risingwavelabs · mergify · Feb 14, 2023 · Feb 14, 2023 · Feb 14, 2023 · Feb 14, 2023
diff --git a/src/frontend/src/handler/mod.rs b/src/frontend/src/handler/mod.rs
@@ -375,6 +375,7 @@ pub async fn handle(
             name,
             operation: AlterTableOperation::AddColumn { column_def },
         } => alter_table::handle_add_column(handler_args, name, column_def).await,
+        Statement::AlterSystem { param: _, value: _ } => todo!(),
         // Ignore `StartTransaction` and `BEGIN`,`Abort`,`Rollback`,`Commit`temporarily.Its not
         // final implementation.
         // 1. Fully support transaction is too hard and gives few benefits to us.

diff --git a/src/sqlparser/src/ast/mod.rs b/src/sqlparser/src/ast/mod.rs
@@ -1076,6 +1076,11 @@ pub enum Statement {
     CreateUser(CreateUserStatement),
     /// ALTER USER
     AlterUser(AlterUserStatement),
+    /// ALTER SYSTEM SET configuration_parameter { TO | = } { value | 'value' | DEFAULT }
+    AlterSystem {
+        param: Ident,
+        value: SetVariableValue,
+    },
     /// FLUSH the current barrier.
     ///
     /// Note: RisingWave specific statement.
@@ -1512,6 +1517,13 @@ impl fmt::Display for Statement {
             Statement::AlterUser(statement) => {
                 write!(f, "ALTER USER {}", statement)
             }
+            Statement::AlterSystem{param, value} => {
+                f.write_str("ALTER SYSTEM SET ")?;
+                write!(
+                    f,
+                    "{param} = {value}",
+                )
+            }
             Statement::Flush => {
                 write!(f, "FLUSH")
             }
@@ -2184,6 +2196,7 @@ impl fmt::Display for CreateFunctionBody {
 pub enum SetVariableValue {
     Ident(Ident),
     Literal(Value),
+    Default,
 }
 
 impl fmt::Display for SetVariableValue {
@@ -2192,6 +2205,7 @@ impl fmt::Display for SetVariableValue {
         match self {
             Ident(ident) => write!(f, "{}", ident),
             Literal(literal) => write!(f, "{}", literal),
+            Default => write!(f, "DEFAULT"),
         }
     }
 }

diff --git a/src/sqlparser/src/parser.rs b/src/sqlparser/src/parser.rs
@@ -2251,6 +2251,8 @@ impl Parser {
             self.parse_alter_table()
         } else if self.parse_keyword(Keyword::USER) {
             self.parse_alter_user()
+        } else if self.parse_keyword(Keyword::SYSTEM) {
+            self.parse_alter_system()
         } else {
             self.expected("TABLE or USER after ALTER", self.peek_token())
         }
@@ -2347,6 +2349,16 @@ impl Parser {
         })
     }
 
+    pub fn parse_alter_system(&mut self) -> Result<Statement, ParserError> {
+        self.expect_keyword(Keyword::SET)?;
+        let param = self.parse_identifier()?;
+        if self.expect_keyword(Keyword::TO).is_err() && self.expect_token(&Token::Eq).is_err() {
+            return self.expected("TO or = after ALTER SYSTEM SET", self.peek_token());
+        }
+        let value = self.parse_set_variable()?;
+        Ok(Statement::AlterSystem { param, value })
+    }
+
     /// Parse a copy statement
     pub fn parse_copy(&mut self) -> Result<Statement, ParserError> {
         let table_name = self.parse_object_name()?;
@@ -2421,6 +2433,21 @@ impl Parser {
         }
     }
 
+    fn parse_set_variable(&mut self) -> Result<SetVariableValue, ParserError> {
+        let token = self.peek_token();
+        match (self.parse_value(), token) {
+            (Ok(value), _) => Ok(SetVariableValue::Literal(value)),
+            (Err(_), Token::Word(ident)) => {
+                if ident.keyword == Keyword::DEFAULT {
+                    Ok(SetVariableValue::Default)
+                } else {
+                    Ok(SetVariableValue::Ident(ident.to_ident()))
+                }
+            }
+            (Err(_), unexpected) => self.expected("variable value", unexpected),
+        }
+    }
+
     pub fn parse_number_value(&mut self) -> Result<String, ParserError> {
         match self.parse_value()? {
             Value::Number(v) => Ok(v),
@@ -3147,12 +3174,7 @@ impl Parser {
         if self.consume_token(&Token::Eq) || self.parse_keyword(Keyword::TO) {
             let mut values = vec![];
             loop {
-                let token = self.peek_token();
-                let value = match (self.parse_value(), token) {
-                    (Ok(value), _) => SetVariableValue::Literal(value),
-                    (Err(_), Token::Word(ident)) => SetVariableValue::Ident(ident.to_ident()),
-                    (Err(_), unexpected) => self.expected("variable value", unexpected)?,
-                };
+                let value = self.parse_set_variable()?;
                 values.push(value);
                 if self.consume_token(&Token::Comma) {
                     continue;

diff --git a/src/sqlparser/tests/sqlparser_postgres.rs b/src/sqlparser/tests/sqlparser_postgres.rs
@@ -422,7 +422,7 @@ fn parse_set() {
         Statement::SetVariable {
             local: false,
             variable: "a".into(),
-            value: vec![SetVariableValue::Ident("DEFAULT".into())],
+            value: vec![SetVariableValue::Default],
         }
     );
 

diff --git a/src/sqlparser/tests/testdata/alter.yaml b/src/sqlparser/tests/testdata/alter.yaml
@@ -0,0 +1,11 @@
+- input: ALTER USER user WITH SUPERUSER CREATEDB PASSWORD 'password'
+  formatted_sql: ALTER USER user WITH SUPERUSER CREATEDB PASSWORD 'password'
+
+- input: ALTER USER user RENAME TO another
+  formatted_sql: ALTER USER user RENAME TO another
+
+- input: ALTER SYSTEM SET a = 'abc'
+  formatted_sql: ALTER SYSTEM SET a = 'abc'
+
+- input: ALTER SYSTEM SET a = DEFAULT
+  formatted_sql: ALTER SYSTEM SET a = DEFAULT
diff --git a/src/sqlparser/tests/testdata/create.yaml b/src/sqlparser/tests/testdata/create.yaml
@@ -65,12 +65,6 @@
 - input: CREATE USER user WITH SUPERUSER CREATEDB PASSWORD 'password'
   formatted_sql: CREATE USER user WITH SUPERUSER CREATEDB PASSWORD 'password'
 
-- input: ALTER USER user WITH SUPERUSER CREATEDB PASSWORD 'password'
-  formatted_sql: ALTER USER user WITH SUPERUSER CREATEDB PASSWORD 'password'
-
-- input: ALTER USER user RENAME TO another
-  formatted_sql: ALTER USER user RENAME TO another
-
 - input: CREATE SINK snk
   error_msg: |
     sql parser error: Expected FROM or AS after CREATE SINK sink_name, found: EOF