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I have a MandateFeature table that contains two Id's , MandateId and FeatureId. Each of these are foreign keys from two different tables (Feature and Mandate). If a mandate (house) contains 3 bedrooms and the Id for bedroom is 5, then the entries in the MandateFeature table will look something like this:
MandateId | FeatureId
----------------------
2, 5
2, 5
2, 5
If a mandate (house) has 2 bathrooms and the Id for bathroom is 6, then the table would look something like this:
MandateId | FeatureId
----------------------
2, 5
2, 5
2, 5
2, 6
2, 6
What I want to do, is to count the number of bedrooms as well as the number of bathrooms and then display it as follows:
Bedrooms: 3
Bathroom: 2
So I get it working using this:
SELECT DISTINCT dbo.__Mandate.Id, COUNT(BedroomFeature.FeatureId) AS Bedrooms, dbo.__MandateType.MandateType, dbo.__Mandate.ErfSize
FROM dbo.__Mandate INNER JOIN
dbo.__MandateType ON dbo.__Mandate.MandateTypeId = dbo.__MandateType.Id LEFT OUTER JOIN
dbo.__MandateListing ON dbo.__Mandate.Id = dbo.__MandateListing.MandateId LEFT OUTER JOIN
dbo.__MandateFeature AS BedroomFeature ON dbo.__Mandate.Id = BedroomFeature.MandateId AND BedroomFeature.FeatureId =
(SELECT Id
FROM dbo.__Feature AS __Feature_1
WHERE (Feature = 'Bedroom')) LEFT OUTER JOIN
dbo.__Feature ON BedroomFeature.FeatureId = dbo.__Feature.Id
GROUP BY dbo.__Mandate.Id, dbo.__MandateType.MandateType, dbo.__Mandate.ErfSize
..but this of course only displays the number of bedrooms. As soon as I duplicate this part:
LEFT OUTER JOIN
dbo.__MandateFeature AS BedroomFeature ON dbo.__Mandate.Id = BedroomFeature.MandateId AND BedroomFeature.FeatureId =
(SELECT Id
FROM dbo.__Feature AS __Feature_1
WHERE (Feature = 'Bedroom')) LEFT OUTER JOIN
dbo.__Feature ON BedroomFeature.FeatureId = dbo.__Feature.Id
and modify it to this:
LEFT OUTER JOIN
dbo.__MandateFeature AS BathroomFeature ON dbo.__Mandate.Id = BathroomFeature.MandateId AND BathroomFeature.FeatureId =
(SELECT Id
FROM dbo.__Feature AS __Feature_2
WHERE (Feature = 'Bathroom')) LEFT OUTER JOIN
dbo.__Feature AS __Feature_2 ON BathroomFeature.FeatureId = dbo.__Feature.Id
..and add COUNT(BathroomFeature.FeatureId) AS Bathrooms to the SELECT, it displays the bedrooms and bathrooms, but the values are duplicated across these 2 columns (and it's not the correct values either)
modified on Wednesday, April 20, 2011 5:49 AM
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Move your sub query from the join to the select and add the mandateID to the where clause. This can be repeated for different feature types.
Caveat this type of sub select can be very slow and expensive.
Another way would be to left join out to the feature table multiple times (1 for each feature type) using a case statement on the if field (case featureid when is null then 0 else 1 end), group by your mandate fields and sum each feature field.
Another way is to use the same multiple joins and then pivot the rows so each feature is in it's own column.
Never underestimate the power of human stupidity
RAH
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SELECT ID, PRODUCT, PRICE, QTY, PRICE*QTY AS TOTAL FROM PRODUCTS
I added the expression PRICE*QTY in the adapter select statement in the design time, now the values can't be updated when running the bound datagridview ie. loads but doesn't save changes.
Please help.
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Not really a surprise: if you were to edit TOTAL (so it no longer equals PRICE*QTY), what should the database do???
I would start by making the TOTAL column read-only. Not sure that will be sufficient though.
Luc Pattyn [Forum Guidelines] [My Articles] Nil Volentibus Arduum
Please use <PRE> tags for code snippets, they preserve indentation, improve readability, and make me actually look at the code.
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Thanks Luc,
Of course I'm not editing the totals and they're set to read only, I just need the user to see it as the values are entered.. The funny thing is that, I've done it before and I just don't seem to remember how..
Thanks mate!
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Mate you need to look into a proper data access layer. You are using the built in adaptors and running up against their limitations. The reason I didn't follow up on the last problem was I don't know, I and all good developers use and understand the DAL.
It's a learning thing but you obviously need to move to the next stage and get to know how your data is delivered, get to know stored procedures as well.
Never underestimate the power of human stupidity
RAH
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Thanks Holmes, you're absolutely right, actually, I never used the designer when it comes to database programming and this's exactly why I'm asking now.. Guess I'll just have to forget about the designer.. I thought if it will make my life easier, why not to go for it.
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I kicked off a Delete where value > 2 statement. I didn't expect it take take more than a couple of minutes, which has been the case for similar deletes on similar tables. But, it has been executing for 34 minutes, and when I run this statement, the status is suspended.
SELECT start_time, status, command FROM sys.dm_exec_requests
Any ideas as to how to check if or why the initial query is suspended or seemingly not running anymore.
Edit:
Using SQL '05, have seen some answers that suggest upgrading the SP2, but that is not an option right now.
Could this be related to lack of space on the drive where the tempdb and masterdb are stored and the OS is running?
Craigslist Troll: litaly@comcast.net
"I have a theory that the truth is never told during the nine-to-five hours. "
— Hunter S. Thompson
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Ok, it is a pageiolatch issue, lack of disk space.
