- 其中report_hour的物化视图包含:date、timestamp、sum(times)
- ts_timezone_mapping 是个时区信息表,ttm_timestamp是该表的唯一键
【无法使用物化视图】查询场景:SELECT ttm_utc_0_date,SUM(times) AS times FROM report_hour LEFT JOIN ts_timezone_mapping ON timestamp = ttm_timestamp WHERE date=20241016 group by 1;
【explain提示的结果】:
TABLE: report.report_hour(report_hour), PREAGGREGATION: OFF. Reason: No aggregate on scan.
另外
【可以使用物化视图】查询场景:SELECT SUM(times) AS times FROM report_hour LEFT JOIN ts_timezone_mapping ON timestamp = ttm_timestamp WHERE date=20241016;