[ClickHouse] Add support for WITH FILL to OrderByExpr (#1330)

Co-authored-by: Andrew Lamb <andrew@nerdnetworks.org>

src/ast/mod.rs

@@ -43,14 +43,15 @@ pub use self::operator::{BinaryOperator, UnaryOperator};
 pub use self::query::{
     AfterMatchSkip, ConnectBy, Cte, CteAsMaterialized, Distinct, EmptyMatchesMode,
     ExceptSelectItem, ExcludeSelectItem, ExprWithAlias, Fetch, ForClause, ForJson, ForXml,
-    FormatClause, GroupByExpr, GroupByWithModifier, IdentWithAlias, IlikeSelectItem, Join,
-    JoinConstraint, JoinOperator, JsonTableColumn, JsonTableColumnErrorHandling, LateralView,
-    LockClause, LockType, MatchRecognizePattern, MatchRecognizeSymbol, Measure,
-    NamedWindowDefinition, NamedWindowExpr, NonBlock, Offset, OffsetRows, OrderByExpr,
-    PivotValueSource, Query, RenameSelectItem, RepetitionQuantifier, ReplaceSelectElement,
-    ReplaceSelectItem, RowsPerMatch, Select, SelectInto, SelectItem, SetExpr, SetOperator,
-    SetQuantifier, Setting, SymbolDefinition, Table, TableAlias, TableFactor, TableVersion,
-    TableWithJoins, Top, TopQuantity, ValueTableMode, Values, WildcardAdditionalOptions, With,
+    FormatClause, GroupByExpr, GroupByWithModifier, IdentWithAlias, IlikeSelectItem, Interpolate,
+    InterpolateExpr, Join, JoinConstraint, JoinOperator, JsonTableColumn,
+    JsonTableColumnErrorHandling, LateralView, LockClause, LockType, MatchRecognizePattern,
+    MatchRecognizeSymbol, Measure, NamedWindowDefinition, NamedWindowExpr, NonBlock, Offset,
+    OffsetRows, OrderBy, OrderByExpr, PivotValueSource, Query, RenameSelectItem,
+    RepetitionQuantifier, ReplaceSelectElement, ReplaceSelectItem, RowsPerMatch, Select,
+    SelectInto, SelectItem, SetExpr, SetOperator, SetQuantifier, Setting, SymbolDefinition, Table,
+    TableAlias, TableFactor, TableVersion, TableWithJoins, Top, TopQuantity, ValueTableMode,
+    Values, WildcardAdditionalOptions, With, WithFill,
 };
 pub use self::value::{
     escape_double_quote_string, escape_quoted_string, DateTimeField, DollarQuotedString,

src/ast/query.rs

@@ -33,7 +33,7 @@ pub struct Query {
     /// SELECT or UNION / EXCEPT / INTERSECT
     pub body: Box<SetExpr>,
     /// ORDER BY
-    pub order_by: Vec<OrderByExpr>,
+    pub order_by: Option<OrderBy>,
     /// `LIMIT { <N> | ALL }`
     pub limit: Option<Expr>,
 
@@ -67,8 +67,17 @@ impl fmt::Display for Query {
             write!(f, "{with} ")?;
         }
         write!(f, "{}", self.body)?;
-        if !self.order_by.is_empty() {
-            write!(f, " ORDER BY {}", display_comma_separated(&self.order_by))?;
+        if let Some(ref order_by) = self.order_by {
+            write!(f, " ORDER BY")?;
+            if !order_by.exprs.is_empty() {
+                write!(f, " {}", display_comma_separated(&order_by.exprs))?;
+            }
+            if let Some(ref interpolate) = order_by.interpolate {
+                match &interpolate.exprs {
+                    Some(exprs) => write!(f, " INTERPOLATE ({})", display_comma_separated(exprs))?,
+                    None => write!(f, " INTERPOLATE")?,
+                }
+            }
         }
         if let Some(ref limit) = self.limit {
             write!(f, " LIMIT {limit}")?;
@@ -1668,6 +1677,18 @@ pub enum JoinConstraint {
     None,
 }
 
