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Eddy Vluggen wrote: on the same terms that I do not check whether a file is
readonly/accesible/existing when I delete it
If I am coding file I/O I certainly do!
Never underestimate the power of human stupidity
RAH
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Again depending upon the database and how the constraint operation is implemented, there may also be performance gains by using the constraint instead of coding it into a program. But your mileage may vary extensively.
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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SayamiSuchi wrote: keyname ... inserted by user
Then why should it be unique?
If there's something that needs to be unique, then it should be created/set by the system not the user.
You already have id , what more do you need?
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PIEBALDconsult wrote: If there's something that needs to be unique, then it should be created/set by the system not the user
So next time you signup for an online service your username will be papsd9308skjfd9kdi32 .
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Yeah, pretty much, at least I won't have to waste a half hour trying things and trying things always having it tell me it exists.
Think of Animal House -- "Your name is Flounder. Your name is Pinto." Simple, saves the user a lot of needless trouble.
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Take a list of usernames. Usernames should be unique, but there's usually an identity. The identity is for the system, the username for the user.
Same goes for a filename; they need be unique, but you don't let the system choose it.
Bastard Programmer from Hell
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Eddy Vluggen wrote: filename; they need be unique
Not necessarily.
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Your new contract is located on the Z-share, and is called "contract.doc". Aw, there are two more files with the same name in there.
:z
Bastard Programmer from Hell
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That wouldn't be in the database, would it?
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That wouldn't matter, would it?
Some people generally check every option, others trust in a form of exception-handling.
Bastard Programmer from Hell
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Why does it matter to you? Do you make a difference between deleting a file from disk and a file from a database, from an exception-handling viewpoint?
It's a personal preference; lots of experienced programmers tend to check specific whether a file (or record) exists and whether they've got the appropriate rights to delete it (from disk or database). I prefer to rely on exception-handling, has always worked quite well for me.
Do you try-except, or do you return a customized boolean that consists of Yes , No and EFileNotFound ?
Bastard Programmer from Hell
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I'm pretty sure none of that has anything to do with the original question.
Eddy Vluggen wrote: a difference between deleting a file from disk and a file from a database
Yes. The database will likely return "0 records affected". The file system may simply say "ok, it's gone" even if it didn't exist. Either way, I don't care, just aslong as it's gone.
Eddy Vluggen wrote: whether they've got the appropriate rights to delete it
That's a case where looking first may give inacurate information and you could wind up having to handle an Exception anyway, so I prefer to just try it and see.
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PIEBALDconsult wrote: I'm pretty sure none of that has anything to do with the original question.
True.
Bastard Programmer from Hell
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Hello SayamiSuchi,
This problem can be solved in many ways.
Method 1: As has already been answered by UNCRushFan
IF NOT EXISTS (SELECT DISTINCT keyname FROM <table_name>)
BEGIN
INSERT INTO.....
END
Method 2: Another traditional way [ Count(ColumnName) approach ]
Declare @tblSource table([ID] int identity,[Name] varchar(20),[Key] varchar(10))
insert into @tblSource Select 'Sam', 'Sam1' Union all Select 'Joy','Joy2'
--Select * from @tblSource
Declare @key as varchar(10)
set @key = 'Joy2'
if(( Select count([KEY]) from @tblSource where [key] = @key) = 1)
begin
insert into @tblSource Select 'NewName', 'NewKey'
end
Select * from @tblSource
Method 3: Merge statement of Sql Server 2008
Consider the below statement first
Declare @tblSource table([ID] int identity,[Name] varchar(20),[Key] varchar(10))
insert into @tblSource Select 'Sam', 'Sam1' Union all Select 'Joy','Joy2'
Declare @tblDestination table([ID] int identity,[Name] varchar(20),[Key] varchar(10))
MERGE INTO @tblDestination AS Target
USING (SELECT [Name],[Key] FROM @tblSource) AS Source
ON Target.[Key] = Source.[Key]
WHEN NOT MATCHED BY TARGET THEN
INSERT (Name, [Key]) VALUES (Source.Name, Source.[Key]);
Select * from @tblDestination
I have a source table and a destination table. I am inserting the record in the destination table by checking whether the Key of the source table exists in the destination or not. In this case no key will be found in the destination and hence the output will be
ID Name Key
1 Sam Sam1
2 Joy Joy2
Now let us insert a record (with an already existing key) in the source table as
insert into @tblSource Select 'Joy','Joy2'
At this time the records in the source table will be
ID Name Key
1 Sam Sam1
2 Joy Joy2
3 Joy Joy2
Now if we run the above Merge statement query
MERGE INTO @tblDestination AS Target
USING (SELECT [Name],[Key] FROM @tblSource) AS Source
ON Target.[Key] = Source.[Key]
WHEN NOT MATCHED BY TARGET THEN
INSERT (Name, [Key]) VALUES (Source.Name, Source.[Key]);
Select * from @tblDestination
The output in the destination table will be
ID Name Key
1 Sam Sam1
2 Joy Joy2
because the key is already present in the destination table and hence it has been ignored.
