Mysql – Select different dates from thesql

datetimeMySQL

I have a database structure like this

ID | title | startTime | endTime

And what I need is to get 3 records from the database where the first recorder is following this structure DAY(NOW())-1 the second record has to be like DAY(NOW()) or the first upcoming record and the third has to be like DAY(NOW())+1
What I was able to do is this:

SELECT DISTINCT title, FROM_UNIXTIME(startTime) as start FROM tl_calendar_events  
WHERE MONTH(FROM_UNIXTIME(startTime)) = MONTH(NOW()) 
AND DAY(FROM_UNIXTIME(startTime)) >= DAY(NOW()) 
ORDER BY DAY(FROM_UNIXTIME(startTime)) ASC LIMIT 3;

But this will return the first 3 upcoming records. The startTime and endTime are all unix timestamp fields. So the final output of this query would look something like this if I take that the date is: 06-12-2015:

Record #1 (startTime – 10-11-2015)
Record #2 (startTime – 06-12-2015)
Record #3 (startTime – 12-01-2016)

Also I need some sort of a DISTINCT select so that if it happens I have like 3 records with the on the same day I only select one. I figured I could do this with 3 joins but just ended up creating a lot of mess. I hope you understood my question and can provide some help.

SAMPLE DATA:

Event #1 (04-11-2015)
Event #2 (06-12-2015)
Event #3 (10-12-2015)
Event #4 (12-03-2016)
Event #5 (17-04-2016)

SAMPLE OUTPUT

EVENT #2 (as it is the first one before the current date)
EVENT #3 (as it is the current date or the first closest match)
EVENT #4 (as it is the first one to come after event #3)

I hope this will help explain my situation much better.

Best Answer

Please use yyyy-mm-dd to avoid confusion (mm-dd-yyyy vs dd-mm-yyyy) and be consistent with MySQL.

Does this give you the first item you want?

SELECT *
    FROM tbl
    WHERE ts < CURRENT_DATE()
    ORDER BY ts DESC
    LIMIT 1;

If so, does this give you the other two:

SELECT *
    FROM tbl
    WHERE ts > $foo
    ORDER BY ts
    LIMIT 2;

given that $foo is the timestamp you got from the first query.

I assume your ts is of datatype TIMESTAMP, not INT. DATETIME would also do.

If you need to display dd-mm-yyyy, use DATE_FORMAT in the SELECT, but not for internal calculations.

Common setup and sample data for all four methods

CREATE TABLE #example 
(
    id int NOT NULL DEFAULT '0',
    borrower_id int NOT NULL,
    started datetime NULL DEFAULT NULL,
    closed datetime NULL DEFAULT NULL,
    dead datetime NULL DEFAULT '0000-00-00 00:00:00'
);

CREATE TABLE #result 
(   
    borrower_id int NOT NULL DEFAULT '0',    
    started datetime NULL DEFAULT NULL,    
    ended datetime NULL DEFAULT NULL 
);    

INSERT INTO #example 
    (id, borrower_id, started, closed, dead) 
VALUES 
    (7714,238846,'2015-01-27 15:14:50','2015-02-02 14:14:13',NULL), 
    (7882,238846,'2015-01-28 13:25:58',NULL,'2015-05-15 12:16:07'), 
    (13190,259140,'2015-03-17 10:11:44',NULL,'2015-03-18 07:31:57'), 
    (13192,259140,'2015-03-17 10:12:17',NULL,'2015-03-18 11:46:46'), 
    (13194,259140,'2015-03-17 10:12:53',NULL,'2015-03-18 11:46:36'), 
    (14020,259140,'2015-03-23 14:32:16','2015-03-24 15:57:32',NULL), 
    (17124,242650,'2015-04-16 16:19:08','2015-04-16 16:21:06',NULL), 
    (19690,238846,'2015-05-15 13:17:31',NULL,'2015-05-27 13:56:43'), 
    (20038,242650,'2015-05-19 15:38:17',NULL,NULL), 
    (20040,242650,'2015-05-19 15:39:58',NULL,'2015-05-21 12:01:02'), 
    (20302,242650,'2015-05-21 13:09:06',NULL,NULL), 
    (20304,242650,'2015-05-21 13:09:54',NULL,NULL), 
    (20306,242650,'2015-05-21 13:10:19',NULL,NULL), 
    (20308,242650,'2015-05-21 13:12:20',NULL,NULL), 
    (21202,238846,'2015-05-29 16:47:29',NULL,NULL), 
    (21204,238846,'2015-05-29 16:47:56',NULL,NULL), 
    (21208,238846,'2015-05-29 17:05:15',NULL,NULL), 
    (21210,238846,'2015-05-29 17:05:55',NULL,NULL), 
    (21918,242650,'2015-06-04 17:04:29',NULL,'2015-06-12 15:47:23');

1. CASCADING - USING CLOSED RECORD solution

This is the solution I believe the asker is looking for & matches his results.