+#[derive(Debug, Clone, PartialEq, PartialOrd, Eq, Ord, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "visitor", derive(Visit, VisitMut))]
+pub struct OrderBy {
+    pub exprs: Vec<OrderByExpr>,
+    /// Optional: `INTERPOLATE`
+    /// Supported by [ClickHouse syntax]
+    ///
+    /// [ClickHouse syntax]: <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by#order-by-expr-with-fill-modifier>
+    pub interpolate: Option<Interpolate>,
+}
+
 /// An `ORDER BY` expression
 #[derive(Debug, Clone, PartialEq, PartialOrd, Eq, Ord, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
@@ -1678,6 +1699,9 @@ pub struct OrderByExpr {
     pub asc: Option<bool>,
     /// Optional `NULLS FIRST` or `NULLS LAST`
     pub nulls_first: Option<bool>,
+    /// Optional: `WITH FILL`
+    /// Supported by [ClickHouse syntax]: <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by#order-by-expr-with-fill-modifier>
+    pub with_fill: Option<WithFill>,
 }
 
 impl fmt::Display for OrderByExpr {
@@ -1693,6 +1717,67 @@ impl fmt::Display for OrderByExpr {
             Some(false) => write!(f, " NULLS LAST")?,
             None => (),
         }
+        if let Some(ref with_fill) = self.with_fill {
+            write!(f, " {}", with_fill)?
+        }
+        Ok(())
+    }
+}
+
+/// ClickHouse `WITH FILL` modifier for `ORDER BY` clause.
+/// Supported by [ClickHouse syntax]
+///
+/// [ClickHouse syntax]: <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by#order-by-expr-with-fill-modifier>
+#[derive(Debug, Clone, PartialEq, PartialOrd, Eq, Ord, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "visitor", derive(Visit, VisitMut))]
+pub struct WithFill {
+    pub from: Option<Expr>,
+    pub to: Option<Expr>,
+    pub step: Option<Expr>,
+}
+
+impl fmt::Display for WithFill {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "WITH FILL")?;
+        if let Some(ref from) = self.from {
+            write!(f, " FROM {}", from)?;
+        }
+        if let Some(ref to) = self.to {
+            write!(f, " TO {}", to)?;
+        }
+        if let Some(ref step) = self.step {
+            write!(f, " STEP {}", step)?;
+        }
+        Ok(())
+    }
+}
+
+/// ClickHouse `INTERPOLATE` clause for use in `ORDER BY` clause when using `WITH FILL` modifier.
+/// Supported by [ClickHouse syntax]
+///
+/// [ClickHouse syntax]: <https://clickhouse.com/docs/en/sql-reference/statements/select/order-by#order-by-expr-with-fill-modifier>
+#[derive(Debug, Clone, PartialEq, PartialOrd, Eq, Ord, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "visitor", derive(Visit, VisitMut))]
+pub struct InterpolateExpr {
+    pub column: Ident,
+    pub expr: Option<Expr>,
+}
+
+#[derive(Debug, Clone, PartialEq, PartialOrd, Eq, Ord, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "visitor", derive(Visit, VisitMut))]
+pub struct Interpolate {
+    pub exprs: Option<Vec<InterpolateExpr>>,
+}
+
+impl fmt::Display for InterpolateExpr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.column)?;
+        if let Some(ref expr) = self.expr {
+            write!(f, " AS {}", expr)?;
+        }
         Ok(())
     }
 }

src/keywords.rs

@@ -297,6 +297,7 @@ define_keywords!(
     FILE,
     FILES,
     FILE_FORMAT,
+    FILL,
     FILTER,
     FIRST,
     FIRST_VALUE,
@@ -382,6 +383,7 @@ define_keywords!(
     INT64,
     INT8,
     INTEGER,
+    INTERPOLATE,
     INTERSECT,
     INTERSECTION,
     INTERVAL,
@@ -682,6 +684,7 @@ define_keywords!(
     STDDEV_SAMP,
     STDIN,
     STDOUT,
+    STEP,
     STORAGE_INTEGRATION,
     STORED,
     STRICT,

