I know that i can create a table without a primary key.But
is there any significance for that table???? while creating
an application.
Answers were Sorted based on User's Feedback
Answer / manikandan. s
Suppose if we have a situation like we need to store non
unique or null values in any of the column then we should
have table without primary key.
Is This Answer Correct ? | 5 Yes | 0 No |
Answer / archana.p
I feel that there is a significance for that table
too,Because there are situation in which we doesn't need to
identify unique records from that table
Is This Answer Correct ? | 3 Yes | 0 No |
Answer / yadu
I think table should have atleast one Primary key column as
it may be joined with any other tables to retrieve some
conditional inforamtion for the application in RDBMS.
Is This Answer Correct ? | 0 Yes | 0 No |
i thing we choose an application like null values and we
dont want any primary key to search an specific data.such
kinds of application used for small appln
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / amit
Definitely yes.....While creating a Data Warehouse
application,we need fact tables to be created from various
dimension tables and the fact table load type is always
INSERT not INSERT/UPDATE.Just think of a real world example
where the need is to populate all the daily transactional
data to a Data Warehouse for analytical purpose such as
creating reports and all.Suppose the DW is loaded two times
a day.In the first load,whatever the data present in the
Transactional Database is loaded into the DW.Before the
second load there might be some sort of updation made to
some of the records,so those records need to be inserted
into the DW again in the second load.If there would be
primary key in the fact table(i,e;DW),it will raise an error
(unique constraint violated.....).So,fact tables should not
contain any primary key.
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / nageswararao.k
yes we can create a table without primary key.How ever,using
not null,unique constraints.combine the both constraints
has primary key properties.so this is the table significance
Is This Answer Correct ? | 0 Yes | 0 No |
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