feat: Add support for UUID function

Author: VaggelisD

sqlglot/dialects/bigquery.py

@@ -724,6 +724,7 @@ class Generator(generator.Generator):
             exp.Unhex: rename_func("FROM_HEX"),
             exp.UnixDate: rename_func("UNIX_DATE"),
             exp.UnixToTime: _unix_to_time_sql,
+            exp.Uuid: lambda *_: "GENERATE_UUID()",
             exp.Values: _derived_table_values_to_unnest,
             exp.VariancePop: rename_func("VAR_POP"),
         }

sqlglot/dialects/postgres.py

@@ -557,6 +557,7 @@ class Generator(generator.Generator):
             exp.TsOrDsAdd: _date_add_sql("+"),
             exp.TsOrDsDiff: _date_diff_sql,
             exp.UnixToTime: lambda self, e: self.func("TO_TIMESTAMP", e.this),
+            exp.Uuid: lambda *_: "GEN_RANDOM_UUID()",
             exp.TimeToUnix: lambda self, e: self.func(
                 "DATE_PART", exp.Literal.string("epoch"), e.this
             ),

sqlglot/dialects/snowflake.py

@@ -848,6 +848,7 @@ class Generator(generator.Generator):
                 "TRY_TO_DATE" if e.args.get("safe") else "TO_DATE", e.this, self.format_time(e)
             ),
             exp.UnixToTime: rename_func("TO_TIMESTAMP"),
+            exp.Uuid: rename_func("UUID_STRING"),
             exp.VarMap: lambda self, e: var_map_sql(self, e, "OBJECT_CONSTRUCT"),
             exp.WeekOfYear: rename_func("WEEKOFYEAR"),
             exp.Xor: rename_func("BOOLXOR"),

sqlglot/expressions.py

@@ -6217,6 +6217,12 @@ class UnixToTimeStr(Func):
     pass
 
 
+class Uuid(Func):
+    _sql_names = ["UUID", "GEN_RANDOM_UUID", "GENERATE_UUID", "UUID_STRING"]
+
+    arg_types = {"this": False, "name": False}
+
+
 class TimestampFromParts(Func):
     _sql_names = ["TIMESTAMP_FROM_PARTS", "TIMESTAMPFROMPARTS"]
     arg_types = {

sqlglot/generator.py

@@ -154,6 +154,7 @@ class Generator(metaclass=_Generator):
         exp.TransientProperty: lambda *_: "TRANSIENT",
         exp.Union: lambda self, e: self.set_operations(e),
         exp.UnloggedProperty: lambda *_: "UNLOGGED",
+        exp.Uuid: lambda *_: "UUID()",
         exp.UppercaseColumnConstraint: lambda *_: "UPPERCASE",
         exp.VarMap: lambda self, e: self.func("MAP", e.args["keys"], e.args["values"]),
         exp.ViewAttributeProperty: lambda self, e: f"WITH {self.sql(e, 'this')}",

tests/dialects/test_dialect.py

@@ -2853,3 +2853,32 @@ def test_trim(self):
                 "bigquery": "RTRIM('Hello World', 'd')",
             },
         )
+
+    def test_uuid(self):
+        self.validate_all(
+            "UUID()",
+            read={
+                "hive": "UUID()",
+                "spark2": "UUID()",
+                "spark": "UUID()",
+                "databricks": "UUID()",
+                "duckdb": "UUID()",
+                "presto": "UUID()",
+                "trino": "UUID()",
+                "postgres": "GEN_RANDOM_UUID()",
+                "bigquery": "GENERATE_UUID()",
+                "snowflake": "UUID_STRING()",
+            },
+            write={
+                "hive": "UUID()",
+                "spark2": "UUID()",
+                "spark": "UUID()",
+                "databricks": "UUID()",
+                "duckdb": "UUID()",
+                "presto": "UUID()",
+                "trino": "UUID()",
+                "postgres": "GEN_RANDOM_UUID()",
+                "bigquery": "GENERATE_UUID()",
+                "snowflake": "UUID_STRING()",
+            },
+        )

tests/dialects/test_snowflake.py

@@ -904,6 +904,28 @@ def test_snowflake(self):
             },
         )
 
+        self.validate_identity(
+            "SELECT UUID_STRING(), UUID_STRING('fe971b24-9572-4005-b22f-351e9c09274d', 'foo')"
+        )
+
+        self.validate_all(
+            "UUID_STRING('fe971b24-9572-4005-b22f-351e9c09274d', 'foo')",
+            read={
+                "snowflake": "UUID_STRING('fe971b24-9572-4005-b22f-351e9c09274d', 'foo')",
+            },
+            write={
+                "hive": "UUID()",
+                "spark2": "UUID()",
+                "spark": "UUID()",
+                "databricks": "UUID()",
+                "duckdb": "UUID()",
+                "presto": "UUID()",
+                "trino": "UUID()",
+                "postgres": "GEN_RANDOM_UUID()",
+                "bigquery": "GENERATE_UUID()",
+            },
+        )
+
     def test_null_treatment(self):
         self.validate_all(
             r"SELECT FIRST_VALUE(TABLE1.COLUMN1) OVER (PARTITION BY RANDOM_COLUMN1, RANDOM_COLUMN2 ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS MY_ALIAS FROM TABLE1",