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Hi
I hope this is the right forum for ths, if not, please direct me to the right one.
I looked at DAAB Ent LIb 2.0 January 2006 release. But I did not want to sprinkle the DAAB DLLs all over my different applications. Also, I wanted to de couple my dependency
on DAAB such that when a newer version comes and there are breaking changes, I can make
those changes only in the wrapper and not in all my projects.
Hence I wanted to create a wrapper on top of it.
I created a wrapper allright, my idea was that I would return data readers, datasets
and adapters from the wrapper. I would then use this wrapper in my app logic layer to get/set data.
However, as the reader requires an active connection, I could not pass it through layers.
Same for Command objects.
I could, however, pass the data table from the populated dataset.
Then I exposed a GetConnection method from the wrapper and returned the conn object.
I would then use it in App Logic layer to create a datareader etc.
However, this approach seems like a hack rather than an elegant solution.
Any ideas about how I can go about this?
Shreekar
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shreekar wrote: I would then use it in App Logic layer to create a datareader etc.
However, this approach seems like a hack rather than an elegant solution.
Any ideas about how I can go about this?
Data Readers, Connections and so on should stay in the DAL (Data Abstraction Layer - i.e. your wrapper). If you must, create data tables and data sets to pass data out of the DAL. It isn't something I'd do, but it is the easiest thing to do.
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Thanks a lot for your comments. I think I will settle with the datatable solution for now.
On a side note, I have read somewhere that the TableAdapter can be used as a replacement for DAAB. Currently, I am using TableAdapters in some forms of the application and after I resolved the connection string issue, it seems to work well. But I am not fully convinced about how well it will handle header-detail or multiple table relationships.
The way I see it, using the Table Adapters, I get strongly typed datasets which I will miss in DAAB, but in DAAB, I can design the App Logic Layer and sort of keep it separate from the DAL.
Before going the full distance with the DAAB/Table Adapters, I would like to know the pros and cons between using DAAB and Table Adapters.
Any thoughts on this?
Shreekar
http://shreekarishere.blogspot.com
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shreekar wrote: TableAdapter can be used as a replacement for DAAB
Do you mean DataAdapter?
shreekar wrote: Any thoughts on this?
I don't use DataAdapters at all. I find they don't give me the control that I want. They produce overly large and cumbersome DataSets with lots of functionality that I don't need. I use my own solution that dumps data in to Data Transfer Objects [DTOs] (basically a very simple class that contains nothing but fields and properties that relate directly to the columns being returned from the database). It is probably too much to explain in a forum post but I got the idea from the way DotNetNuke deals with the database (Search on DotNetNuke Data Provider for articles on how their implementation works). Each DTO is very lightweight, typesafe and can work with the DAAB.
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Well, I did mean TableAdapters - the new thing introduced with VS 2005 (not a part of .Net 2.0)
The mapping of fields and columns with the properties is the most natural mapping IMHO and the App Logic layer would have that ultimately in one form or another.
My question is - what is the better approach between such mapping and TableAdapters.
Shreekar
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Help me!
Thank you very much
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You can use typed datatypes.
fill then using sql server, and set the report source to them in your crystal report.
Steve
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Initialy i've taken the fileName and i want to take filename's contents the Datas.And i want to directly store in Access Database 2000
How to take the file's condents and one more thing i want to store the file's contents directly in AccessDatabase 2000.so pls some one help me.....
thanking You
somasundaram
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File.GetAllBytes, or something. Then, you need to create a field that can hold the data ( a BLOB? ) and push it in.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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I've put the code it won't the execute So pls some one help me vry vry Urgent
Thankig you
somasundaram
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What code ?
Are you using VB2005 ? Have you heard of google ? Why is it that so many people need urgently to know how to do something that's widely documented, but are unable to search for it ?
Christian Graus - C++ MVP
'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert
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Very sorry,no iam using VB.Net 2003, ok u carry on pls tel me....
I want to join in the website
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OK, then you don't have access to File.ReadAllBytes, I don't believe. The system.IO namespace contains the File object, which you'd use to read the bytes of a file. Then, you just need to google for soemthing like store bytes access VB.NET to get the second half together.
Christian Graus - C++ MVP
'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert
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Thank you
Thanking you
somasundaram
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Hello
using vs 2005
I have a datagridview and i would like to loop through and hide rows based on a cell condition. For example, if the user want to hide all the rows that has "Serviced" in the status column.
code so far
<br />
dim i as integer<br />
for i = 0 to ds.tables(0).rows.count - 1<br />
if(serviced = true) then<br />
'hide this row<br />
next i<br />
thanks in advance,
Steve
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Hi Steve
Simply make the RowHeight 0
Eldie
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Sir/Madam,
I am facing the problem in the query implementation in vb.net.Like I have an id that is present in 5 tables(like table1,table2,table3,table4,table5).I have to pick those records from table1 which are not present in tabl15.I mean an id number 1 is present in table1,table2,table3,table4 .but the id number 1 is not present in table5.My final motive is i have to pick all the id like 1.
i am using the query in the following way.
dim str as string = "Select able1.field1,table2.field1,table3.field1,table4.field1
from table1,table2,table3,table4,table5
where
(table1.id<>table5.id and table2.id <> table5.id and table3.id <> table5.id
and table4.id<> table5.id)
it is showing those records that are not present in table5 but present in the remaining tables.
But the problem is , there occured duplicacy.I mean one record is iterating 24 times i the final result.
Please help.
Thanks and Regards
Pankaj
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amaneet wrote: dim str as string = "Select able1.field1,table2.field1,table3.field1,table4.field1
from table1,table2,table3,table4,table5
where
(table1.id<>table5.id and table2.id <> table5.id and table3.id <> table5.id
and table4.id<> table5.id)
it is showing those records that are not present in table5 but present in the remaining tables.
But the problem is , there occured duplicacy.I mean one record is iterating 24 times i the final result.
Maybe you should look up the DISTINCT command and use it in your query.
HTH
Chandra
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Every time I press the enter key after updating the value in a textbox I hear a beep and no events are raised. I would like it to raise the 'leave' event so I can change it's color and transfer focus to an other object. I managed to do it by checking for "vbcr" in the "form keypress event" but is there a better way? Why isn't enter key working on my textboxes?
Hope that was clear as mud!!!! LOL
Rob
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You can use Textbox_presskey event. Such as
if keypress =13 then
textbox.background=......
textbox2.focus
end if
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Thanks, nerver noticed that the textbox had a keypress event too!!!! I stay up to late to program I guess..... LOL But it still doesn't solve my problem of why it beeps when I press enter instead of just updating the control.
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I have searched everywhere but can't find out how to do it. I am trying to create a multi-tabbed program and manage sub controls and content in it.
The program I'm designing is a multi-tabbed text editor, (like EditPad), and I want to manage the textbox inside of it so I can save and manipulate the text.
Is there an article on how to do this? I'm starting to think I'm in over head here. Would it be easier to do this in another language?
Thanks!
Trinity: Neo... nobody has ever done this before.
Neo: That's why it's going to work.
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How about a MDI application?
Tosch
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Thanks, but that's not what I'm looking for.
Any other ideas?
Trinity: Neo... nobody has ever done this before.
Neo: That's why it's going to work.
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