Interested to Buy Any Domain ? << Click Here >> for more details...
what is unique key?
- 14 Answers
- 26936 Views
- Amazon, Cap Gemini, Infosys, Wipro, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / mapuka mueller
A unique key in sql signifies an attribute of an entity in a
table with the unique constraint, which simply implies that,
that a record(value) of that attribute can not be entered
more than once in that column (except null).
A further assignment of the primary key constraint to that
attribute (or a composite of two or more attributes(columns)
from values on the same row) makes it the unique identifier
of the record(row) in that table.
"It's sometimes hard to express what's in your mind but i
hope i tried"
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / shreekumar nair
unique key will only allow unique values in that particular column ...but it allows multiple NULL values ...since null values are not equal to an another null value...
whereas in a primary key column we can't have that ...
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / laya lombi
Is the key which is commonly call as password .
| Is This Answer Correct ? | 4 Yes | 14 No |
how many outer joins are used in a single sql query? is there any limitations for using of outer joins?
2 Answers BOB Technologies, Cap Gemini, IBM,
How to retrieve data from an cursor to a record?
Why do I get unexpected characters from 8-bit character sets in weblogic jdriver for oracle?
If a parameter is used in a query without being previously defined, what diff. exist betw. report 2.0 and 2.5 when the query is applied ?
How to lock and unlock a user account in oracle?
how to make an oracle object
What is the purpose of tables, private synonyms and public synonyms in Oracle?
ex. one table is having 1 column with 10 records , then how to display all the values in row wise ?
What is an oracle tablespace?
what is cartesian product?
How to create a server parameter file?
How can return max date row A b c d e 1 2 1-mar-09 5 10 1 2 10-mar-09 5 10 Only using oracle predefined function. Not user defined. Output:-- A b c d e 1 2 10-mar-09 5 10
Oracle General 
