clickhouse: add support for LIMIT BY (#977)

src/ast/query.rs

@@ -35,6 +35,10 @@ pub struct Query {
     pub order_by: Vec<OrderByExpr>,
     /// `LIMIT { <N> | ALL }`
     pub limit: Option<Expr>,
+
+    /// `LIMIT { <N> } BY { <expr>,<expr>,... } }`
+    pub limit_by: Vec<Expr>,
+
     /// `OFFSET <N> [ { ROW | ROWS } ]`
     pub offset: Option<Offset>,
     /// `FETCH { FIRST | NEXT } <N> [ PERCENT ] { ROW | ROWS } | { ONLY | WITH TIES }`
@@ -58,6 +62,9 @@ impl fmt::Display for Query {
         if let Some(ref offset) = self.offset {
             write!(f, " {offset}")?;
         }
+        if !self.limit_by.is_empty() {
+            write!(f, " BY {}", display_separated(&self.limit_by, ", "))?;
+        }
         if let Some(ref fetch) = self.fetch {
             write!(f, " {fetch}")?;
         }

src/parser/mod.rs

@@ -5431,6 +5431,7 @@ impl<'a> Parser<'a> {
                 with,
                 body: Box::new(SetExpr::Insert(insert)),
                 limit: None,
+                limit_by: vec![],
                 order_by: vec![],
                 offset: None,
                 fetch: None,
@@ -5442,6 +5443,7 @@ impl<'a> Parser<'a> {
                 with,
                 body: Box::new(SetExpr::Update(update)),
                 limit: None,
+                limit_by: vec![],
                 order_by: vec![],
                 offset: None,
                 fetch: None,
@@ -5468,7 +5470,7 @@ impl<'a> Parser<'a> {
                     offset = Some(self.parse_offset()?)
                 }
 
-                if dialect_of!(self is GenericDialect | MySqlDialect)
+                if dialect_of!(self is GenericDialect | MySqlDialect | ClickHouseDialect)
                     && limit.is_some()
                     && offset.is_none()
                     && self.consume_token(&Token::Comma)
@@ -5483,6 +5485,14 @@ impl<'a> Parser<'a> {
                 }
             }
 
+            let limit_by = if dialect_of!(self is ClickHouseDialect | GenericDialect)
+                && self.parse_keyword(Keyword::BY)
+            {
+                self.parse_comma_separated(Parser::parse_expr)?
+            } else {
+                vec![]
+            };
+
             let fetch = if self.parse_keyword(Keyword::FETCH) {
                 Some(self.parse_fetch()?)
             } else {
@@ -5499,6 +5509,7 @@ impl<'a> Parser<'a> {
                 body,
                 order_by,
                 limit,
+                limit_by,
                 offset,
                 fetch,
                 locks,

tests/sqlparser_clickhouse.rs

@@ -25,6 +25,7 @@ use sqlparser::ast::TableFactor::Table;
 use sqlparser::ast::*;
 
 use sqlparser::dialect::ClickHouseDialect;
+use sqlparser::dialect::GenericDialect;
 
 #[test]
 fn parse_map_access_expr() {
@@ -344,9 +345,26 @@ fn parse_double_equal() {
     );
 }
 
+#[test]
+fn parse_limit_by() {
+    clickhouse_and_generic().verified_stmt(
+        r#"SELECT * FROM default.last_asset_runs_mv ORDER BY created_at DESC LIMIT 1 BY asset"#,
+    );
+    clickhouse_and_generic().verified_stmt(
+        r#"SELECT * FROM default.last_asset_runs_mv ORDER BY created_at DESC LIMIT 1 BY asset, toStartOfDay(created_at)"#,
+    );
+}
+
 fn clickhouse() -> TestedDialects {
     TestedDialects {
         dialects: vec![Box::new(ClickHouseDialect {})],
         options: None,
     }
 }
+
+fn clickhouse_and_generic() -> TestedDialects {
+    TestedDialects {
+        dialects: vec![Box::new(ClickHouseDialect {}), Box::new(GenericDialect {})],
+        options: None,
+    }
+}

