Unique Predicate
Wed, 03/04/2009 - 20:02 | 
hdanzl
Specify a test for the absence of duplicate rows.
Syntax
<unique predicate> ::= UNIQUE <table subquery>
Notes
| ♦ | The predicate evaluates to TRUE if the subquery result is empty or it contains no duplicate rows, else to FALSE. |
Examples
| 1) | The following example selects students enrolled in none or only 1 course: |
SELECT studentID, studentName
FROM students s
WHERE UNIQUE (
SELECT studentID
FROM enrolls
WHERE studentID = s.studentID
)
Conformance
|
SQL:2003 standard |
- |
Feature F291 "UNIQUE predicate" |
Tags:
Questions? Problems?
- Interested to buy but something put you off?
- Can't find what you're looking for?
- Have a suggestion?
Let us know. If you're having trouble contacting us, please check here.
![[]](/support/modules/ubercart/uc_cart/images/bullet-arrow-up.gif "Expand cart block."){kind=icon}
| 1x | NexusDB AWE DLL (10 installations; binary) | AUD 1,950.00 |
| 1x | SLA - Gold (add years in quantity field) | AUD 3,600.00 |
| 1x | NexusDB Developer DCU Edition | AUD 600.00 |
| 1x | NexusDB AWE DLL (40 installations; binary) | AUD 6,400.00 |
| 1x | NexusDB PHP Connector | AUD 500.00 |
| 1x | NexusDB AWE DLL (100 installations; binary) | AUD 12,500.00 |
| 6 Items | Total: AUD 25,550.00 |
| (View cart) (Checkout) | |
Site Updates
- Dec 4 2024 - 1:53pm
- Dec 4 2024 - 1:48pm
- Nov 19 2024 - 1:04pm
- Oct 17 2024 - 10:27am
- Jul 24 2024 - 1:22pm