Support UPDATE statements

Fix #10.

src/sqlast/mod.rs

@@ -471,6 +471,7 @@ impl ToString for SQLStatement {
             } => {
                 let mut s = format!("UPDATE {}", table_name.to_string());
                 if !assignments.is_empty() {
+                    s += " SET ";
                     s += &comma_separated_string(assignments);
                 }
                 if let Some(selection) = selection {
@@ -560,13 +561,13 @@ impl ToString for SQLObjectName {
 /// SQL assignment `foo = expr` as used in SQLUpdate
 #[derive(Debug, Clone, PartialEq)]
 pub struct SQLAssignment {
-    id: SQLIdent,
-    value: ASTNode,
+    pub id: SQLIdent,
+    pub value: ASTNode,
 }
 
 impl ToString for SQLAssignment {
     fn to_string(&self) -> String {
-        format!("SET {} = {}", self.id, self.value.to_string())
+        format!("{} = {}", self.id, self.value.to_string())
     }
 }
 

src/sqlparser.rs

@@ -117,6 +117,7 @@ impl Parser {
                     "DROP" => Ok(self.parse_drop()?),
                     "DELETE" => Ok(self.parse_delete()?),
                     "INSERT" => Ok(self.parse_insert()?),
+                    "UPDATE" => Ok(self.parse_update()?),
                     "ALTER" => Ok(self.parse_alter()?),
                     "COPY" => Ok(self.parse_copy()?),
                     _ => parser_err!(format!(
@@ -1606,6 +1607,31 @@ impl Parser {
         })
     }
 
+    pub fn parse_update(&mut self) -> Result<SQLStatement, ParserError> {
+        let table_name = self.parse_object_name()?;
+        self.expect_keyword("SET")?;
+        let mut assignments = vec![];
+        loop {
+            let id = self.parse_identifier()?;
+            self.expect_token(&Token::Eq)?;
+            let value = self.parse_expr()?;
+            assignments.push(SQLAssignment { id, value });
+            if !self.consume_token(&Token::Comma) {
+                break;
+            }
+        }
+        let selection = if self.parse_keyword("WHERE") {
+            Some(self.parse_expr()?)
+        } else {
+            None
+        };
+        Ok(SQLStatement::SQLUpdate {
+            table_name,
+            assignments,
+            selection,
+        })
+    }
+
     /// Parse a comma-delimited list of SQL expressions
     pub fn parse_expr_list(&mut self) -> Result<Vec<ASTNode>, ParserError> {
         let mut expr_list: Vec<ASTNode> = vec![];