feat: Support expression in SET statement (#574)

Co-authored-by: Alex Vasilev <vaspiring@gmail.com>

src/ast/mod.rs

@@ -545,8 +545,10 @@ impl fmt::Display for Expr {
             Expr::UnaryOp { op, expr } => {
                 if op == &UnaryOperator::PGPostfixFactorial {
                     write!(f, "{}{}", expr, op)
-                } else {
+                } else if op == &UnaryOperator::Not {
                     write!(f, "{} {}", op, expr)
+                } else {
+                    write!(f, "{}{}", op, expr)
                 }
             }
             Expr::Cast { expr, data_type } => write!(f, "CAST({} AS {})", expr, data_type),
@@ -1100,7 +1102,7 @@ pub enum Statement {
         local: bool,
         hivevar: bool,
         variable: ObjectName,
-        value: Vec<SetVariableValue>,
+        value: Vec<Expr>,
     },
     /// SET NAMES 'charset_name' [COLLATE 'collation_name']
     ///
@@ -2745,23 +2747,6 @@ impl fmt::Display for ShowStatementFilter {
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-pub enum SetVariableValue {
-    Ident(Ident),
-    Literal(Value),
-}
-
-impl fmt::Display for SetVariableValue {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        use SetVariableValue::*;
-        match self {
-            Ident(ident) => write!(f, "{}", ident),
-            Literal(literal) => write!(f, "{}", literal),
-        }
-    }
-}
-
 /// Sqlite specific syntax
 ///
 /// https://sqlite.org/lang_conflict.html

src/dialect/mysql.rs

@@ -24,6 +24,7 @@ impl Dialect for MySqlDialect {
             || ('A'..='Z').contains(&ch)
             || ch == '_'
             || ch == '$'
+            || ch == '@'
             || ('\u{0080}'..='\u{ffff}').contains(&ch)
     }
 

src/parser.rs

@@ -3751,22 +3751,12 @@ impl<'a> Parser<'a> {
         } else if self.consume_token(&Token::Eq) || self.parse_keyword(Keyword::TO) {
             let mut values = vec![];
             loop {
-                let token = self.peek_token();
+                let value = if let Ok(expr) = self.parse_expr() {
-                let value = match (self.parse_value(), token) {
+                    expr
-                    (Ok(value), _) => SetVariableValue::Literal(value),
+                } else {
-                    (Err(_), Token::Word(ident)) => SetVariableValue::Ident(ident.to_ident()),
+                    self.expected("variable value", self.peek_token())?
-                    (Err(_), Token::Minus) => {
-                        let next_token = self.next_token();
-                        match next_token {
-                            Token::Word(ident) => SetVariableValue::Ident(Ident {
-                                quote_style: ident.quote_style,
-                                value: format!("-{}", ident.value),
-                            }),
-                            _ => self.expected("word", next_token)?,
-                        }
-                    }
-                    (Err(_), unexpected) => self.expected("variable value", unexpected)?,
                 };
+
                 values.push(value);
                 if self.consume_token(&Token::Comma) {
                     continue;

tests/sqlparser_common.rs

@@ -580,7 +580,7 @@ fn parse_select_count_wildcard() {
 
 #[test]
 fn parse_select_count_distinct() {
-    let sql = "SELECT COUNT(DISTINCT + x) FROM customer";
+    let sql = "SELECT COUNT(DISTINCT +x) FROM customer";
     let select = verified_only_select(sql);
     assert_eq!(
         &Expr::Function(Function {
@@ -597,8 +597,8 @@ fn parse_select_count_distinct() {
     );
 
     one_statement_parses_to(
-        "SELECT COUNT(ALL + x) FROM customer",
+        "SELECT COUNT(ALL +x) FROM customer",
-        "SELECT COUNT(+ x) FROM customer",
+        "SELECT COUNT(+x) FROM customer",
     );
 
     let sql = "SELECT COUNT(ALL DISTINCT + x) FROM customer";
@@ -754,7 +754,7 @@ fn parse_compound_expr_2() {
 #[test]
 fn parse_unary_math() {
     use self::Expr::*;
-    let sql = "- a + - b";
+    let sql = "-a + -b";
     assert_eq!(
         BinaryOp {
             left: Box::new(UnaryOp {

tests/sqlparser_hive.rs

@@ -15,7 +15,7 @@
 //! Test SQL syntax specific to Hive. The parser based on the generic dialect
 //! is also tested (on the inputs it can handle).
 
