCLAMATION, 184 } 185 186 VAR_SINGLE_TOKENS = {"$"} 187 188 COMMANDS = tokens.Tokenizer.COMMANDS - {TokenType.SHOW} 189 190 Generator = SnowflakeGenerator
17class Snowflake(Dialect): 18 # https://docs.snowflake.com/en/sql-reference/identifiers-syntax 19 NORMALIZATION_STRATEGY = NormalizationStrategy.UPPERCASE 20 # https://docs.snowflake.com/en/sql-reference/data-types-text#escape-sequences 21 UNESCAPED_SEQUENCES = {"\\a": "a", "\\v": "v"} 22 NULL_ORDERING = "nulls_are_large" 23 TIME_FORMAT = "'YYYY-MM-DD HH24:MI:SS'" 24 SUPPORTS_USER_DEFINED_TYPES = False 25 PREFER_CTE_ALIAS_COLUMN = True 26 TABLESAMPLE_SIZE_IS_PERCENT = True 27 COPY_PARAMS_ARE_CSV = False 28 ARRAY_AGG_INCLUDES_NULLS = None 29 ARRAY_FUNCS_PROPAGATES_NULLS = True 30 ALTER_TABLE_ADD_REQUIRED_FOR_EACH_COLUMN = False 31 TRY_CAST_REQUIRES_STRING = True 32 SUPPORTS_ALIAS_REFS_IN_JOIN_CONDITIONS = True 33 LEAST_GREATEST_IGNORES_NULLS = False 34 UUID_IS_STRING_TYPE = True 35 36 EXPRESSION_METADATA = EXPRESSION_METADATA.copy() 37 38 # https://docs.snowflake.com/en/en/sql-reference/functions/initcap 39 INITCAP_DEFAULT_DELIMITER_CHARS = ' \t\n\r\f\v!?@"^#$&~_,.:;+\\-*%/|\\[\\](){}<>' 40 41 INVERSE_TIME_MAPPING = { 42 "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' 43 } 44 45 TIME_MAPPING = { 46 "YYYY": "%Y", 47 "yyyy": "%Y", 48 "YY": "%y", 49 "yy": "%y", 50 "MMMM": "%B", 51 "mmmm": "%B", 52 "MON": "%b", 53 "mon": "%b", 54 "MM": "%m", 55 "mm": "%m", 56 "DD": "%d", 57 "dd": "%-d", 58 "DY": "%a", 59 "dy": "%w", 60 "HH24": "%H", 61 "hh24": "%H", 62 "HH12": "%I", 63 "hh12": "%I", 64 "MI": "%M", 65 "mi": "%M", 66 "SS": "%S", 67 "ss": "%S", 68 "FF": "%f_nine", # %f_ internal representation with precision specified 69 "ff": "%f_nine", 70 "FF0": "%f_zero", 71 "ff0": "%f_zero", 72 "FF1": "%f_one", 73 "ff1": "%f_one", 74 "FF2": "%f_two", 75 "ff2": "%f_two", 76 "FF3": "%f_three", 77 "ff3": "%f_three", 78 "FF4": "%f_four", 79 "ff4": "%f_four", 80 "FF5": "%f_five", 81 "ff5": "%f_five", 82 "FF6": "%f", 83 "ff6": "%f", 84 "FF7": "%f_seven", 85 "ff7": "%f_seven", 86 "FF8": "%f_eight", 87 "ff8": "%f_eight", 88 "FF9": "%f_nine", 89 "ff9": "%f_nine", 90 "TZHTZM": "%z", 91 "tzhtzm": "%z", 92 "TZH:TZM": "%:z", # internal representation for ±HH:MM 93 "tzh:tzm": "%:z", 94 "TZH": "%-z", # internal representation ±HH 95 "tzh": "%-z", 96 '"T"': "T", # remove the optional double quotes around the separator between the date and time 97 # Seems like Snowflake treats AM/PM in the format string as equivalent, 98 # only the time (stamp) value's AM/PM affects the output 99 "AM": "%p", 100 "am": "%p", 101 "PM": "%p", 102 "pm": "%p", 103 } 104 105 DATE_PART_MAPPING = { 106 **Dialect.DATE_PART_MAPPING, 107 "ISOWEEK": "WEEKISO", 108 # The base Dialect maps EPOCH_SECOND -> EPOCH, but we need to preserve 109 # EPOCH_SECOND as a distinct value for two reasons: 110 # 1. Type annotation: EPOCH_SECOND returns BIGINT, while EPOCH returns DOUBLE 111 # 2. Transpilation: DuckDB's EPOCH() returns float, so we cast EPOCH_SECOND 112 # to BIGINT to match Snowflake's integer behavior 113 # Without this override, EXTRACT(EPOCH_SECOND FROM ts) would be normalized 114 # to EXTRACT(EPOCH FROM ts) and lose the integer semantics. 