Re: SQL query Date Sort Problem - Database Discussion Boards

Re: SQL query Date Sort Problem

AnirbanM 23-Dec-12 19:12

AnirbanM 2

3-Dec-12 19:12

Thanks for varchar columns are not included in sorting.

Re: SQL query Date Sort Problem

PIEBALDconsult3-Dec-12 8:50

PIEBALDconsult

3-Dec-12 8:50

Always always always store date/time related values as DATE, DATETIME, etc.; never as string.

Re: SQL query Date Sort Problem

Mycroft Holmes3-Dec-12 13:12

Mycroft Holmes

3-Dec-12 13:12

His ToDate is stored as a Date type, first thing I looked for!

Never underestimate the power of human stupidity
RAH

Re: SQL query Date Sort Problem

PIEBALDconsult3-Dec-12 13:18

PIEBALDconsult

3-Dec-12 13:18

Sure, but Period isn't.

Re: SQL query Date Sort Problem

Mycroft Holmes3-Dec-12 16:18

Mycroft Holmes

3-Dec-12 16:18

And yet his OrderBy is Todate

Never underestimate the power of human stupidity
RAH

Re: SQL query Date Sort Problem

PIEBALDconsult3-Dec-12 17:29

PIEBALDconsult

3-Dec-12 17:29

Which is an all-you-can-eat sushi place -- very fishy indeed... Suspicious | :suss:

Re: SQL query Date Sort Problem

AnirbanM 23-Dec-12 18:57

AnirbanM 2

3-Dec-12 18:57

Thanks for your reply, however, i'm not getting your point, if i'm sorting based on date and other fields are characters, what's the problem? If anything there, i will surely change it.

Re: SQL query Date Sort Problem

AnirbanM 23-Dec-12 18:52

AnirbanM 2

3-Dec-12 18:52

Thanks, but sort is based on Date column only. As you rightly said, I always keep date as date column only. Month, Year, NoofDays etc, these columns are meant to be varchar, these are not included for sorting.

Re: SQL query Date Sort Problem

Mycroft Holmes3-Dec-12 16:24

Mycroft Holmes

3-Dec-12 16:24

There are a bunch of uglies in this table design
1. Storing numerics as character
2. Mixing varchar and nchar for no obvious reason
3. Using nchar instead of char (I would use varchar)
4. Using nchar instead of a bit (holiday)

Personally I think you should have only 3 fields in the table SNo,ToDate and Holiday. All the others should be calculated in a view!

Never underestimate the power of human stupidity
RAH

Re: SQL query Date Sort Problem

PIEBALDconsult3-Dec-12 17:28

PIEBALDconsult

3-Dec-12 17:28

10!

Re: SQL query Date Sort Problem

AnirbanM 23-Dec-12 19:07

AnirbanM 2

3-Dec-12 19:07

Thanks for your valuable feedback. I will change all nchar to varchar and holiday to bit. Moreover, I can safely remove Month and Date. But as you are suggesting, rest of the fields are calculative, then I need to make query then construct data table, make calculation and then put it into grid, otherwise, i'm simply getting all values from sql and putting straightaway into grid. So I made a trade off here, though it may not be the best way to do so.

Re: SQL query Date Sort Problem

AnirbanM 23-Dec-12 19:10

AnirbanM 2

3-Dec-12 19:10

What I can't understand and one of the puzzle is why SQL Server is not consistent and giving different results based on same query? Why out of 100 times, 97-98 times giving correct results and 1-2 times giving wrong.

Re: SQL query Date Sort Problem

Mycroft Holmes3-Dec-12 19:48

Mycroft Holmes

3-Dec-12 19:48

Please note I did not offer ANY help on that subject - it does not make any sense to me so I concentrated on the other areas hoping they may have an impact on your results.

To me a query cannot return inconsistent results!

Never underestimate the power of human stupidity
RAH

Re: SQL query Date Sort Problem

AnirbanM 24-Dec-12 2:12

AnirbanM 2

4-Dec-12 2:12

Yes, that's my core question. even if my table design is not good, even if SQL may internally converting date into float or even if i need to put 'ASC' after Order By, still question remains same. Why on earth SQL query is not consistent? Why not it's producing same results 100 out of 100 times? Is that means any internal bug in the SQL Server? Thanks.

Re: SQL query Date Sort Problem

AnirbanM 24-Dec-12 2:30

AnirbanM 2

4-Dec-12 2:30

Actually, based on the query results, within a loop creating new records and putting into a new SQL table 'Timesheet'. Now, when I see this new table 'Timesheet', it's rows are not created based on that sorting. For example, output of the query I got as 1/1/2012 to 1/31/2012 and now in the new table, inserting records like :
1/1/2012 - 51 - 12
1/2/2012 - 10 - 13
1/3/2012 - 15 - 20
..... till
1/31/2012 - 40 - 30

Now, sometimes (as I said earlier), it's creating rows in 'Timesheet' table that looks like:

1/12/2012 - 10 -20
1/13/2012 - 15-12
.. then
1/31/2012 - 40 - 30
..then
1/1/2012 - 51 - 12
1/2/2012 - 10 - 13
1/3/2012 - 15 - 20

It's not that all errors are starting from 1/12/2012, it can be 10th or 15th. So no possible pattern in these output which are giving error.