select *
into #temp1
from #example

while (select count(1) from #temp1)>0
begin
    --Grab only one user's records and place into a temp table to work with
    declare @curUser int
    set @curUser=(select min(borrower_id) from #temp1)

    select * 
    into #temp2
    from #temp1 t1
    where t1.borrower_id=@curUser

    while(select count(1) from #temp2)>0
    begin
        --Grab earliest start date and use as basis for 15 day window (#2 rule)
        --Use the record as basis for rules 3 and 4
        declare @minTime datetime
        set @minTime=(select min(started) from #temp2)

        declare @maxTime datetime
        set @maxTime=@minTime

        declare @curId int
        set @curId=(select min(id) from #temp2 where started=@minTime)

        select * 
        into #temp3
        from #temp2 t2
        where t2.id=@curId

        --Remove earliest record from pool of potential records to check rules against
        delete 
        from #temp2 
        where id=@curId

        --Insert all records within 15 days of start date, then remove record from pool
        while (select count(1) 
                from #temp2 t2 
                where t2.started<=DATEADD(day,15,@maxTime) 
                    or t2.closed<=DATEADD(day,15,@maxTime) 
                    or t2.dead<=DATEADD(day,15,@maxTime)  )>0
        begin
            insert into #temp3
            select *
            from #temp2 t2
            where t2.started<=DATEADD(day,15,@maxTime)  or t2.closed<=DATEADD(day,15,@maxTime)  or t2.dead<=DATEADD(day,15,@maxTime) 

            delete
            from #temp2
            where started<=DATEADD(day,15,@maxTime)  or closed<=DATEADD(day,15,@maxTime)  or dead<=DATEADD(day,15,@maxTime) 

            --set new max time from any column
            if (select max(started) from #temp3)>@maxTime
                set @maxTime=(select max(started) from #temp3)
            if (select max(closed) from #temp3)>@maxTime
                set @maxTime=(select max(started) from #temp3)
            if (select max(dead) from #temp3)>@maxTime
                set @maxTime=(select max(started) from #temp3)

        end

        --Calculate end time according to rule #3
        declare @end datetime 
        set @end = null
        set @end=(select min(closed) from #temp3)

        if @end is not null
        begin
            set @minTime=(select started from #temp3 where closed=@end)
        end

        if @end is null
        begin
            if(select count(1) from #temp3 where dead is null)=0
            set @end= (select max(dead) from #temp3)
        end

        insert into #result (borrower_id,started,ended)
        values (@curUser,@minTime,@end)

        drop table #temp3
    end

    --Done with the one user, remove him from temp table and iterate thru to the next user
    delete  
    from #temp1 
    where borrower_id=@curUser    

    drop table #temp2

end

drop table #temp1

drop table #example

select * from #result order by started

drop table #result

2. NON-CASCADING - USING CLOSED RECORD solution

Start calculated by first closed date when available, then by earliest start date.

select *
into #temp1
from #example

while (select count(1) from #temp1)>0
begin
    --Grab only one user's records and place into a temp table to work with
    declare @curUser int
    set @curUser=(select min(borrower_id) from #temp1)

    select * 
    into #temp2
    from #temp1 t1
    where t1.borrower_id=@curUser

    while(select count(1) from #temp2)>0
    begin
        --Grab earliest start date and use as basis for 15 day window (#2 rule)
        --Use the record as basis for rules 3 and 4
        declare @minTime datetime
        set @minTime=(select min(started) from #temp2)

        declare @curId int
        set @curId=(select min(id) from #temp2 where started=@minTime)

        select * 
        into #temp3
        from #temp2 t2
        where t2.id=@curId

        --Remove earliest record from pool of potential records to check rules against
        delete 
        from #temp2 
        where id=@curId

        --Insert all records within 15 days of start date, then remove record from pool
        insert into #temp3
        select *
        from #temp2 t2
        where t2.started<=DATEADD(day,15,@minTime)

        delete
        from #temp2
        where started<=DATEADD(day,15,@minTime)

        --Insert all records within 15 days of closed, then remove record from pool
        insert into #temp3
        select *
        from #temp2 t2
        where t2.closed<=DATEADD(day,15,@minTime)

        delete
        from #temp2
        where closed<=DATEADD(day,15,@minTime)

        --Insert all records within 15 days of dead, then remove record from pool
        insert into #temp3
        select *
        from #temp2 t2
        where t2.dead<=DATEADD(day,15,@minTime)

        delete
        from #temp2
        where dead<=DATEADD(day,15,@minTime)

        --Calculate end time according to rule #3
        declare @end datetime 
        set @end = null
        set @end=(select min(closed) from #temp3)

        if @end is not null
        begin
            set @minTime=(select started from #temp3 where closed=@end)
        end

        if @end is null
        begin
            if(select count(1) from #temp3 where dead is null)=0
            set @end= (select max(dead) from #temp3)
        end

        insert into #result (borrower_id,started,ended)
        values (@curUser,@minTime,@end)

        drop table #temp3
    end

    --Done with the one user, remove him from temp table and iterate thru to the next user
    delete  
    from #temp1 
    where borrower_id=@curUser


    drop table #temp2

end

drop table #temp1

drop table #example

select * from #result

drop table #result

3. NON-CASCADING - USING EARLIEST DATE solution

Start calculated by earliest date only.

