Support TO in CREATE VIEW clause for Clickhouse (#1313)

Co-authored-by: Ifeanyi Ubah <ify1992@yahoo.com>
Co-authored-by: Andrew Lamb <andrew@nerdnetworks.org>

src/ast/mod.rs

@@ -2029,6 +2029,9 @@ pub enum Statement {
         if_not_exists: bool,
         /// if true, has SQLite `TEMP` or `TEMPORARY` clause <https://www.sqlite.org/lang_createview.html>
         temporary: bool,
+        /// if not None, has Clickhouse `TO` clause, specify the table into which to insert results
+        /// <https://clickhouse.com/docs/en/sql-reference/statements/create/view#materialized-view>
+        to: Option<ObjectName>,
     },
     /// ```sql
     /// CREATE TABLE
@@ -3329,15 +3332,20 @@ impl fmt::Display for Statement {
                 with_no_schema_binding,
                 if_not_exists,
                 temporary,
+                to,
             } => {
                 write!(
                     f,
-                    "CREATE {or_replace}{materialized}{temporary}VIEW {if_not_exists}{name}",
+                    "CREATE {or_replace}{materialized}{temporary}VIEW {if_not_exists}{name}{to}",
                     or_replace = if *or_replace { "OR REPLACE " } else { "" },
                     materialized = if *materialized { "MATERIALIZED " } else { "" },
                     name = name,
                     temporary = if *temporary { "TEMPORARY " } else { "" },
-                    if_not_exists = if *if_not_exists { "IF NOT EXISTS " } else { "" }
+                    if_not_exists = if *if_not_exists { "IF NOT EXISTS " } else { "" },
+                    to = to
+                        .as_ref()
+                        .map(|to| format!(" TO {to}"))
+                        .unwrap_or_default()
                 )?;
                 if let Some(comment) = comment {
                     write!(

src/parser/mod.rs

@@ -4172,6 +4172,14 @@ impl<'a> Parser<'a> {
             };
         }
 
+        let to = if dialect_of!(self is ClickHouseDialect | GenericDialect)
+            && self.parse_keyword(Keyword::TO)
+        {
+            Some(self.parse_object_name(false)?)
+        } else {
+            None
+        };
+
         let comment = if dialect_of!(self is SnowflakeDialect | GenericDialect)
             && self.parse_keyword(Keyword::COMMENT)
         {
@@ -4209,6 +4217,7 @@ impl<'a> Parser<'a> {
             with_no_schema_binding,
             if_not_exists,
             temporary,
+            to,
         })
     }
 

tests/sqlparser_bigquery.rs

@@ -315,6 +315,7 @@ fn parse_create_view_if_not_exists() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            ..
         } => {
             assert_eq!("mydataset.newview", name.to_string());
             assert_eq!(Vec::<ViewColumnDef>::new(), columns);

tests/sqlparser_clickhouse.rs

@@ -561,6 +561,21 @@ fn parse_select_star_except_no_parens() {
     );
 }
 
+#[test]
+fn parse_create_materialized_view() {
+    // example sql
+    // https://clickhouse.com/docs/en/guides/developer/cascading-materialized-views
+    let sql = concat!(
+        "CREATE MATERIALIZED VIEW analytics.monthly_aggregated_data_mv ",
+        "TO analytics.monthly_aggregated_data ",
+        "AS SELECT toDate(toStartOfMonth(event_time)) ",
+        "AS month, domain_name, sumState(count_views) ",
+        "AS sumCountViews FROM analytics.hourly_data ",
+        "GROUP BY domain_name, month"
+    );
+    clickhouse_and_generic().verified_stmt(sql);
+}
+
 fn clickhouse() -> TestedDialects {
     TestedDialects {
         dialects: vec![Box::new(ClickHouseDialect {})],

tests/sqlparser_common.rs

@@ -6279,6 +6279,7 @@ fn parse_create_view() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("myschema.myview", name.to_string());
             assert_eq!(Vec::<ViewColumnDef>::new(), columns);
@@ -6291,6 +6292,7 @@ fn parse_create_view() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(!temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }
@@ -6335,6 +6337,7 @@ fn parse_create_view_with_columns() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("v", name.to_string());
             assert_eq!(
@@ -6357,6 +6360,7 @@ fn parse_create_view_with_columns() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(!temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }
@@ -6378,6 +6382,7 @@ fn parse_create_view_temporary() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("myschema.myview", name.to_string());
             assert_eq!(Vec::<ViewColumnDef>::new(), columns);
@@ -6390,6 +6395,7 @@ fn parse_create_view_temporary() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }
@@ -6411,6 +6417,7 @@ fn parse_create_or_replace_view() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("v", name.to_string());
             assert_eq!(columns, vec![]);
@@ -6423,6 +6430,7 @@ fn parse_create_or_replace_view() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(!temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }
@@ -6448,6 +6456,7 @@ fn parse_create_or_replace_materialized_view() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("v", name.to_string());
             assert_eq!(columns, vec![]);
@@ -6460,6 +6469,7 @@ fn parse_create_or_replace_materialized_view() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(!temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }
@@ -6481,6 +6491,7 @@ fn parse_create_materialized_view() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("myschema.myview", name.to_string());
             assert_eq!(Vec::<ViewColumnDef>::new(), columns);
@@ -6493,6 +6504,7 @@ fn parse_create_materialized_view() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(!temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }
@@ -6514,6 +6526,7 @@ fn parse_create_materialized_view_with_cluster_by() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            to,
         } => {
             assert_eq!("myschema.myview", name.to_string());
             assert_eq!(Vec::<ViewColumnDef>::new(), columns);
@@ -6526,6 +6539,7 @@ fn parse_create_materialized_view_with_cluster_by() {
             assert!(!late_binding);
             assert!(!if_not_exists);
             assert!(!temporary);
+            assert!(to.is_none())
         }
         _ => unreachable!(),
     }

tests/sqlparser_snowflake.rs

@@ -552,6 +552,7 @@ fn parse_sf_create_or_replace_with_comment_for_snowflake() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            ..
         } => {
             assert_eq!("v", name.to_string());
             assert_eq!(columns, vec![]);

tests/sqlparser_sqlite.rs

@@ -171,6 +171,7 @@ fn parse_create_view_temporary_if_not_exists() {
             with_no_schema_binding: late_binding,
             if_not_exists,
             temporary,
+            ..
         } => {
             assert_eq!("myschema.myview", name.to_string());
             assert_eq!(Vec::<ViewColumnDef>::new(), columns);