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AnswerRe: Please Help to me this is very urgent issue Pin
kubben12-Oct-07 2:13
kubben12-Oct-07 2:13 
AnswerRe: Please Help to me this is very urgent issue Pin
Skanless12-Oct-07 5:35
Skanless12-Oct-07 5:35 
Questionconnection string Pin
IamAmit11-Oct-07 5:49
IamAmit11-Oct-07 5:49 
AnswerRe: connection string Pin
Vasudevan Deepak Kumar11-Oct-07 7:24
Vasudevan Deepak Kumar11-Oct-07 7:24 
Question1:1 Relationships Pin
Brendan Vogt11-Oct-07 4:43
Brendan Vogt11-Oct-07 4:43 
AnswerRe: 1:1 Relationships Pin
John Gathogo11-Oct-07 4:47
John Gathogo11-Oct-07 4:47 
AnswerRe: 1:1 Relationships Pin
Rob Philpott11-Oct-07 4:54
Rob Philpott11-Oct-07 4:54 
GeneralRe: 1:1 Relationships Pin
Colin Angus Mackay11-Oct-07 5:22
Colin Angus Mackay11-Oct-07 5:22 
Rob Philpott wrote:
A one-to-one relationship doesn't make much sense as you may as well combine the tables into one. I'm not sure you can even create such a relationship because you'd have to simultaneously insert into both tables in order not to break the constraint. Anyone?


1-to-1 relationships can make sense in some circumstances when dealing with optimisation of very large rows, especially if some of the columns are only very rarely neaded. It is also useful when dealing with joining separately maintained systems that need to keep in sync (e.g. if you buy in a third party system and want to extend it without touching its database tables)

Typically it would actually be a zero-to-one because you insert one row then they other.

Parent
------
ID PK
Col1
Col2
Col3

Child
-----
ID PK FK
Col4
Col5
Col6

The Child row is optional, but there can be only one as its primary key is also the foreign key (which forces the oneness of the relationship)


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AnswerRe: 1:1 Relationships Pin
Skanless12-Oct-07 5:38
Skanless12-Oct-07 5:38 
GeneralRe: 1:1 Relationships Pin
Colin Angus Mackay12-Oct-07 9:03
Colin Angus Mackay12-Oct-07 9:03 
QuestionTable comparison in sql server 2000 Pin
Guru_yogi11-Oct-07 4:10
Guru_yogi11-Oct-07 4:10 
AnswerRe: Table comparison in sql server 2000 Pin
Rob Philpott11-Oct-07 4:37
Rob Philpott11-Oct-07 4:37 
AnswerRe: Table comparison in sql server 2000 Pin
John Gathogo11-Oct-07 4:44
John Gathogo11-Oct-07 4:44 
AnswerRe: Table comparison in sql server 2000 Pin
Hesham Amin12-Oct-07 8:41
Hesham Amin12-Oct-07 8:41 
Questionvarchar and nvarchar Pin
Brendan Vogt11-Oct-07 3:55
Brendan Vogt11-Oct-07 3:55 
AnswerRe: varchar and nvarchar Pin
Rob Philpott11-Oct-07 4:35
Rob Philpott11-Oct-07 4:35 
GeneralRe: varchar and nvarchar Pin
Mark Churchill11-Oct-07 17:48
Mark Churchill11-Oct-07 17:48 
QuestionPerformance issue Pin
Albu Marius11-Oct-07 3:35
Albu Marius11-Oct-07 3:35 
AnswerRe: Performance issue Pin
Colin Angus Mackay11-Oct-07 3:43
Colin Angus Mackay11-Oct-07 3:43 
GeneralRe: Performance issue Pin
Albu Marius11-Oct-07 4:34
Albu Marius11-Oct-07 4:34 
GeneralRe: Performance issue Pin
Colin Angus Mackay11-Oct-07 5:35
Colin Angus Mackay11-Oct-07 5:35 
GeneralRe: Performance issue Pin
Albu Marius11-Oct-07 6:31
Albu Marius11-Oct-07 6:31 
Questionhow to block ? Pin
ahmed eldeghedy11-Oct-07 2:58
professionalahmed eldeghedy11-Oct-07 2:58 
AnswerRe: how to block ? Pin
Colin Angus Mackay11-Oct-07 3:42
Colin Angus Mackay11-Oct-07 3:42 
GeneralRe: how to block ? Pin
Paul Conrad12-Oct-07 12:04
professionalPaul Conrad12-Oct-07 12:04 

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