Merge pull request #327 from matthias-Q/mysql_extract_functions

feat: parse mysql extract function

Author: DerekStride

grammar.js

@@ -2988,6 +2988,17 @@ module.exports = grammar({
               optional($.order_by)
             )
           ),
+          // https://dev.mysql.com/doc/refman/8.4/en/date-and-time-functions.html#function_extract
+          paren_list(
+            seq(
+              field(
+                'unit',
+                $.object_reference,
+              ),
+              $.keyword_from,
+              $.term
+            )
+          ),
           // _aggregate_function, e.g. group_concat
           wrapped_in_parenthesis(
             seq(

test/corpus/functions.txt

@@ -192,6 +192,58 @@ FROM table_a;
         (object_reference
           name: (identifier))))))
 
+================================================================================
+MYSQL period_diff
+================================================================================
+
+SELECT
+    PERIOD_DIFF (
+        EXTRACT (YEAR_MONTH FROM NOW()), EXTRACT(YEAR_MONTH FROM t.a)
+    ) AS diffA
+FROM mytable;
+
+--------------------------------------------------------------------------------
+
+(program
+  (statement
+    (select
+      (keyword_select)
+      (select_expression
+        (term
+          (invocation
+            (object_reference
+              (identifier))
+            (term
+              (invocation
+                (object_reference
+                  (identifier))
+                (object_reference
+                  (identifier))
+                (keyword_from)
+                (term
+                  (invocation
+                    (object_reference
+                      (identifier))))))
+            (term
+              (invocation
+                (object_reference
+                  (identifier))
+                (object_reference
+                  (identifier))
+                (keyword_from)
+                (term
+                  (field
+                    (object_reference
+                      (identifier))
+                    (identifier))))))
+          (keyword_as)
+          (identifier))))
+    (from
+      (keyword_from)
+      (relation
+        (object_reference
+          (identifier))))))
+
 ================================================================================
 GROUP CONCAT
 ================================================================================