Craigslist Troll: litaly@comcast.net
"I have a theory that the truth is never told during the nine-to-five hours. "
— Hunter S. Thompson
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Only a computer programmer would make a delete operation fail because there is not enough space. 
Chris Meech
I am Canadian. [heard in a local bar]
In theory there is no difference between theory and practice. In practice there is. [Yogi Berra]
posting about Crystal Reports here is like discussing gay marriage on a catholic church’s website.[Nishant Sivakumar]
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Ugh, I had too much faith in the admin. I moved the files for my Database to the E drive with enough space. He had a C drive as the OS drive with only 12 gig, and a D drive that was, from my understanding, supposed to be for programs, including SQL. The clown admin installed SQL to the system C drive with very limited space. It turns out the temp table and log files were getting full, jamming up the OS/SQL D: drive. I should say that this definitely is not my fault, as I don't remote to the machine ever, just use SQL Server Management Studio. So there was no way for me to be worried about it, or know about it even.
Craigslist Troll: litaly@comcast.net
"I have a theory that the truth is never told during the nine-to-five hours. "
— Hunter S. Thompson
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If you have a SP where you (among other things) need to extract the number of a certain rowtype, and you do this:
SELECT a, b, c, d, (SELECT COUNT(*) FROM table1 WHERE my_condition1=1) AS FooBarCount, e, f FROM table2 WHERE my_condition2=1;
it seems to me that the performance ought to be remarkably slower than if you do:
SELECT a, b, c, d, (SELECT COUNT(table1s_indexed_column) FROM table1 WHERE my_condition1=1) AS FooBarCount, e, f FROM table2 WHERE my_condition2=1;
At least according to everything I've learnt until now.
Can anybody confirm if I'm right or not?
Why can't I be applicable like John? - Me, April 2011
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Beidh ceol, caint agus craic againn - Seán Bán Breathnach
-----
Da mihi sis crustum Etruscum cum omnibus in eo!
-----
Everybody is ignorant, only on different subjects - Will Rogers, 1924
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It depends. But in general, I wouldn't expect so. But that's some weird code, there must be a better way.
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I can't answer your question with 100% certainty, but you should explore the SQL Profiler and run your queries through them to see what execution plan is choosen. Remember that just because an index exists, the optimizer may choose not to use it; resulting in a table scan.
Experiment with SQL Profiler and you can learn alot.
Good luck.
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I read somewhere[^] that the difference between count(*) and count(1) or count(indexed_column) is not nearly as relevant now as it used to be in the past. Basically, once the writers of the database engines learned of the problem, they quietly fixed it. The habit of writing count(1), however, outlived the bug. In the late nineties, using count(indexed_column) or count(1) would make queries a lot faster on many commercial engines (e.g. Oracle-7). At this point, however, most modern DB engines with the "non-toy" status should prefer count(*) to count(1).
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I don't know what the performance would be like but your code seems a bit weired. Does table1 and table2 have any relationship(column[s]) in common? it seems to be you're going to end up with a cartesian product of some sort.
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Hi,
I am getting the following error-
SQL> conn msdp/msdp
ERROR:
ORA-01033: ORACLE initialization or shutdown in progress
Warning: You are no longer connected to ORACLE.
Kindly help me what to do
Ish Kumar Kapila
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The “ORA-01033: ORACLE initialization or shutdown in progress.” error can also happen when Oracle is attempting startup or shutdown and is "hanging" on a resource such as a failed disk, writing to redo, etc.
Wait for few minutes and retry..
If after few tries it comes, restart your machine.
♫ 99 little bugs in the code,
99 bugs in the code
We fix a bug, compile it again
101 little bugs in the code ♫
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Hi,
Suppose I have this customer orders table in which we have to specify a customer for the new order, however, customers are most of the time the same so we just need to make it easier when creating the new order and list the customer name from the box.
I tried changing the datasource, value member and display member but it doesn't work.
Please help.
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I think you need to be more specific, cause your above scenario probably not indicate the actual issues.
Thanks
Md. Marufuzzaman
I will not say I have failed 1000 times; I will say that I have discovered 1000 ways that can cause failure – Thomas Edison.
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i have to import xml document having size more than 10GB in Sql Server database. i also have to do XSD Validation before Processing and maintain transaction. Please suggest me the best way to do the same. should i use SSIS packege? is it capable of Processing such large document? or Do i have to use c# coding to accomplish this task?
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you can do this using SSIS package. Please check this
♫ 99 little bugs in the code,
99 bugs in the code
We fix a bug, compile it again
101 little bugs in the code ♫
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Thanks for your Reply.
i apologize for reposting question in Asp.net and c#.
Would SSIS be capable for importing data from Large Xml Document(more than 10GB)?
did you try it?
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I suggest you proceed cautiously.
That is a big file and the vast majority of solutions deal with smaller files.
If it was me I think I would do the following
1. Create an app that does nothing but divide it into smaller files. Might not even do validation.
2. Create a second app that consumes the smaller files, validates, logs the file processed and then post to the database.
Advantages in the above.
1. If an error occurs you are going to need to manually review it. And reviewing a file that is 10/100 meg is easier than 10 gig.
2. If an error occurs you can manually fix and continue with the file that errored, rather than restarting everything.
3. You don't need to deal with the issue that the file is just too big for some part of the process.
Regardless however you must have the following features.
1. Log as you complete each block (insert, whatever) of work so you not only know where something failed but also can track that it succeeded.
2. Insure that transaction blocks are small. 1000 is probably a good number.
3. Design for the possibility that something will fail so you have a way to restart it at the failure point.
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