Postgres: Support parenthesized SET options for ALTER TABLE (#1947)

Co-authored-by: Ifeanyi Ubah <ify1992@yahoo.com>

src/ast/ddl.rs

@@ -351,6 +351,16 @@ pub enum AlterTableOperation {
     ValidateConstraint {
         name: Ident,
     },
+    /// Arbitrary parenthesized `SET` options.
+    ///
+    /// Example:
+    /// ```sql
+    /// SET (scale_factor = 0.01, threshold = 500)`
+    /// ```
+    /// [PostgreSQL](https://www.postgresql.org/docs/current/sql-altertable.html)
+    SetOptionsParens {
+        options: Vec<SqlOption>,
+    },
 }
 
 /// An `ALTER Policy` (`Statement::AlterPolicy`) operation
@@ -791,6 +801,9 @@ impl fmt::Display for AlterTableOperation {
             AlterTableOperation::ValidateConstraint { name } => {
                 write!(f, "VALIDATE CONSTRAINT {name}")
             }
+            AlterTableOperation::SetOptionsParens { options } => {
+                write!(f, "SET ({})", display_comma_separated(options))
+            }
         }
     }
 }

src/ast/spans.rs

@@ -1202,6 +1202,9 @@ impl Spanned for AlterTableOperation {
             AlterTableOperation::Lock { .. } => Span::empty(),
             AlterTableOperation::ReplicaIdentity { .. } => Span::empty(),
             AlterTableOperation::ValidateConstraint { name } => name.span,
+            AlterTableOperation::SetOptionsParens { options } => {
+                union_spans(options.iter().map(|i| i.span()))
+            }
         }
     }
 }

src/parser/mod.rs

@@ -9045,18 +9045,23 @@ impl<'a> Parser<'a> {
             let name = self.parse_identifier()?;
             AlterTableOperation::ValidateConstraint { name }
         } else {
-            let options: Vec<SqlOption> =
+            let mut options =
                 self.parse_options_with_keywords(&[Keyword::SET, Keyword::TBLPROPERTIES])?;
             if !options.is_empty() {
                 AlterTableOperation::SetTblProperties {
                     table_properties: options,
                 }
+            } else {
+                options = self.parse_options(Keyword::SET)?;
+                if !options.is_empty() {
+                    AlterTableOperation::SetOptionsParens { options }
                 } else {
                     return self.expected(
-                    "ADD, RENAME, PARTITION, SWAP, DROP, REPLICA IDENTITY, or SET TBLPROPERTIES after ALTER TABLE",
+                    "ADD, RENAME, PARTITION, SWAP, DROP, REPLICA IDENTITY, SET, or SET TBLPROPERTIES after ALTER TABLE",
                     self.peek_token(),
                   );
                 }
+            }
         };
         Ok(operation)
     }

tests/sqlparser_common.rs

@@ -4728,6 +4728,34 @@ fn parse_alter_table() {
         }
         _ => unreachable!(),
     }
+
+    let set_storage_parameters = "ALTER TABLE tab SET (autovacuum_vacuum_scale_factor = 0.01, autovacuum_vacuum_threshold = 500)";
+    match alter_table_op(verified_stmt(set_storage_parameters)) {
+        AlterTableOperation::SetOptionsParens { options } => {
+            assert_eq!(
+                options,
+                [
+                    SqlOption::KeyValue {
+                        key: Ident {
+                            value: "autovacuum_vacuum_scale_factor".to_string(),
+                            quote_style: None,
+                            span: Span::empty(),
+                        },
+                        value: Expr::Value(test_utils::number("0.01").with_empty_span()),
+                    },
+                    SqlOption::KeyValue {
+                        key: Ident {
+                            value: "autovacuum_vacuum_threshold".to_string(),
+                            quote_style: None,
+                            span: Span::empty(),
+                        },
+                        value: Expr::Value(test_utils::number("500").with_empty_span()),
+                    }
+                ],
+            );
+        }
+        _ => unreachable!(),
+    }
 }
 
 #[test]