May be it will give more light into this matter. thanks.

Re: SQL query Date Sort Problem

Eddy Vluggen4-Dec-12 3:12

Eddy Vluggen

4-Dec-12 3:12

..and the table "timesheet" holds the day as a VARCHAR? That's not a bug, that's by design. Strings are sorted depending on the settings, should have been DATE type.

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]
They hate us for our freedom![^]

Re: SQL query Date Sort Problem

AnirbanM 24-Dec-12 3:27

AnirbanM 2

4-Dec-12 3:27

No sir, the sorting is made on 'ToDate' column which is of Date type, not varchar type, as I already given my column types before.

Re: SQL query Date Sort Problem

Eddy Vluggen4-Dec-12 4:44

Eddy Vluggen

4-Dec-12 4:44

AnirbanM 2 wrote:
No sir, the sorting is made on 'ToDate' column which is of Date type, not varchar type, as I already given my column types before.

Still, it sorts like it would be. Can you create a TSQL-script that reproduces the problem? Seems I can't, my dates keep returning ordered in a way that could be expected;

SQL

DECLARE @TEST TABLE (SD DATE);
INSERT INTO @TEST (SD) VALUES ('20010101');
INSERT INTO @TEST (SD) VALUES ('20011010');
INSERT INTO @TEST (SD) VALUES ('20010310');
INSERT INTO @TEST (SD) VALUES ('20010210');
INSERT INTO @TEST (SD) VALUES ('20010301');
INSERT INTO @TEST (SD) VALUES ('20010201');
SELECT * FROM @TEST ORDER BY SD;

Results:
2001-01-01
2001-02-01
2001-02-10
2001-03-01
2001-03-10
2001-10-10

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]
They hate us for our freedom![^]

Re: SQL query Date Sort Problem

Michael Potter4-Dec-12 8:11

Michael Potter

4-Dec-12 8:11

I would think the error is happening after the query is returned. Test the query in SQL alone and see if you get the error you describe.

Re: SQL query Date Sort Problem

jschell4-Dec-12 8:23

jschell

4-Dec-12 8:23

AnirbanM 2 wrote:
Please suggest where is the problem, thanks to all in advance.

Some posssible reasons.
- The problem originates from some other place in the code. So nothing to do with the code that you posted. And one very obvious possibility is that there is code somewhere that is sorting based on alphabetic ("10", "11" versus "1", "2) instead of using the sort that you gave.
- You are not looking at the actual data.
- You are not running the code that you think you are.

oltp vs olap

a.fatemeh2-Dec-12 10:51

a.fatemeh

2-Dec-12 10:51

hi every one

i'm not sure if it's true to brought my question here but I want to make clear how much Datawarehouse is useful for a company.what i want is a query example in sql which is long and hard for operational database and is a piece of cake for analytical database.
I've searched a lot but I can't fine one may be I searched wrongly but I would be so thanks full if any one could help me with this as soon as possible.

Re: oltp vs olap

Mycroft Holmes2-Dec-12 11:49

Mycroft Holmes

2-Dec-12 11:49

Instead of trying to find a "query" difference try researching the uses of the different types of database, a datawharehouse is a snapshot, usually delayed from real time, of the transaction (OLPT) database that is optimised for reporting (querying).

It is not an either/or question, once you reporting queries begin impacting on your transaction processing you need an OLAP solution as well as the OLTP.

This is a very simplistic view, there are entire libraries written on this subject!

Never underestimate the power of human stupidity
RAH

Re: oltp vs olap

a.fatemeh2-Dec-12 11:57

a.fatemeh

2-Dec-12 11:57

thanks so much,i almost know what you are talking about. but I really want a query .
this is a an extract from a book :"Although many decision-support queries can be written in SQL, others either
cannot be expressed in SQL or cannot be expressed easily in SQL."

I want an example of this kind of query which is written in both.

Re: oltp vs olap

Mycroft Holmes2-Dec-12 13:28

Mycroft Holmes

2-Dec-12 13:28

a.fatemeh wrote:
I want an example of this kind of query which is written in both.

Good luck with that, even if you could get the examples it would take a lot explaining to get the context of the requirement. You might want to look into the Microsoft example databases, they have various OLTP and OLAP dbs (AdventureWorks etc), there may be such comparative examples based on them but I doubt it.

Never underestimate the power of human stupidity
RAH

Re: oltp vs olap

a.fatemeh2-Dec-12 13:41

a.fatemeh

2-Dec-12 13:41

thanks by the way.
it seems I'd hardly find one.

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