mysql 求时间段平均值

while(iStartTime < iEndTime) do
-- 每次加一个小时
set vNextTime = date_add(iStartTime,interval 3600 second);
-- 单引号是特殊字符，要表示单引号，使用 ‘‘ 进行转义
set vSql = concat(vSql,‘union select 100, avg(`value`) from t1 where time between ‘‘‘,iStartTime,‘‘‘ and ‘‘‘, vNextTime,‘‘‘ ‘);
set iStartTime = vNextTime;
end while;

set vSql = substring(vSql,7);
-- 看看拼接的字符串是否正确
-- select vSql;

set @vSql = vSql;
prepare stmt from @vSql;
execute stmt;
deallocate prepare stmt;

END
;;
DELIMITER ;

mysql 求时间段平均值

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