Can a primary key have null values? If we try to insert a
null value in a primary key column, will it work or give an
error code?
- 6 Answers
- 20276 Views
- I also Faced
- E-Mail Answers
Answer Posted / ratheesh nellikal
In DB2 you can not create a primary key on a column which
is not 'not null'.
If you are trying to create a primary key on a column which
is not 'not null' then dbb2 will return an error like this
SQL0542N "feild_name" cannot be a column of a primary key
or unique key because it can contain null values.
SQLSTATE=42831
But once u alter the table and set the column to 'NOT NULL'
then you can make it as primary key.
Now if u r trying to insert an null value to ur primary key
column then db2 will trows an error like
SQL0407N Assignment of a NULL value to a NOT NULL
column "TBSPACEID=5, TABLEID=404, COLNO=0" is not allowed.
SQLSTATE=23502.
In short you can not make a column which can hold 'NULL'
value as your primary key and you can not insert a 'NULL'
value into your primary key feild.
Cheers,
Ratheesh Nellikal
| Is This Answer Correct ? | 7 Yes | 1 No |
Post New Answer View All Answers
Why do chiropractors use drop table?
My sql statement select avg(salary) from emp yields inaccurate results. Why?
Why select is not preferred in embedded sql programs?
Explain the benefits you can get from mainframe connect?
What is buffer pool and list some of them?
What is buffer pool in the db2 database?
What is meant by explain?
What is netezza database?
What is performance tuning db2?
What is a db2 package?
Is db2 a programming language?
Mention the different locking levels that are available in db2.
What is meant by dclgen?
When reorg is used?
What are the rules for db2 programming?