select *
into #temp1
from #example

while (select count(1) from #temp1)>0
begin
    --Grab only one user's records and place into a temp table to work with
    declare @curUser int
    set @curUser=(select min(borrower_id) from #temp1)

    select * 
    into #temp2
    from #temp1 t1
    where t1.borrower_id=@curUser

    while(select count(1) from #temp2)>0
    begin
        --Grab earliest start date and use as basis for 15 day window (#2 rule)
        --Use the record as basis for rules 3 and 4
        declare @minTime datetime
        set @minTime=(select min(started) from #temp2)

        declare @curId int
        set @curId=(select min(id) from #temp2 where started=@minTime)

        select * 
        into #temp3
        from #temp2 t2
        where t2.id=@curId

        --Remove earliest record from pool of potential records to check rules against
        delete 
        from #temp2 
        where id=@curId

        --Insert all records within 15 days of start date, then remove record from pool
        insert into #temp3
        select *
        from #temp2 t2
        where t2.started<=DATEADD(day,15,@minTime) or t2.closed<=DATEADD(day,15,@minTime) or t2.dead<=DATEADD(day,15,@minTime)

        delete
        from #temp2
        where started<=DATEADD(day,15,@minTime) or closed<=DATEADD(day,15,@minTime) or dead<=DATEADD(day,15,@minTime)

        --Calculate end time according to rule #3
        declare @end datetime 
        set @end = null

        set @end=(select min(closed) from #temp3)

        if @end is null
        begin
            if(select count(1) from #temp3 where dead is null)=0
            set @end= (select max(dead) from #temp3)
        end

        insert into #result (borrower_id,started,ended)
        values (@curUser,@minTime,@end)

        drop table #temp3
    end

    --Done with the one user, remove him from temp table and itterate thru to the next user
    delete  
    from #temp1 
    where borrower_id=@curUser    

    drop table #temp2

end

drop table #temp1

drop table #example

select * from #result

drop table #result

4. CASCADING - USING EARLIEST DATE solution

Start calculated by earliest date only.

select *
into #temp1
from #example

while (select count(1) from #temp1)>0
begin
--Grab only one user's records and place into a temp table to work with
declare @curUser int
set @curUser=(select min(borrower_id) from #temp1)

select * 
into #temp2
from #temp1 t1
where t1.borrower_id=@curUser

while(select count(1) from #temp2)>0
begin
    --Grab earliest start date and use as basis for 15 day window (#2 rule)
    --Use the record as basis for rules 3 and 4
        declare @minTime datetime
    set @minTime=(select min(started) from #temp2)


    declare @maxTime datetime
    set @maxTime=@minTime

    declare @curId int
    set @curId=(select min(id) from #temp2 where started=@minTime)

    select * 
    into #temp3
    from #temp2 t2
    where t2.id=@curId

    --Remove earliest record from pool of potential records to check rules against
    delete 
    from #temp2 
    where id=@curId

    --Insert all records within 15 days of start date, then remove record from pool
    while (select count(1) 
            from #temp2 t2 
            where t2.started<=DATEADD(day,15,@maxTime) 
                or t2.closed<=DATEADD(day,15,@maxTime) 
                or t2.dead<=DATEADD(day,15,@maxTime)  )>0
    begin
        insert into #temp3
        select *
        from #temp2 t2
        where t2.started<=DATEADD(day,15,@maxTime)  or t2.closed<=DATEADD(day,15,@maxTime)  or t2.dead<=DATEADD(day,15,@maxTime) 

        delete
        from #temp2
        where started<=DATEADD(day,15,@maxTime)  or closed<=DATEADD(day,15,@maxTime)  or dead<=DATEADD(day,15,@maxTime) 

        --set new max time from any column
        if (select max(started) from #temp3)>@maxTime
            set @maxTime=(select max(started) from #temp3)
        if (select max(closed) from #temp3)>@maxTime
            set @maxTime=(select max(started) from #temp3)
        if (select max(dead) from #temp3)>@maxTime
            set @maxTime=(select max(started) from #temp3)

    end

    --Calculate end time according to rule #3
    declare @end datetime 
    set @end = null

    set @end=(select min(closed) from #temp3)

    if @end is null
    begin
        if(select count(1) from #temp3 where dead is null)=0
        set @end= (select max(dead) from #temp3)
    end

    insert into #result (borrower_id,started,ended)
    values (@curUser,@minTime,@end)

    drop table #temp3
end

--Done with the one user, remove him from temp table and iterate thru to the next user
delete  
from #temp1 
where borrower_id=@curUser

drop table #temp2

end

drop table #temp1

drop table #example

select * from #result order by started

drop table #result

Best Answer

Related Solutions

Sql-server – How to find XXth day of previous month in SQL server

Mysql – Query to determine start and end dates based on time overlap

Common setup and sample data for all four methods

1. CASCADING - USING CLOSED RECORD solution

2. NON-CASCADING - USING CLOSED RECORD solution

3. NON-CASCADING - USING EARLIEST DATE solution

4. CASCADING - USING EARLIEST DATE solution

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