src/parser/mod.rs

@@ -7934,7 +7934,7 @@ impl<'a> Parser<'a> {
                 body: self.parse_insert_setexpr_boxed()?,
                 limit: None,
                 limit_by: vec![],
-                order_by: vec![],
+                order_by: None,
                 offset: None,
                 fetch: None,
                 locks: vec![],
@@ -7948,7 +7948,7 @@ impl<'a> Parser<'a> {
                 body: self.parse_update_setexpr_boxed()?,
                 limit: None,
                 limit_by: vec![],
-                order_by: vec![],
+                order_by: None,
                 offset: None,
                 fetch: None,
                 locks: vec![],
@@ -7960,9 +7960,19 @@ impl<'a> Parser<'a> {
             let body = self.parse_boxed_query_body(0)?;
 
             let order_by = if self.parse_keywords(&[Keyword::ORDER, Keyword::BY]) {
-                self.parse_comma_separated(Parser::parse_order_by_expr)?
+                let order_by_exprs = self.parse_comma_separated(Parser::parse_order_by_expr)?;
+                let interpolate = if dialect_of!(self is ClickHouseDialect | GenericDialect) {
+                    self.parse_interpolations()?
+                } else {
+                    None
+                };
+
+                Some(OrderBy {
+                    exprs: order_by_exprs,
+                    interpolate,
+                })
             } else {
-                vec![]
+                None
             };
 
             let mut limit = None;
@@ -9193,7 +9203,7 @@ impl<'a> Parser<'a> {
                 subquery: Box::new(Query {
                     with: None,
                     body: Box::new(values),
-                    order_by: vec![],
+                    order_by: None,
                     limit: None,
                     limit_by: vec![],
                     offset: None,
@@ -10519,13 +10529,77 @@ impl<'a> Parser<'a> {
             None
         };
 
+        let with_fill = if dialect_of!(self is ClickHouseDialect | GenericDialect)
+            && self.parse_keywords(&[Keyword::WITH, Keyword::FILL])
+        {
+            Some(self.parse_with_fill()?)
+        } else {
+            None
+        };
+
         Ok(OrderByExpr {
             expr,
             asc,
             nulls_first,
+            with_fill,
         })
     }
 
+    // Parse a WITH FILL clause (ClickHouse dialect)
+    // that follow the WITH FILL keywords in a ORDER BY clause
+    pub fn parse_with_fill(&mut self) -> Result<WithFill, ParserError> {
+        let from = if self.parse_keyword(Keyword::FROM) {
+            Some(self.parse_expr()?)
+        } else {
+            None
+        };
+
+        let to = if self.parse_keyword(Keyword::TO) {
+            Some(self.parse_expr()?)
+        } else {
+            None
+        };
+
+        let step = if self.parse_keyword(Keyword::STEP) {
+            Some(self.parse_expr()?)
+        } else {
+            None
+        };
+
+        Ok(WithFill { from, to, step })
+    }
+
+    // Parse a set of comma seperated INTERPOLATE expressions (ClickHouse dialect)
+    // that follow the INTERPOLATE keyword in an ORDER BY clause with the WITH FILL modifier
+    pub fn parse_interpolations(&mut self) -> Result<Option<Interpolate>, ParserError> {
+        if !self.parse_keyword(Keyword::INTERPOLATE) {
+            return Ok(None);
+        }
+
+        if self.consume_token(&Token::LParen) {
+            let interpolations = self.parse_comma_separated0(|p| p.parse_interpolation())?;
+            self.expect_token(&Token::RParen)?;
+            // INTERPOLATE () and INTERPOLATE ( ... ) variants
+            return Ok(Some(Interpolate {
+                exprs: Some(interpolations),
+            }));
+        }
+
+        // INTERPOLATE
+        Ok(Some(Interpolate { exprs: None }))
+    }
+
+    // Parse a INTERPOLATE expression (ClickHouse dialect)
+    pub fn parse_interpolation(&mut self) -> Result<InterpolateExpr, ParserError> {
+        let column = self.parse_identifier(false)?;
+        let expr = if self.parse_keyword(Keyword::AS) {
+            Some(self.parse_expr()?)
+        } else {
+            None
+        };
+        Ok(InterpolateExpr { column, expr })
+    }
+
     /// Parse a TOP clause, MSSQL equivalent of LIMIT,
     /// that follows after `SELECT [DISTINCT]`.
     pub fn parse_top(&mut self) -> Result<Top, ParserError> {