Combine the result of multiple SQL select queries

Question

I have a table where I have fields as open_date and a close_date. I have to create a procedure for which, given a range of dates as input, I show all the records for each date that lies within the range, the records whose open_date>date and closed_date

for example if my table is

id   open_date    closed_date

1    2016-06-06   2016-06-10

2    2016-06-08   2016-06-11

and the range of dates is 2016-06-07 to 2016-06-09

then the result should be

Date          Count

2016-06-07      1

2016-06-08      2

2016-06-09      2

But the result that I am getting is

 Date          Count

2016-06-09      2

The procedure that I have written down is given below.

CREATE DEFINER=`root`@`localhost` PROCEDURE `find_number_of_bugs`(IN startDate DateTIme, IN endDate DateTime)

BEGIN

Declare testDate Date;

SET testDate=startDate;

while testDate<=endDate DO

select testDate as Dates ,count(bugID) as Number_Of_Bugs_Open from bugs where testDate between open_date and close_date OR close_date=null;

SET testDate=DATE_ADD(testDate,INTERVAL 1 DAY);

END while;

END

I guess I have to combine the results from the multiple select statements that
run throgh the while loop. Please suggest me a way to do that.

Answer 1

You are gutting all the results but in multiple result sets. You can save all query results in a temporary table and query it once at the end.

CREATE DEFINER=`root`@`localhost` PROCEDURE `find_number_of_bugs`(IN startDate DateTIme, IN endDate DateTime)
BEGIN
Declare testDate Date;
SET testDate=startDate;

CREATE TEMPORARY TABLE output (Dates date,Number_Of_Bugs_Open int);

while testDate<=endDate DO

insert into output select testDate as Dates ,count(bugID) as Number_Of_Bugs_Open from bugs where testDate between open_date and close_date OR close_date=null;

SET testDate=DATE_ADD(testDate,INTERVAL 1 DAY);
END while;

select * from output;

END

Combine the result of multiple SQL select queries

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