Merging upstream version 22.2.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 25 insertions, 4 deletions

diff --git a/sqlglot/dialects/presto.py b/sqlglot/dialects/presto.py
index 8429547..3649bd2 100644
--- a/sqlglot/dialects/presto.py
+++ b/sqlglot/dialects/presto.py
@@ -453,11 +453,32 @@ class Presto(Dialect):
             return super().bracket_sql(expression)
 
         def struct_sql(self, expression: exp.Struct) -> str:
-            if any(isinstance(arg, self.KEY_VALUE_DEFINITIONS) for arg in expression.expressions):
-                self.unsupported("Struct with key-value definitions is unsupported.")
-                return self.function_fallback_sql(expression)
+            from sqlglot.optimizer.annotate_types import annotate_types
+
+            expression = annotate_types(expression)
+            values: t.List[str] = []
+            schema: t.List[str] = []
+            unknown_type = False
+
+            for e in expression.expressions:
+                if isinstance(e, exp.PropertyEQ):
+                    if e.type and e.type.is_type(exp.DataType.Type.UNKNOWN):
+                        unknown_type = True
+                    else:
+                        schema.append(f"{self.sql(e, 'this')} {self.sql(e.type)}")
+                    values.append(self.sql(e, "expression"))
+                else:
+                    values.append(self.sql(e))
+
+            size = len(expression.expressions)
 
-            return rename_func("ROW")(self, expression)
+            if not size or len(schema) != size:
+                if unknown_type:
+                    self.unsupported(
+                        "Cannot convert untyped key-value definitions (try annotate_types)."
+                    )
+                return self.func("ROW", *values)
+            return f"CAST(ROW({', '.join(values)}) AS ROW({', '.join(schema)}))"
 
         def interval_sql(self, expression: exp.Interval) -> str:
             unit = self.sql(expression, "unit")