Re: cached plan must not change result type

 forwarded to pgjdbc,  we want to understand why JDBC failed to reexecute the SQL instead of throw error out. Like this document https://jdbc.postgresql.org/documentation/server-prepare/#re-execution-of-failed-statements .

 

protected final void execute(CachedQuery cachedQuery,
      @Nullable ParameterList queryParameters, int flags)
      throws SQLException {
    try {
      executeInternal(cachedQuery, queryParameters, flags);
    } catch (SQLException e) {
      // Don't retry composite queries as it might get partially executed
      if (cachedQuery.query.getSubqueries() != null                                 <<< no idea how this  cachedQuery.query.getSubqueries() != null
          || !connection.getQueryExecutor().willHealOnRetry(e)) {
        throw e;
      }
      cachedQuery.query.close();
      // Execute the query one more time
      executeInternal(cachedQuery, queryParameters, flags);
    }
  }

cachedQuery.query.getSubqueries() != null, how this code decide composite queries  here ?   that mean some query having subquery or having many JOIN or LEFT JOINs like  select .... A left join B ...

Thanks,

James