pg_stat_get_bgwriter_timed_checkpoints() AS bg_checkpoint_time,
pg_stat_get_bgwriter_requested_checkpoints() AS bg_checkpoint_requested,
pg_stat_get_buf_written_backend() AS buffers_written,
pg_stat_get_buf_alloc() AS buffers_allocated
pg_stat_get_bgwriter_timed_checkpoints() AS bg_checkpoint_time,
pg_stat_get_bgwriter_requested_checkpoints() AS bg_checkpoint_requested,
pg_stat_get_buf_written_backend() AS buffers_written,
pg_stat_get_buf_alloc() AS buffers_allocated