PostgreSQL: Support ALTER INDEX ATTACH PARTITION

fuzz/fuzz_seeds/postgres_alter_index_attach_partition.sql

@@ -0,0 +1 @@
+ALTER INDEX d.orders_note_idx ATTACH PARTITION d.p0_note_idx

src/ast/ddl.rs

@@ -803,6 +803,13 @@ pub enum AlterIndexOperation {
         /// The new name for the index.
         index_name: ObjectName,
     },
+    /// Attach the partition index `index_name` to the index.
+    ///
+    /// See <https://www.postgresql.org/docs/current/sql-alterindex.html>
+    AttachPartition {
+        /// The partition index to attach.
+        index_name: ObjectName,
+    },
 }
 
 impl fmt::Display for AlterTableOperation {
@@ -1188,6 +1195,9 @@ impl fmt::Display for AlterIndexOperation {
             AlterIndexOperation::RenameIndex { index_name } => {
                 write!(f, "RENAME TO {index_name}")
             }
+            AlterIndexOperation::AttachPartition { index_name } => {
+                write!(f, "ATTACH PARTITION {index_name}")
+            }
         }
     }
 }

src/ast/spans.rs

@@ -1479,6 +1479,7 @@ impl Spanned for AlterIndexOperation {
     fn span(&self) -> Span {
         match self {
             AlterIndexOperation::RenameIndex { index_name } => index_name.span(),
+            AlterIndexOperation::AttachPartition { index_name } => index_name.span(),
         }
     }
 }

src/parser/mod.rs

@@ -11941,8 +11941,15 @@ impl<'a> Parser<'a> {
                     } else {
                         return self.expected_ref("TO after RENAME", self.peek_token_ref());
                     }
+                } else if self.parse_keyword(Keyword::ATTACH) {
+                    self.expect_keyword_is(Keyword::PARTITION)?;
+                    let index_name = self.parse_object_name(false)?;
+                    AlterIndexOperation::AttachPartition { index_name }
                 } else {
-                    return self.expected_ref("RENAME after ALTER INDEX", self.peek_token_ref());
+                    return self.expected_ref(
+                        "RENAME or ATTACH PARTITION after ALTER INDEX",
+                        self.peek_token_ref(),
+                    );
                 };
 
                 Ok(Statement::AlterIndex {

tests/sqlparser_postgres.rs

@@ -13144,3 +13144,40 @@ fn parse_alter_table_no_inherit() {
         );
     }
 }
+
+#[test]
+fn parse_alter_index_attach_partition() {
+    let sql = "ALTER INDEX d.orders_note_idx ATTACH PARTITION d.p0_note_idx";
+    assert_eq!(
+        Parser::parse_sql(&PostgreSqlDialect {}, sql).unwrap()[0].span(),
+        Span::new(Location::new(1, 13), Location::new(1, 61))
+    );
+    match pg().verified_stmt(sql) {
+        Statement::AlterIndex {
+            name,
+            operation: AlterIndexOperation::AttachPartition { index_name },
+        } => {
+            assert_eq!("d.orders_note_idx", name.to_string());
+            assert_eq!("d.p0_note_idx", index_name.to_string());
+        }
+        _ => unreachable!(),
+    }
+
+    for (sql, expected) in [
+        ("ALTER INDEX i ATTACH p", "Expected: PARTITION, found: p"),
+        (
+            "ALTER INDEX i ATTACH PARTITION",
+            "Expected: identifier, found: EOF",
+        ),
+        (
+            "ALTER INDEX i DETACH PARTITION p",
+            "Expected: RENAME or ATTACH PARTITION after ALTER INDEX, found: DETACH",
+        ),
+    ] {
+        assert_eq!(
+            pg().parse_sql_statements(sql).unwrap_err().to_string(),
+            format!("sql parser error: {expected}"),
+            "{sql}"
+        );
+    }
+}