Click here to Skip to main content
14,664,617 members
Home » Discussions » Database
   

Database

 
QuestionSybase query returns blank/empty for char fields Pin
Member 1354244115-Dec-17 6:56
MemberMember 1354244115-Dec-17 6:56 
AnswerRe: Sybase query returns blank/empty for char fields Pin
jschell16-Dec-17 9:06
Memberjschell16-Dec-17 9:06 
GeneralRe: Sybase query returns blank/empty for char fields Pin
Member 1354244117-Dec-17 1:33
MemberMember 1354244117-Dec-17 1:33 
GeneralRe: Sybase query returns blank/empty for char fields Pin
Member 1354244119-Dec-17 13:36
MemberMember 1354244119-Dec-17 13:36 
GeneralRe: Sybase query returns blank/empty for char fields Pin
Member 1354244121-Dec-17 14:09
MemberMember 1354244121-Dec-17 14:09 
QuestionNeed a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Schudi12-Dec-17 3:27
MemberSchudi12-Dec-17 3:27 
AnswerRe: Need a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Richard MacCutchan12-Dec-17 5:35
mveRichard MacCutchan12-Dec-17 5:35 
AnswerRe: Need a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Nathan Minier12-Dec-17 5:50
professionalNathan Minier12-Dec-17 5:50 
I think you have misunderstood a little how the three-tier model works.

You don't need to re-invent your model for each tier. There are different approaches on how to handle this, but most modern approaches are based on the Model-View-Something(MV*) architecture (MVC, MVVM, MVP...there seem to be new ones daily).

Each of these map to the three-tier architecture in slightly different ways, but there are consistent points. A Model is a an object that is solely a data container. It should implement no business logic, and in your case will represent a single record from the database. It's basically just a data container.

The other consistent element is the View, or UI. Any UI interaction logic should live here, to include wiring for UI event handlers and any UI-specific logic. This is where it can become easy to get lost and break the pattern, but play with it a little and you'll start to get it.

The last part of the MV* architecture is how the business layer is implemented. Ideally, the business layer should server as an intermediary between the DAL and the UI, and depending on implementation there can be a varying level of success with that.

I suggest you have a look around at some resources regarding these patterns; there is a lot available. Which one you start with depends a lot on what sort of applications you are writing: web apps almost invariably fall to the MVC side while Windows desktop apps generally end up in an MVVM world. Just don't let yourself get confused by MVC.NET, that's a specific implementation from MicroSoft.
"There are three kinds of lies: lies, damned lies and statistics."
- Benjamin Disraeli

GeneralRe: Need a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Schudi12-Dec-17 6:22
MemberSchudi12-Dec-17 6:22 
GeneralRe: Need a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Nathan Minier12-Dec-17 7:10
professionalNathan Minier12-Dec-17 7:10 
GeneralRe: Need a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Richard MacCutchan12-Dec-17 8:01
mveRichard MacCutchan12-Dec-17 8:01 
GeneralRe: Need a demo or tutorial of a simple SQL Database with a 3 Layer modell Pin
Schudi12-Dec-17 8:13
MemberSchudi12-Dec-17 8:13 
QuestionCTE Sub-Sort Pin
Stan Lake11-Dec-17 11:52
professionalStan Lake11-Dec-17 11:52 
AnswerRe: CTE Sub-Sort Pin
Richard Deeming12-Dec-17 1:56
mveRichard Deeming12-Dec-17 1:56 
GeneralRe: CTE Sub-Sort Pin
Stan Lake12-Dec-17 2:35
professionalStan Lake12-Dec-17 2:35 
GeneralRe: CTE Sub-Sort Pin
Mycroft Holmes12-Dec-17 12:45
professionalMycroft Holmes12-Dec-17 12:45 
QuestionTable Design Suggestion Pin
Manish K. Agarwal7-Dec-17 19:42
MemberManish K. Agarwal7-Dec-17 19:42 
AnswerRe: Table Design Suggestion Pin
Nathan Minier8-Dec-17 1:33
professionalNathan Minier8-Dec-17 1:33 
GeneralRe: Table Design Suggestion Pin
Manish K. Agarwal10-Dec-17 17:46
MemberManish K. Agarwal10-Dec-17 17:46 
GeneralRe: Table Design Suggestion Pin
Nathan Minier11-Dec-17 1:38
professionalNathan Minier11-Dec-17 1:38 
AnswerRe: Table Design Suggestion Pin
Richard Deeming8-Dec-17 1:35
mveRichard Deeming8-Dec-17 1:35 
GeneralRe: Table Design Suggestion Pin
Manish K. Agarwal10-Dec-17 17:53
MemberManish K. Agarwal10-Dec-17 17:53 
AnswerRe: Table Design Suggestion Pin
Mycroft Holmes9-Dec-17 0:00
professionalMycroft Holmes9-Dec-17 0:00 
QuestionCan the Pivot operator be used with text columns? Pin
Richard Andrew x646-Dec-17 4:14
professionalRichard Andrew x646-Dec-17 4:14 
AnswerRe: Can the Pivot operator be used with text columns? Pin
Richard Deeming6-Dec-17 9:51
mveRichard Deeming6-Dec-17 9:51 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.