How many null values can be inserted in a coulmn whihc is unique constraint
Answers were Sorted based on User's Feedback
Answer / sumit
Any number of Null values can be inserted in such a column.
| Is This Answer Correct ? | 33 Yes | 7 No |
Answer / amit
Any no. of times you can insert null values in a coulmn
whihc is unique constraint because a Null value is
undefined,unassigned,and unapplicable value so thats why we
cannot compaire with any other null value or other value.
| Is This Answer Correct ? | 8 Yes | 2 No |
Answer / john bershan
any number of null value can be inserted into table for a
column which is declared as unique.coz null vale s either
not equal to any value or not equal to another null;
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / manish kumar
Single null Value
B'cse Unique Constraint contain unique value and single
null is also a unique value.
| Is This Answer Correct ? | 7 Yes | 29 No |
What is bind reference and how can it be created?
what is the difference between nested subquery and correlated subquery?
Are pl sql variables case sensitive?
How to handle bulk data?
How many sql databases can you have on one server?
Why should I use postgresql?
How do you take the union of two tables in sql?
What are the ways on commenting in a pl/sql code?
What is the use of sql trace?
What is a sql trace file?
What is having clause in sql?
Can any one tell me how to increase the performance of a sql query ie what are the performance tips in creating or writing a sql query !!?
Oracle (3259)
SQL Server (4518)
MS Access (429)
MySQL (1402)
Postgre (483)
Sybase (267)
DB Architecture (141)
DB Administration (291)
DB Development (113)
SQL PLSQL (3330)
MongoDB (502)
IBM Informix (50)
Neo4j (82)
InfluxDB (0)
Apache CouchDB (44)
Firebird (5)
Database Management (1411)
Databases AllOther (288)