如何將三句 mysql 查詢合并為一句？
原有三句查詢如下：
select count(*) as tp_count from `qra_works` where `created_time` > '2023-05-10 18:44:37' limit 1 select count(*) as tp_count from `qra_works` where `created_time` > '2023-05-10 18:44:37' and `version` = 'junior' limit 1 select count(*) as tp_count from `qra_works` where `created_time` > '2023-05-10 18:44:37' and `version` = 'senior' limit 1
這些查詢執行三次，影響效率。可以通過使用 group by 子句將它們合并為一句查詢：
SELECT version, COUNT(*) AS tp_count FROM `qra_works` WHERE `created_time` > '2023-05-10 18:44:37' GROUP BY version
此查詢將返回版本和相應數量，類似于原始查詢的結果。
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