115 "EPOCH_SECOND": "EPOCH_SECOND", 116 "EPOCH_SECONDS": "EPOCH_SECOND", 117 } 118 119 PSEUDOCOLUMNS = {"LEVEL"} 120 121 def can_quote(self, identifier: exp.Identifier, identify: str | bool = "safe") -> bool: 122 # This disables quoting DUAL in SELECT ... FROM DUAL, because Snowflake treats an 123 # unquoted DUAL keyword in a special way and does not map it to a user-defined table 124 return super().can_quote(identifier, identify) and not ( 125 isinstance(identifier.parent, exp.Table) 126 and not identifier.quoted 127 and identifier.name.lower() == "dual" 128 ) 129 130 class JSONPathTokenizer(jsonpath.JSONPathTokenizer): 131 SINGLE_TOKENS = jsonpath.JSONPathTokenizer.SINGLE_TOKENS.copy() 132 SINGLE_TOKENS.pop("$") 133 134 Parser = SnowflakeParser 135 136 class Tokenizer(tokens.Tokenizer): 137 STRING_ESCAPES = ["\\", "'"] 138 HEX_STRINGS = [("x'", "'"), ("X'", "'")] 139 RAW_STRINGS = ["$$"] 140 COMMENTS = ["--", "//", ("/*", "*/")] 141 NESTED_COMMENTS = False 142 143 KEYWORDS = { 144 **tokens.Tokenizer.KEYWORDS, 145 "BYTEINT": TokenType.INT, 146 "FILE://": TokenType.URI_START, 147 "FILE FORMAT": TokenType.FILE_FORMAT, 148 "GET": TokenType.GET, 149 "INTEGRATION": TokenType.INTEGRATION, 150 "MATCH_CONDITION": TokenType.MATCH_CONDITION, 151 "MATCH_RECOGNIZE": TokenType.MATCH_RECOGNIZE, 152 "MINUS": TokenType.EXCEPT, 153 "NCHAR VARYING": TokenType.VARCHAR, 154 "PACKAGE": TokenType.PACKAGE, 155 "POLICY": TokenType.POLICY, 156 "POOL": TokenType.POOL, 157 "PUT": TokenType.PUT, 158 "UNDROP": TokenType.UNDROP, 159 "REMOVE": TokenType.COMMAND, 160 "RM": TokenType.COMMAND, 161 "ROLE": TokenType.ROLE, 162 "RULE": TokenType.RULE, 163 "SAMPLE": TokenType.TABLE_SAMPLE, 164 "SEMANTIC VIEW": TokenType.SEMANTIC_VIEW, 165 "SQL_DOUBLE": TokenType.DOUBLE, 166 "SQL_VARCHAR": TokenType.VARCHAR, 167 "STAGE": TokenType.STAGE, 168 "STORAGE INTEGRATION": TokenType.STORAGE_INTEGRATION, 169 "STREAMLIT": TokenType.STREAMLIT, 170 "TAG": TokenType.TAG, 171 "TIMESTAMP_TZ": TokenType.TIMESTAMPTZ, 172 "TOP": TokenType.TOP, 173 "VOLUME": TokenType.VOLUME, 174 "WAREHOUSE": TokenType.WAREHOUSE, 175 # https://docs.snowflake.com/en/sql-reference/data-types-numeric#float 176 # FLOAT is a synonym for DOUBLE in Snowflake 177 "FLOAT": TokenType.DOUBLE, 178 } 179 KEYWORDS.pop("/*+") 180 181 SINGLE_TOKENS = { 182 **tokens.Tokenizer.SINGLE_TOKENS, 183 "$": TokenType.PARAMETER, 184 "!": TokenType.EXCLAMATION, 185 } 186 187 VAR_SINGLE_TOKENS = {"$"} 188 189 COMMANDS = tokens.Tokenizer.COMMANDS - {TokenType.SHOW} 190 191 Generator = SnowflakeGenerator
Specifies the strategy according to which identifiers should be normalized.