-use sqlparser::ast::{CreateFunctionUsing, Ident, ObjectName, SetVariableValue, Statement};
+use sqlparser::ast::{CreateFunctionUsing, Expr, Ident, ObjectName, Statement, UnaryOperator};
 use sqlparser::dialect::{GenericDialect, HiveDialect};
 use sqlparser::parser::ParserError;
 use sqlparser::test_utils::*;
@@ -220,14 +220,17 @@ fn set_statement_with_minus() {
                 Ident::new("java"),
                 Ident::new("opts")
             ]),
-            value: vec![SetVariableValue::Ident("-Xmx4g".into())],
+            value: vec![Expr::UnaryOp {
+                op: UnaryOperator::Minus,
+                expr: Box::new(Expr::Identifier(Ident::new("Xmx4g")))
+            }],
         }
     );
 
     assert_eq!(
         hive().parse_sql_statements("SET hive.tez.java.opts = -"),
         Err(ParserError::ParserError(
-            "Expected word, found: EOF".to_string()
+            "Expected variable value, found: EOF".to_string()
         ))
     )
 }

tests/sqlparser_mysql.rs

@@ -251,6 +251,26 @@ fn parse_use() {
     );
 }
 
+#[test]
+fn parse_set_variables() {
+    mysql_and_generic().verified_stmt("SET sql_mode = CONCAT(@@sql_mode, ',STRICT_TRANS_TABLES')");
+    assert_eq!(
+        mysql_and_generic().verified_stmt("SET LOCAL autocommit = 1"),
+        Statement::SetVariable {
+            local: true,
+            hivevar: false,
+            variable: ObjectName(vec!["autocommit".into()]),
+            value: vec![Expr::Value(Value::Number(
+                #[cfg(not(feature = "bigdecimal"))]
+                "1".to_string(),
+                #[cfg(feature = "bigdecimal")]
+                bigdecimal::BigDecimal::from(1),
+                false
+            ))],
+        }
+    );
+}
+
 #[test]
 fn parse_create_table_auto_increment() {
     let sql = "CREATE TABLE foo (bar INT PRIMARY KEY AUTO_INCREMENT)";

tests/sqlparser_postgres.rs

@@ -18,7 +18,6 @@
 mod test_utils;
 use test_utils::*;
 
-use sqlparser::ast::Value::Boolean;
 use sqlparser::ast::*;
 use sqlparser::dialect::{GenericDialect, PostgreSqlDialect};
 use sqlparser::parser::ParserError;
@@ -782,7 +781,10 @@ fn parse_set() {
             local: false,
             hivevar: false,
             variable: ObjectName(vec![Ident::new("a")]),
-            value: vec![SetVariableValue::Ident("b".into())],
+            value: vec![Expr::Identifier(Ident {
+                value: "b".into(),
+                quote_style: None
+            })],
         }
     );
 
@@ -793,9 +795,7 @@ fn parse_set() {
             local: false,
             hivevar: false,
             variable: ObjectName(vec![Ident::new("a")]),
-            value: vec![SetVariableValue::Literal(Value::SingleQuotedString(
+            value: vec![Expr::Value(Value::SingleQuotedString("b".into()))],
-                "b".into()
-            ))],
         }
     );
 
@@ -806,7 +806,13 @@ fn parse_set() {
             local: false,
             hivevar: false,
             variable: ObjectName(vec![Ident::new("a")]),
-            value: vec![SetVariableValue::Literal(number("0"))],
+            value: vec![Expr::Value(Value::Number(
+                #[cfg(not(feature = "bigdecimal"))]
+                "0".to_string(),
+                #[cfg(feature = "bigdecimal")]
+                bigdecimal::BigDecimal::from(0),
+                false,
+            ))],
         }
     );
 
@@ -817,7 +823,10 @@ fn parse_set() {
             local: false,
             hivevar: false,
             variable: ObjectName(vec![Ident::new("a")]),
-            value: vec![SetVariableValue::Ident("DEFAULT".into())],
+            value: vec![Expr::Identifier(Ident {
+                value: "DEFAULT".into(),
+                quote_style: None
+            })],
         }
     );
 
@@ -828,7 +837,7 @@ fn parse_set() {
             local: true,
             hivevar: false,
             variable: ObjectName(vec![Ident::new("a")]),
-            value: vec![SetVariableValue::Ident("b".into())],
+            value: vec![Expr::Identifier("b".into())],
         }
     );
 
@@ -839,7 +848,10 @@ fn parse_set() {
             local: false,
             hivevar: false,
             variable: ObjectName(vec![Ident::new("a"), Ident::new("b"), Ident::new("c")]),
-            value: vec![SetVariableValue::Ident("b".into())],
+            value: vec![Expr::Identifier(Ident {
+                value: "b".into(),
+                quote_style: None
+            })],
         }
     );
 
@@ -859,7 +871,7 @@ fn parse_set() {
                 Ident::new("reducer"),
                 Ident::new("parallelism")
             ]),
-            value: vec![SetVariableValue::Literal(Boolean(false))],
+            value: vec![Expr::Value(Value::Boolean(false))],
         }
     );
 
@@ -1107,7 +1119,7 @@ fn parse_pg_unary_ops() {
     ];
 
     for (str_op, op) in pg_unary_ops {
-        let select = pg().verified_only_select(&format!("SELECT {} a", &str_op));
+        let select = pg().verified_only_select(&format!("SELECT {}a", &str_op));
         assert_eq!(
             SelectItem::UnnamedExpr(Expr::UnaryOp {
                 op: op.clone(),