docs: private static String getDeleteLockSql() {
          if (deleteLockSql == null) {
              deleteLockSql =
                      "DELETE FROM "
                              + LOCK_TABLE
                              + " WHERE "
                              + ENTITY_TYPE_COLUMN
                              + EQ
                              + "?"
                              + " AND "
                              + ENTITY_KEY_COLUMN
                              + EQ
                              + "?"
                              + " AND "
                              + EXPIRATION_TIME_COLUMN
                              + EQ
                              + "?"
                              + " AND "
                              + LOCK_TYPE_COLUMN
                              + EQ
                              + "?"
                              + " AND "
                              + LOCK_OWNER_COLUMN
                              + EQ
                              + "?";
          }
          return deleteLockSql;
      }