Mapping of an escaped sequence (\n) to its unescaped version (
).
Default NULL ordering method to use if not explicitly set.
Possible values: "nulls_are_small", "nulls_are_large", "nulls_are_last"
Some dialects, such as Snowflake, allow you to reference a CTE column alias in the HAVING clause of the CTE. This flag will cause the CTE alias columns to override any projection aliases in the subquery.
For example, WITH y(c) AS ( SELECT SUM(a) FROM (SELECT 1 a) AS x HAVING c > 0 ) SELECT c FROM y;
will be rewritten as
WITH y(c) AS (
SELECT SUM(a) AS c FROM (SELECT 1 AS a) AS x HAVING c > 0
) SELECT c FROM y;
Whether Array update functions return NULL when the input array is NULL.
Whether alias references are allowed in JOIN ... ON clauses.
Most dialects do not support this, but Snowflake allows alias expansion in the JOIN ... ON clause (and almost everywhere else)
For example, in Snowflake: SELECT a.id AS user_id FROM a JOIN b ON user_id = b.id -- VALID
Reference: sqlglot.dialects.snowflake.com/en/sql-reference/sql/select#usage-notes">https://docssqlglot.dialects.snowflake.com/en/sql-reference/sql/select#usage-notes
Whether LEAST/GREATEST functions ignore NULL values, e.g:
- BigQuery, Snowflake, MySQL, Presto/Trino: LEAST(1, NULL, 2) -> NULL
- Spark, Postgres, DuckDB, TSQL: LEAST(1, NULL, 2) -> 1
Associates this dialect's time formats with their equivalent Python strftime formats.
Columns that are auto-generated by the engine corresponding to this dialect.
For example, such columns may be excluded from SELECT * queries.
121 def can_quote(self, identifier: exp.Identifier, identify: str | bool = "safe") -> bool: 122 # This disables quoting DUAL in SELECT ... FROM DUAL, because Snowflake treats an 123 # unquoted DUAL keyword in a special way and does not map it to a user-defined table 124 return super().can_quote(identifier, identify) and not ( 125 isinstance(identifier.parent, exp.Table) 126 and not identifier.quoted 127 and identifier.name.lower() == "dual" 128 )
Checks if an identifier can be quoted
Arguments:
- identifier: The identifier to check.
- identify:
True: Always returnsTrueexcept for certain cases."safe": Only returnsTrueif the identifier is case-insensitive."unsafe": Only returnsTrueif the identifier is case-sensitive.
Returns:
Whether the given text can be identified.
Whether string literals support escape sequences (e.g. \n). Set by the metaclass based on the tokenizer's STRING_ESCAPES.
Whether byte string literals support escape sequences. Set by the metaclass based on the tokenizer's BYTE_STRING_ESCAPES.
