Mysql ORDER BY question...

monotiz · 2010-01-10 11:23:29

Hi, sorry for my bad english.

I have a question for Mysql and ORDER BY function.

I have 2 tables (TabA and TabB for example). In a TabA there is a column DateA with unix time data. In a TabB there is a column DateB with unix time data.

For example:

TabA
+------+---------+
| xxxA | DateA |
+------+---------+
| abc | 123 |
+------+---------+
| asd | 126 |
+------+---------+
| rsgf | 127 |
+------+---------+

TabB
+-------+---------+
| xxxB | DateB |
+-------+---------+
| try | 124 |
+-------+---------+

I would like to merge TabA and TabB and order the row by unix time. For example:

+------+-------+---------+----------+
| xxxA | xxxB | DateA | DateB |
+------+-------+---------+----------+
| abc | | 123 | |
+------+-------+---------+----------+
| | try | | 124 |
+------+-------+---------+----------+
| asd | | 126 | |
+------+-------+---------+----------+
| rsgf | | 127 | |
+------+-------+---------+----------+

Thanks.

samuele.mattiuzzo · 2010-01-10 12:24:19

SELECT * FROM tabA, tabB
ORDER BY tabA.dateA, tabB.dateB DESC

with merging i think you want to put all the tabs togheter without a particular condition, so you just simply cross them togheter

Ramses de Norre · 2010-01-10 12:27:52

samuele.mattiuzzo wrote:

SELECT * FROM tabA, tabB
ORDER BY tabA.dateA, tabB.dateB DESC

This will order them by dateA first and then by dateB, I think he wants them sorted on the union of the dates.

monotiz · 2010-01-10 12:32:40

Ramses de Norre wrote:

I think he wants them sorted on the union of the dates.

yes....

litemotiv · 2010-01-10 12:33:39

select bla from bla
union
select bla from bla2
order by bla

monotiz · 2010-01-10 12:40:25

litemotiv wrote:

select bla from bla
union
select bla from bla2
order by bla

But the 2 columns have different name....

litemotiv · 2010-01-10 12:58:07

monotiz wrote:

But the 2 columns have different name....

that's not a problem, each column you define in the select will be added to the result. you can combine columns to a single result but you don't have to:

http://www.mysqltutorial.org/sql-union-mysql.aspx

monotiz · 2010-01-10 13:10:33

litemotiv wrote:

monotiz wrote:
But the 2 columns have different name....
that's not a problem, each column you define in the select will be added to the result. you can combine columns to a single result but you don't have to:
http://www.mysqltutorial.org/sql-union-mysql.aspx

Ok thanks.. I try it...

samuele.mattiuzzo · 2010-01-10 13:15:49

since columns have different name but the same type, i think you can merge them into one only column and then order that one

Mandor · 2010-01-10 17:28:36

That would be a full (outer) join on the two timestamp columns, and after that order by the merged colums. But I'm not really sure about mysql capabilities...

Arch Linux

#1 2010-01-10 11:23:29

Mysql ORDER BY question...

#2 2010-01-10 12:24:19

Re: Mysql ORDER BY question...

#3 2010-01-10 12:27:52

Re: Mysql ORDER BY question...

#4 2010-01-10 12:32:40

Re: Mysql ORDER BY question...

#5 2010-01-10 12:33:39

Re: Mysql ORDER BY question...

#6 2010-01-10 12:40:25

Re: Mysql ORDER BY question...

#7 2010-01-10 12:58:07

Re: Mysql ORDER BY question...

#8 2010-01-10 13:10:33

Re: Mysql ORDER BY question...

#9 2010-01-10 13:15:49

Re: Mysql ORDER BY question...

#10 2010-01-10 17:28:36

Re: Mysql ORDER BY question...

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