tests/sqlparser_common.rs

@@ -261,6 +261,7 @@ fn parse_update_set_from() {
                         }))),
                         order_by: vec![],
                         limit: None,
+                        limit_by: vec![],
                         offset: None,
                         fetch: None,
                         locks: vec![],
@@ -2662,6 +2663,7 @@ fn parse_create_table_as_table() {
         }))),
         order_by: vec![],
         limit: None,
+        limit_by: vec![],
         offset: None,
         fetch: None,
         locks: vec![],
@@ -2685,6 +2687,7 @@ fn parse_create_table_as_table() {
         }))),
         order_by: vec![],
         limit: None,
+        limit_by: vec![],
         offset: None,
         fetch: None,
         locks: vec![],
@@ -3976,6 +3979,7 @@ fn parse_interval_and_or_xor() {
         }))),
         order_by: vec![],
         limit: None,
+        limit_by: vec![],
         offset: None,
         fetch: None,
         locks: vec![],
@@ -6392,6 +6396,7 @@ fn parse_merge() {
                         }))),
                         order_by: vec![],
                         limit: None,
+                        limit_by: vec![],
                         offset: None,
                         fetch: None,
                         locks: vec![],

tests/sqlparser_mssql.rs

@@ -92,6 +92,7 @@ fn parse_create_procedure() {
             body: vec![Statement::Query(Box::new(Query {
                 with: None,
                 limit: None,
+                limit_by: vec![],
                 offset: None,
                 fetch: None,
                 locks: vec![],
@@ -493,6 +494,7 @@ fn parse_substring_in_select() {
             assert_eq!(
                 Box::new(Query {
                     with: None,
+
                     body: Box::new(SetExpr::Select(Box::new(Select {
                         distinct: Some(Distinct::Distinct),
                         top: None,
@@ -532,6 +534,7 @@ fn parse_substring_in_select() {
                     }))),
                     order_by: vec![],
                     limit: None,
+                    limit_by: vec![],
                     offset: None,
                     fetch: None,
                     locks: vec![],

tests/sqlparser_mysql.rs

@@ -562,6 +562,7 @@ fn parse_escaped_quote_identifiers_with_escape() {
             }))),
             order_by: vec![],
             limit: None,
+            limit_by: vec![],
             offset: None,
             fetch: None,
             locks: vec![],
@@ -604,6 +605,7 @@ fn parse_escaped_quote_identifiers_with_no_escape() {
             }))),
             order_by: vec![],
             limit: None,
+            limit_by: vec![],
             offset: None,
             fetch: None,
             locks: vec![],
@@ -643,6 +645,7 @@ fn parse_escaped_backticks_with_escape() {
             }))),
             order_by: vec![],
             limit: None,
+            limit_by: vec![],
             offset: None,
             fetch: None,
             locks: vec![],
@@ -682,6 +685,7 @@ fn parse_escaped_backticks_with_no_escape() {
             }))),
             order_by: vec![],
             limit: None,
+            limit_by: vec![],
             offset: None,
             fetch: None,
             locks: vec![],
@@ -956,6 +960,7 @@ fn parse_simple_insert() {
                     })),
                     order_by: vec![],
                     limit: None,
+                    limit_by: vec![],
                     offset: None,
                     fetch: None,
                     locks: vec![],
@@ -991,6 +996,7 @@ fn parse_empty_row_insert() {
                     })),
                     order_by: vec![],
                     limit: None,
+                    limit_by: vec![],
                     offset: None,
                     fetch: None,
                     locks: vec![],
@@ -1049,6 +1055,7 @@ fn parse_insert_with_on_duplicate_update() {
                     })),
                     order_by: vec![],
                     limit: None,
+                    limit_by: vec![],
                     offset: None,
                     fetch: None,
                     locks: vec![],
@@ -1428,6 +1435,7 @@ fn parse_substring_in_select() {
                     }))),
                     order_by: vec![],
                     limit: None,
+                    limit_by: vec![],
                     offset: None,
                     fetch: None,
                     locks: vec![],
@@ -1708,6 +1716,7 @@ fn parse_hex_string_introducer() {
             }))),
             order_by: vec![],
             limit: None,
+            limit_by: vec![],
             offset: None,
             fetch: None,
             locks: vec![],

tests/sqlparser_postgres.rs

@@ -1000,6 +1000,7 @@ fn parse_copy_to() {
                 }))),
                 order_by: vec![],
                 limit: None,
+                limit_by: vec![],
                 offset: None,
                 fetch: None,
                 locks: vec![],
@@ -2046,6 +2047,7 @@ fn parse_array_subquery_expr() {
             }),
             order_by: vec![],
             limit: None,
+            limit_by: vec![],
             offset: None,
             fetch: None,
             locks: vec![],