How to Generate a List of Dates Between Two Dates in MySQL?
Generate a list of dates between two dates
To get a list of dates between two given dates, consider using a stored procedure like make_intervals
to create a temporary table time_intervals
filled with the required intervals. You can then join the data table with the time_intervals
table to get the desired output.
make_intervals
Stored Procedure (MySQL)
CREATE PROCEDURE make_intervals( startdate timestamp, enddate timestamp, intval integer, unitval varchar(10) ) BEGIN -- 初始化局部变量 declare thisDate timestamp; declare nextDate timestamp; set thisDate = startdate; -- 删除并创建用于区间的临时表 drop temporary table if exists time_intervals; create temporary table if not exists time_intervals( interval_start timestamp, interval_end timestamp ); -- 循环以递增并将区间插入到临时表中 repeat -- 根据单位和区间计算下一个区间日期 select case unitval when 'MICROSECOND' then timestampadd(MICROSECOND, intval, thisDate) when 'SECOND' then timestampadd(SECOND, intval, thisDate) when 'MINUTE' then timestampadd(MINUTE, intval, thisDate) when 'HOUR' then timestampadd(HOUR, intval, thisDate) when 'DAY' then timestampadd(DAY, intval, thisDate) when 'WEEK' then timestampadd(WEEK, intval, thisDate) when 'MONTH' then timestampadd(MONTH, intval, thisDate) when 'QUARTER' then timestampadd(QUARTER, intval, thisDate) when 'YEAR' then timestampadd(YEAR, intval, thisDate) end into nextDate; -- 将当前区间插入到临时表中 insert into time_intervals select thisDate, timestampadd(MICROSECOND, -1, nextDate); set thisDate = nextDate; -- 继续直到当前日期达到或超过结束日期 until thisDate >= enddate end repeat; END;
Usage examples
For example, to create a list of dates between January 1, 2009 and January 13, 2009, you would call the make_intervals
stored procedure as follows:
call make_intervals('2009-01-01 00:00:00', '2009-01-13 00:00:00', 1, 'DAY');
This will populate the time_intervals
table with intervals representing each day in the specified date range. You can then join the data table with the time_intervals
table to summarize the data based on these intervals.
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