Support create index with clause (#1389)

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

src/ast/dml.rs

@@ -45,6 +45,8 @@ pub struct CreateIndex {
     pub if_not_exists: bool,
     pub include: Vec<Ident>,
     pub nulls_distinct: Option<bool>,
+    /// WITH clause: <https://www.postgresql.org/docs/current/sql-createindex.html>
+    pub with: Vec<Expr>,
     pub predicate: Option<Expr>,
 }
 
@@ -83,6 +85,9 @@ impl Display for CreateIndex {
                 write!(f, " NULLS NOT DISTINCT")?;
             }
         }
+        if !self.with.is_empty() {
+            write!(f, " WITH ({})", display_comma_separated(&self.with))?;
+        }
         if let Some(predicate) = &self.predicate {
             write!(f, " WHERE {predicate}")?;
         }

src/dialect/generic.rs

@@ -86,4 +86,8 @@ impl Dialect for GenericDialect {
     fn allow_extract_single_quotes(&self) -> bool {
         true
     }
+
+    fn supports_create_index_with_clause(&self) -> bool {
+        true
+    }
 }

src/dialect/mod.rs

@@ -509,6 +509,12 @@ pub trait Dialect: Debug + Any {
     fn allow_extract_single_quotes(&self) -> bool {
         false
     }
+
+    /// Does the dialect support with clause in create index statement?
+    /// e.g. `CREATE INDEX idx ON t WITH (key = value, key2)`
+    fn supports_create_index_with_clause(&self) -> bool {
+        false
+    }
 }
 
 /// This represents the operators for which precedence must be defined

src/dialect/postgresql.rs

@@ -162,6 +162,10 @@ impl Dialect for PostgreSqlDialect {
     fn allow_extract_single_quotes(&self) -> bool {
         true
     }
+
+    fn supports_create_index_with_clause(&self) -> bool {
+        true
+    }
 }
 
 pub fn parse_comment(parser: &mut Parser) -> Result<Statement, ParserError> {

src/parser/mod.rs

@@ -5324,6 +5324,17 @@ impl<'a> Parser<'a> {
             None
         };
 
+        let with = if self.dialect.supports_create_index_with_clause()
+            && self.parse_keyword(Keyword::WITH)
+        {
+            self.expect_token(&Token::LParen)?;
+            let with_params = self.parse_comma_separated(Parser::parse_expr)?;
+            self.expect_token(&Token::RParen)?;
+            with_params
+        } else {
+            Vec::new()
+        };
+
         let predicate = if self.parse_keyword(Keyword::WHERE) {
             Some(self.parse_expr()?)
         } else {
@@ -5340,6 +5351,7 @@ impl<'a> Parser<'a> {
             if_not_exists,
             include,
             nulls_distinct,
+            with,
             predicate,
         }))
     }