How Can I Efficiently Generate Dates in MySQL for Data Reporting Without Using Temporary Tables or Variables?

Efficient Date Generation for Data Reporting

In MySQL, generating a series of dates within a specified range is essential for creating comprehensive data reports. One common approach is to create a table filled with numerous dates, but this is not an efficient solution.

To address this issue, consider a scenario where creating temporary tables or setting variables is restricted. To generate dates within a specific period, such as the current year, the following MySQL query provides an effective solution:

select * from 
(select adddate('1970-01-01',t4*10000 + t3*1000 + t2*100 + t1*10 + t0) gen_date from
 (select 0 t0 union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t0,
 (select 0 t1 union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t1,
 (select 0 t2 union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t2,
 (select 0 t3 union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t3,
 (select 0 t4 union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t4) v
where gen_date between '2017-01-01' and '2017-12-31'

This query uses a nested series of subqueries that combine different values (0-9) to create dates from January 1, 1970, to December 31, 2017. The adddate() function is then used to shift these dates to the desired period.

By utilizing this approach, you can efficiently generate a series of dates for data reporting and analysis, without the need for temporary tables or variable assignment.

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