130 class JSONPathTokenizer(jsonpath.JSONPathTokenizer): 131 SINGLE_TOKENS = jsonpath.JSONPathTokenizer.SINGLE_TOKENS.copy() 132 SINGLE_TOKENS.pop("$")
Inherited Members
- sqlglot.tokens.Tokenizer
- Tokenizer
- BIT_STRINGS
- BYTE_STRINGS
- HEX_STRINGS
- RAW_STRINGS
- HEREDOC_STRINGS
- UNICODE_STRINGS
- IDENTIFIERS
- QUOTES
- VAR_SINGLE_TOKENS
- ESCAPE_FOLLOW_CHARS
- HEREDOC_TAG_IS_IDENTIFIER
- HEREDOC_STRING_ALTERNATIVE
- STRING_ESCAPES_ALLOWED_IN_RAW_STRINGS
- NESTED_COMMENTS
- HINT_START
- TOKENS_PRECEDING_HINT
- COMMANDS
- COMMAND_PREFIX_TOKENS
- NUMERIC_LITERALS
- COMMENTS
- dialect
- tokenize
- sql
- size
- tokens
136 class Tokenizer(tokens.Tokenizer): 137 STRING_ESCAPES = ["\\", "'"] 138 HEX_STRINGS = [("x'", "'"), ("X'", "'")] 139 RAW_STRINGS = ["$$"] 140 COMMENTS = ["--", "//", ("/*", "*/")] 141 NESTED_COMMENTS = False 142 143 KEYWORDS = { 144 **tokens.Tokenizer.KEYWORDS, 145 "BYTEINT": TokenType.INT, 146 "FILE://": TokenType.URI_START, 147 "FILE FORMAT": TokenType.FILE_FORMAT, 148 "GET": TokenType.GET, 149 "INTEGRATION": TokenType.INTEGRATION, 150 "MATCH_CONDITION": TokenType.MATCH_CONDITION, 151 "MATCH_RECOGNIZE": TokenType.MATCH_RECOGNIZE, 152 "MINUS": TokenType.EXCEPT, 153 "NCHAR VARYING": TokenType.VARCHAR, 154 "PACKAGE": TokenType.PACKAGE, 155 "POLICY": TokenType.POLICY, 156 "POOL": TokenType.POOL, 157 "PUT": TokenType.PUT, 158 "UNDROP": TokenType.UNDROP, 159 "REMOVE": TokenType.COMMAND, 160 "RM": TokenType.COMMAND, 161 "ROLE": TokenType.ROLE, 162 "RULE": TokenType.RULE, 163 "SAMPLE": TokenType.TABLE_SAMPLE, 164 "SEMANTIC VIEW": TokenType.SEMANTIC_VIEW, 165 "SQL_DOUBLE": TokenType.DOUBLE, 166 "SQL_VARCHAR": TokenType.VARCHAR, 167 "STAGE": TokenType.STAGE, 168 "STORAGE INTEGRATION": TokenType.STORAGE_INTEGRATION, 169 "STREAMLIT": TokenType.STREAMLIT, 170 "TAG": TokenType.TAG, 171 "TIMESTAMP_TZ": TokenType.TIMESTAMPTZ, 172 "TOP": TokenType.TOP, 173 "VOLUME": TokenType.VOLUME, 174 "WAREHOUSE": TokenType.WAREHOUSE, 175 # https://docs.snowflake.com/en/sql-reference/data-types-numeric#float 176 # FLOAT is a synonym for DOUBLE in Snowflake 177 "FLOAT": TokenType.DOUBLE, 178 } 179 KEYWORDS.pop("/*+") 180 181 SINGLE_TOKENS = { 182 **tokens.Tokenizer.SINGLE_TOKENS, 183 "$": TokenType.PARAMETER, 184 "!": TokenType.EXCLAMATION, 185 } 186 187 VAR_SINGLE_TOKENS = {"$"} 188 189 COMMANDS = tokens.Tokenizer.COMMANDS - {TokenType.SHOW}
Inherited Members
- sqlglot.tokens.Tokenizer
- Tokenizer
- BIT_STRINGS
- BYTE_STRINGS
- HEREDOC_STRINGS
- UNICODE_STRINGS
- IDENTIFIERS
- QUOTES
- ESCAPE_FOLLOW_CHARS
- IDENTIFIER_ESCAPES
- HEREDOC_TAG_IS_IDENTIFIER
- HEREDOC_STRING_ALTERNATIVE
- STRING_ESCAPES_ALLOWED_IN_RAW_STRINGS
- HINT_START
- TOKENS_PRECEDING_HINT
- COMMAND_PREFIX_TOKENS
- NUMERIC_LITERALS
- NUMBERS_CAN_HAVE_DECIMALS
- dialect
- tokenize
- sql
- size
- tokens