diff --git a/src/wp-includes/class-wp-date-query.php b/src/wp-includes/class-wp-date-query.php
index 00a7554dea..cf3bddc9ae 100644
--- a/src/wp-includes/class-wp-date-query.php
+++ b/src/wp-includes/class-wp-date-query.php
@@ -473,6 +473,8 @@ class WP_Date_Query {
 	 *
 	 * @since 3.7.0
 	 *
+	 * @global wpdb $wpdb WordPress database abstraction object.
+	 *
 	 * @param string $column The user-supplied column name.
 	 * @return string A validated column name value.
 	 */
@@ -699,6 +701,8 @@ class WP_Date_Query {
 	 *
 	 * @since 4.1.0
 	 *
+	 * @global wpdb $wpdb WordPress database abstraction object.
+	 *
 	 * @param array $query        Date query clause.
 	 * @param array $parent_query Parent query of the current date query.
 	 * @return string[] {
@@ -961,6 +965,8 @@ class WP_Date_Query {
 	 *
 	 * @since 3.7.0
 	 *
+	 * @global wpdb $wpdb WordPress database abstraction object.
+	 *
 	 * @param string   $column  The column to query against. Needs to be pre-validated!
 	 * @param string   $compare The comparison operator. Needs to be pre-validated!
 	 * @param int|null $hour    Optional. An hour value (0-23).