But if we have the source table as
insert into @tblSource Select 'NewName','NewKey'
i.e.
ID Name Key
1 Sam Sam1
2 Joy Joy2
3 NewName NewKey
and then execute the above query, the output will be
ID Name Key
1 Sam Sam1
2 Joy Joy2
3 NewName NewKey
Because this time we are inserting a new key altogether.
So the query will be
MERGE INTO @tblDestination AS Target
USING (SELECT [Name],[Key] FROM @tblSource) AS Source
ON Target.[Key] = Source.[Key]
WHEN NOT MATCHED BY TARGET THEN
INSERT (Name, [Key]) VALUES (Source.Name, Source.[Key]);
N.B.~ This will work in Sql Server 2008 and above
Hope this helps
Thanks
Niladri Biswas
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I'm building a site that will be out on the web that takes job applications. Within the admin portal I am using SSRS 2008 to display the information from the database to the HR users. How do I need to set up SSRS so that I can point to the url that displays the report (I am rendering the report in a PDF format through the url)?
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You are going to have to set up an SSRS server if you want to use the URL method.
Never underestimate the power of human stupidity
RAH
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so, here is what I am doing so far: we have an SSRS server that is already up and running, so I put my report on that server so people in HR can get to the applications while at work. Now, we're dealing with multiple HR groups on different domains, so I want to place it on the web server so everyone can hit it but I am lost on how to configure SSRS to run on the run on the server. I can get it installed and up, but when I change the urls/virtual directories for SSRS it all goes to pot. What am I doing wrong?
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Hello CP,
I've got a package in Sql Server 2005 (Integrated Services) and had a question about the useage of parameters.
I perform a right click on my package and pick 'Run Package'.
I go to the Set Values tab and put in my parameters like this:
Property path | Value
\package.variables[Dir].Value | C:\DBExports\
\package.variables[Month].Value | 4
Here's my problem:
I want to use a single package to export the current and past month.
Is there a datetime function or macro I can call in the Value field?
The first rule of CListCtrl is you do not talk about CListCtrl - kornman
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Please can anyone assist me with the following questions?
1. Given the following table (the data could be hundreds of rows):
CompanyID CompanyName Town Country CompanySize
1 CompanyA Maryland USA 10
2 CompanyB Maryland USA 19
3 CompanyC Maryland USA 20
4 CompanyD Texas USA 13
5 CompanyE Texas USA 40
6 CompanyE Florida USA 4
For those towns which have more than one company in them, calculate (in one query):
· The total number of employees in the town.
· The average number of employees in a company (per town).
· The average number of employees in a company (per town) only for companies which
have less than 20 employees.
The results should exclude Florida and be sorted in descending order of the total number of
employees in the town.
I will be very grateful for your professional response.
Regards,
Current
Addendum
I forgot to mention that CompanySize is the number of employees
Thanks for your observation.
modified on Saturday, June 25, 2011 7:20 AM
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current1999 wrote: · The total number of employees in the town.
Based on this point, I can't see any employee information, I guess exists a Employee table which is related with your sample,right?
I Love T-SQL
"Don't torture yourself,let the life to do it for you."
If my post helps you kindly save my time by voting my post.
www.cacttus.com
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Hi Blue_Boy,
Did you see my addendum?CompanySize is the number of employees.
Cheers
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Look into using Group By Town and Sum(CompanySize) these will allow you to get the result you need. You may have yo do some filtering after the sum in which case look into Having sum() > #n
You weren't expecting someone to actually write the query for you were you!
Never underestimate the power of human stupidity
RAH
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Thanks.
Your propositions have been tested without success.
Since the sample data is given, if can supply full query, there is no sin!
Cheers
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If you need the code written for you then trundle across to rentacoder, we support people who want to learn how to write the code, NOT people who want us to do their work for them.
current1999 wrote: Your propositions have been tested without success.
Then show us what you have tried and we may be able to help you.
Never underestimate the power of human stupidity
RAH
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