feat(snowflake): add UUID_IS_STRING_TYPE flag and UUID_STRING parser

- Set UUID_IS_STRING_TYPE = True in Snowflake dialect
- Add UUID_STRING parser that sets is_string=True flag
- Explicitly set UUID_IS_STRING_TYPE = False in Hive, Presto, and DuckDB dialects

Author: fivetran-ashashankar

sqlglot/dialects/duckdb.py

@@ -24,6 +24,7 @@ class DuckDB(Dialect):
     SUPPORTS_FIXED_SIZE_ARRAYS = True
     STRICT_JSON_PATH_SYNTAX = False
     NUMBERS_CAN_BE_UNDERSCORE_SEPARATED = True
+    UUID_IS_STRING_TYPE = False
 
     # https://duckdb.org/docs/sql/introduction.html#creating-a-new-table
     NORMALIZATION_STRATEGY = NormalizationStrategy.CASE_INSENSITIVE

sqlglot/dialects/hive.py

@@ -24,6 +24,7 @@ class Hive(Dialect):
     ARRAY_AGG_INCLUDES_NULLS = None
     REGEXP_EXTRACT_DEFAULT_GROUP = 1
     ALTER_TABLE_SUPPORTS_CASCADE = True
+    UUID_IS_STRING_TYPE = False
 
     # https://spark.apache.org/docs/latest/sql-ref-identifier.html#description
     NORMALIZATION_STRATEGY = NormalizationStrategy.CASE_INSENSITIVE

sqlglot/dialects/presto.py

@@ -24,6 +24,7 @@ class Presto(Dialect):
     LOG_BASE_FIRST: bool | None = None
     SUPPORTS_VALUES_DEFAULT = False
     LEAST_GREATEST_IGNORES_NULLS = False
+    UUID_IS_STRING_TYPE = False
 
     TIME_MAPPING = MySQL.TIME_MAPPING
 

sqlglot/dialects/snowflake.py

@@ -28,6 +28,7 @@ class Snowflake(Dialect):
     TRY_CAST_REQUIRES_STRING = True
     SUPPORTS_ALIAS_REFS_IN_JOIN_CONDITIONS = True
     LEAST_GREATEST_IGNORES_NULLS = False
+    UUID_IS_STRING_TYPE = True
 
     EXPRESSION_METADATA = EXPRESSION_METADATA.copy()
 

sqlglot/parsers/snowflake.py

@@ -715,6 +715,7 @@ class SnowflakeParser(parser.Parser):
         ),
         "SYSTIMESTAMP": exp.CurrentTimestamp.from_arg_list,
         "UNICODE": lambda args: exp.Unicode(this=seq_get(args, 0), empty_is_zero=True),
+        "UUID_STRING": lambda args: exp.Uuid(this=seq_get(args, 0), name=seq_get(args, 1)),
         "WEEKISO": exp.WeekOfYear.from_arg_list,
         "WEEKOFYEAR": exp.Week.from_arg_list,
     }