From b128031907bd4f1434c10fd8627d168de5bc42c2 Mon Sep 17 00:00:00 2001
From: Seoyoung Lee <lsyhime@snu.ac.kr>
Date: Fri, 21 Oct 2022 12:37:52 +0900
Subject: [PATCH 1/3] parse alter table drop primary key

---
 src/ast/ddl.rs            |  5 +++++
 src/parser.rs             |  3 +++
 tests/sqlparser_common.rs | 12 ++++++++++++
 3 files changed, 20 insertions(+)

diff --git a/src/ast/ddl.rs b/src/ast/ddl.rs
index cae0f597b..c758b4f55 100644
--- a/src/ast/ddl.rs
+++ b/src/ast/ddl.rs
@@ -44,6 +44,10 @@ pub enum AlterTableOperation {
         if_exists: bool,
         cascade: bool,
     },
+    /// `DROP PRIMARY KEY`
+    ///
+    /// Note: this is a MySQL-specific operation.
+    DropPrimaryKey,
     /// `RENAME TO PARTITION (partition=val)`
     RenamePartitions {
         old_partitions: Vec<Expr>,
@@ -124,6 +128,7 @@ impl fmt::Display for AlterTableOperation {
                     if *cascade { " CASCADE" } else { "" },
                 )
             }
+            AlterTableOperation::DropPrimaryKey => write!(f, "DROP PRIMARY KEY"),
             AlterTableOperation::DropColumn {
                 column_name,
                 if_exists,
diff --git a/src/parser.rs b/src/parser.rs
index 108427889..d69dc3552 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -3136,6 +3136,9 @@ impl<'a> Parser<'a> {
                     name,
                     cascade,
                 }
+            } else if self.parse_keyword(Keyword::PRIMARY) {
+                let _ = self.parse_keyword(Keyword::KEY);
+                AlterTableOperation::DropPrimaryKey
             } else {
                 let _ = self.parse_keyword(Keyword::COLUMN);
                 let if_exists = self.parse_keywords(&[Keyword::IF, Keyword::EXISTS]);
diff --git a/tests/sqlparser_common.rs b/tests/sqlparser_common.rs
index bae310ef0..3ee4539ed 100644
--- a/tests/sqlparser_common.rs
+++ b/tests/sqlparser_common.rs
@@ -2778,6 +2778,18 @@ fn parse_alter_table_drop_constraint() {
     );
 }
 
+#[test]
+fn parse_alter_table_drop_primary_key() {
+    match verified_stmt("ALTER TABLE tab DROP PRIMARY KEY") {
+        Statement::AlterTable {
+            name,
+            operation:
+            AlterTableOperation::DropPrimaryKey,
+        } => { assert_eq!("tab", name.to_string()); }
+        _ => unreachable!(),
+    }
+}
+
 #[test]
 fn parse_bad_constraint() {
     let res = parse_sql_statements("ALTER TABLE tab ADD");

From 6e0616ad82ac693dc8de3de7d2311f3b57143c68 Mon Sep 17 00:00:00 2001
From: Seoyoung Lee <lsyhime@snu.ac.kr>
Date: Fri, 21 Oct 2022 12:46:01 +0900
Subject: [PATCH 2/3] cargo nightly fmt

---
 tests/sqlparser_common.rs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/tests/sqlparser_common.rs b/tests/sqlparser_common.rs
index 3ee4539ed..07acc0ef2 100644
--- a/tests/sqlparser_common.rs
+++ b/tests/sqlparser_common.rs
@@ -2783,9 +2783,10 @@ fn parse_alter_table_drop_primary_key() {
     match verified_stmt("ALTER TABLE tab DROP PRIMARY KEY") {
         Statement::AlterTable {
             name,
-            operation:
-            AlterTableOperation::DropPrimaryKey,
-        } => { assert_eq!("tab", name.to_string()); }
+            operation: AlterTableOperation::DropPrimaryKey,
+        } => {
+            assert_eq!("tab", name.to_string());
+        }
         _ => unreachable!(),
     }
 }

From 11cab1f194bf4bb0f32efd0e7ee6bafd2bd9bea3 Mon Sep 17 00:00:00 2001
From: Seoyoung Lee <lsyhime@snu.ac.kr>
Date: Tue, 1 Nov 2022 05:14:51 +0900
Subject: [PATCH 3/3] add Dialect validation

---
 src/parser.rs             |  5 +++--
 tests/sqlparser_common.rs | 13 -------------
 tests/sqlparser_mysql.rs  | 13 +++++++++++++
 3 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/src/parser.rs b/src/parser.rs
index d69dc3552..d1c2911fc 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -3136,8 +3136,9 @@ impl<'a> Parser<'a> {
                     name,
                     cascade,
                 }
-            } else if self.parse_keyword(Keyword::PRIMARY) {
-                let _ = self.parse_keyword(Keyword::KEY);
+            } else if self.parse_keywords(&[Keyword::PRIMARY, Keyword::KEY])
+                && dialect_of!(self is MySqlDialect | GenericDialect)
+            {
                 AlterTableOperation::DropPrimaryKey
             } else {
                 let _ = self.parse_keyword(Keyword::COLUMN);
diff --git a/tests/sqlparser_common.rs b/tests/sqlparser_common.rs
index 07acc0ef2..bae310ef0 100644
--- a/tests/sqlparser_common.rs
+++ b/tests/sqlparser_common.rs
@@ -2778,19 +2778,6 @@ fn parse_alter_table_drop_constraint() {
     );
 }
 
-#[test]
-fn parse_alter_table_drop_primary_key() {
-    match verified_stmt("ALTER TABLE tab DROP PRIMARY KEY") {
-        Statement::AlterTable {
-            name,
-            operation: AlterTableOperation::DropPrimaryKey,
-        } => {
-            assert_eq!("tab", name.to_string());
-        }
-        _ => unreachable!(),
-    }
-}
-
 #[test]
 fn parse_bad_constraint() {
     let res = parse_sql_statements("ALTER TABLE tab ADD");
diff --git a/tests/sqlparser_mysql.rs b/tests/sqlparser_mysql.rs
index 8c42c715b..52c0205d6 100644
--- a/tests/sqlparser_mysql.rs
+++ b/tests/sqlparser_mysql.rs
@@ -875,6 +875,19 @@ fn parse_update_with_joins() {
     }
 }
 
+#[test]
+fn parse_alter_table_drop_primary_key() {
+    match mysql_and_generic().verified_stmt("ALTER TABLE tab DROP PRIMARY KEY") {
+        Statement::AlterTable {
+            name,
+            operation: AlterTableOperation::DropPrimaryKey,
+        } => {
+            assert_eq!("tab", name.to_string());
+        }
+        _ => unreachable!(),
+    }
+}
+
 #[test]
 fn parse_alter_table_change_column() {
     let expected_name = ObjectName(vec![Ident::new("orders")]);