Fix typo in comment.

MasaoFujii · MasaoFujii · commit 1804d1555f56 · 2016-07-25T17:51:26.000+09:00
Author: Masahiko Sawada
diff --git a/contrib/postgres_fdw/deparse.c b/contrib/postgres_fdw/deparse.c
@@ -1637,7 +1637,7 @@ deparseColumnRef(StringInfo buf, int varno, int varattno, PlannerInfo *root,
 
 		/*
 		 * In case the whole-row reference is under an outer join then it has
-		 * to go NULL whenver the rest of the row goes NULL. Deparsing a join
+		 * to go NULL whenever the rest of the row goes NULL. Deparsing a join
 		 * query would always involve multiple relations, thus qualify_col
 		 * would be true.
 		 */
