feat: add athena unload statement

grammar.js

@@ -71,6 +71,7 @@ module.exports = grammar({
     keyword_truncate: _ => make_keyword("truncate"),
     keyword_merge: _ => make_keyword("merge"),
     keyword_show: _ => make_keyword("show"),
+    keyword_unload: _ => make_keyword("unload"),
     keyword_into: _ => make_keyword("into"),
     keyword_overwrite: _ => make_keyword("overwrite"),
     keyword_values: _ => make_keyword("values"),
@@ -744,10 +745,20 @@ module.exports = grammar({
           $._select_statement,
           $.set_operation,
           $._show_statement,
+          $._unload_statement,
         ),
       ),
     ),
 
+    // athena
+    _unload_statement: $ => seq(
+      $.keyword_unload,
+      wrapped_in_parenthesis($._select_statement),
+      $.keyword_to,
+      $._single_quote_string,
+      $.storage_parameters,
+    ),
+
     _show_statement: $ => seq(
       $.keyword_show,
       choice(
@@ -994,7 +1005,7 @@ module.exports = grammar({
     storage_parameters: $ => seq(
       $.keyword_with,
       paren_list(
-        seq($.identifier, optional(seq('=', $.literal))),
+        seq($.identifier, optional(seq('=', choice($.literal, $.array)))),
         true
       ),
     ),

queries/highlights.scm

@@ -111,6 +111,7 @@
   (keyword_delete)
   (keyword_create)
   (keyword_show)
+  (keyword_unload)
   (keyword_insert)
   (keyword_merge)
   (keyword_distinct)

test/corpus/unload.txt

@@ -0,0 +1,71 @@
+================================================================================
+Simple Unload
+================================================================================
+
+UNLOAD (SELECT * FROM old_table)
+TO 's3://amzn-s3-demo-bucket/unload_test_1/'
+WITH (format = 'JSON')
+
+--------------------------------------------------------------------------------
+
+(program
+  (statement
+    (keyword_unload)
+    (select
+      (keyword_select)
+      (select_expression
+        (term
+          (all_fields))))
+    (from
+      (keyword_from)
+      (relation
+        (object_reference
+          (identifier))))
+    (keyword_to)
+    (storage_parameters
+      (keyword_with)
+      (identifier)
+      (literal))))
+
+================================================================================
+Unload with ARRAY
+================================================================================
+
+UNLOAD (SELECT name1, address1, comment1, key1 FROM table1)
+TO 's3://amzn-s3-demo-bucket/ partitioned/'
+WITH (format = 'TEXTFILE', partitioned_by = ARRAY['key1'])
+
+--------------------------------------------------------------------------------
+
+(program
+  (statement
+    (keyword_unload)
+    (select
+      (keyword_select)
+      (select_expression
+        (term
+          (field
+            (identifier)))
+        (term
+          (field
+            (identifier)))
+        (term
+          (field
+            (identifier)))
+        (term
+          (field
+            (identifier)))))
+    (from
+      (keyword_from)
+      (relation
+        (object_reference
+          (identifier))))
+    (keyword_to)
+    (storage_parameters
+      (keyword_with)
+      (identifier)
+      (literal)
+      (identifier)
+      (array
+        (keyword_array)
+        (literal)))))