diff --git a/classes/data-stores/ActionScheduler_wpPostStore.php b/classes/data-stores/ActionScheduler_wpPostStore.php
index 8f6375a6..52103182 100644
--- a/classes/data-stores/ActionScheduler_wpPostStore.php
+++ b/classes/data-stores/ActionScheduler_wpPostStore.php
@@ -693,7 +693,16 @@ protected function claim_actions( $claim_id, $limit, ?DateTime $before_date = nu
 		$rows_affected = $wpdb->query( $wpdb->prepare( "{$update} {$where} {$order}", $params ) ); // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared, WordPress.DB.PreparedSQLPlaceholders.UnfinishedPrepare
 
 		if ( false === $rows_affected ) {
-			throw new RuntimeException( __( 'Unable to claim actions. Database error.', 'action-scheduler' ) );
+			$error = empty( $wpdb->last_error )
+				? _x( 'unknown', 'database error', 'action-scheduler' )
+				: $wpdb->last_error;
+			throw new \RuntimeException(
+				sprintf(
+					/* translators: %s database error. */
+					__( 'Unable to claim actions. Database error: %s.', 'action-scheduler' ),
+					$error
+				)
+			);
 		}
 
 		return (int) $rows_affected;