Feat(databricks): shallow clone

tobymao · Aug 30, 2023 · c3d013b · c3d013b
1 parent 6a0110a
commit c3d013b
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Showing 4 changed files with 14 additions and 3 deletions.
diff --git a/sqlglot/expressions.py b/sqlglot/expressions.py
@@ -1035,6 +1035,7 @@ class Clone(Expression):
         "this": True,
         "when": False,
         "kind": False,
+        "shallow": False,
         "expression": False,
     }
 

diff --git a/sqlglot/generator.py b/sqlglot/generator.py
@@ -793,14 +793,16 @@ def create_sql(self, expression: exp.Create) -> str:
 
     def clone_sql(self, expression: exp.Clone) -> str:
         this = self.sql(expression, "this")
+        shallow = "SHALLOW " if expression.args.get("shallow") else ""
+        this = f"{shallow}CLONE {this}"
         when = self.sql(expression, "when")
 
         if when:
             kind = self.sql(expression, "kind")
             expr = self.sql(expression, "expression")
-            return f"CLONE {this} {when} ({kind} => {expr})"
+            return f"{this} {when} ({kind} => {expr})"
 
-        return f"CLONE {this}"
+        return this
 
     def describe_sql(self, expression: exp.Describe) -> str:
         return f"DESCRIBE {self.sql(expression, 'this')}"

diff --git a/sqlglot/parser.py b/sqlglot/parser.py
@@ -1303,6 +1303,8 @@ def extend_props(temp_props: t.Optional[exp.Properties]) -> None:
                 if self._match_text_seq("WITH", "NO", "SCHEMA", "BINDING"):
                     no_schema_binding = True
 
+            shallow = self._match_text_seq("SHALLOW")
+
             if self._match_text_seq("CLONE"):
                 clone = self._parse_table(schema=True)
                 when = self._match_texts({"AT", "BEFORE"}) and self._prev.text.upper()
@@ -1314,7 +1316,12 @@ def extend_props(temp_props: t.Optional[exp.Properties]) -> None:
                 clone_expression = self._match(TokenType.FARROW) and self._parse_bitwise()
                 self._match(TokenType.R_PAREN)
                 clone = self.expression(
-                    exp.Clone, this=clone, when=when, kind=clone_kind, expression=clone_expression
+                    exp.Clone,
+                    this=clone,
+                    when=when,
+                    kind=clone_kind,
+                    shallow=shallow,
+                    expression=clone_expression,
                 )
 
         return self.expression(

diff --git a/tests/dialects/test_databricks.py b/tests/dialects/test_databricks.py
@@ -5,6 +5,7 @@ class TestDatabricks(Validator):
     dialect = "databricks"
 
     def test_databricks(self):
+        self.validate_identity("CREATE TABLE target SHALLOW CLONE source")
         self.validate_identity("INSERT INTO a REPLACE WHERE cond VALUES (1), (2)")
         self.validate_identity("SELECT c1 : price")
         self.validate_identity("CREATE FUNCTION a.b(x INT) RETURNS INT RETURN x + 1")