"1 warning" but nothing in output


#1

Hi -

When I run explain statements, sometimes in the MemSQL CLI it says “1 warning” but there’s nothing in the output. For example, this was the recent output from an explain statement:

+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| EXPLAIN                                                                                                                                                                                                                                                                                                                                   |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Project [value, remote_0.epoch, remote_0.metric, remote_0.app_group_id]                                                                                                                                                                                                                                                                   |
| HashGroupBy [SUM(remote_0.value) AS value] groups:[remote_0.op, remote_0.metric, remote_0.app_group_id]                                                                                                                                                                                                                                   |
| Gather partitions:all alias:remote_0                                                                                                                                                                                                                                                                                                      |
| Project [value, UNIX_TIMESTAMP(CONVERT_TZ(TIME_FORMAT(CONVERT_TZ(FROM_UNIXTIME(f.epoch),'SYSTEM','+00:00'),'%Y-%m-%d'),'+00:00','SYSTEM')) AS epoch, dim_metrics_ref.metric, dim_apps_ref.app_group_id, UNIX_TIMESTAMP(CONVERT_TZ(TIME_FORMAT(CONVERT_TZ(FROM_UNIXTIME(f.epoch),'SYSTEM','+00:00'),'%Y-%m-%d'),'+00:00','SYSTEM')) AS op] |
| HashGroupBy [SUM(f.value) AS value] groups:[UNIX_TIMESTAMP(CONVERT_TZ(TIME_FORMAT(CONVERT_TZ(FROM_UNIXTIME(f.epoch),'SYSTEM','+00:00'),'%Y-%m-%d'),'+00:00','SYSTEM')), dim_metrics_ref.metric, dim_apps_ref.app_group_id]                                                                                                                |
| HashJoin [f.app_id = dim_apps_ref.id]                                                                                                                                                                                                                                                                                                     |
| |---Project [dim_apps_ref_0.app_group_id, dim_apps_ref_0.id] est_rows:3 alias:dim_apps_ref                                                                                                                                                                                                                                                |
| |   IndexRangeScan report_service.dim_apps_ref AS dim_apps_ref_0, KEY dim_apps_ref_partner_id_idx (partner_id) scan:[partner_id IN (...)] est_table_rows:276,800 est_filtered:4                                                                                                                                                           |
| HashJoin [f.metric_id = dim_metrics_ref.id]                                                                                                                                                                                                                                                                                               |
| |---Project [dim_metrics_ref_0.metric, dim_metrics_ref_0.id] est_rows:35 alias:dim_metrics_ref                                                                                                                                                                                                                                            |
| |   IndexSeek report_service.dim_metrics_ref AS dim_metrics_ref_0, UNIQUE KEY dim_metrics_metric_key (metric) scan:[metric IN (...)] est_table_rows:138 est_filtered:35                                                                                                                                                                   |
| Filter [f.epoch IN (...)]                                                                                                                                                                                                                                                                                                                 |
| BloomFilter table:dim_apps_ref fields:f.app_id                                                                                                                                                                                                                                                                                            |
| BloomFilter table:dim_metrics_ref fields:f.metric_id                                                                                                                                                                                                                                                                                      |
| ColumnStoreScan report_service.facts_app_metrics_staging AS f, KEY epoch (epoch, app_id, metric_id, device_country_id, store_id) USING CLUSTERED COLUMNSTORE WITH(COLUMNSTORE_SEGMENT_ROWS=1024000, COLUMNSTORE_FLUSH_BYTES=2097152) est_table_rows:97,720,011 est_filtered:97,720,011                                                    |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
15 rows in set, 1 warning (0.12 sec)

Any idea what could cause this?


#2

Can you include a repro?


#3

If you run show warnings after the query that created the warning it will display the warning.


#4

Thanks rob! The show warnings command did the trick – didn’t realize that one. I suspect what was happening was that there was a warning about the sql I was explaining rather than a warn from the explain about something like an ANALYZE command needing to be run.