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SQL 23505

Posted on 2012-09-02
Medium Priority
Last Modified: 2013-08-07
I have an existing table, and the employee_id columns contain 0. So I decided to add a unique constraint to employee_id, but I got error SQL state: 23505. To solve this problem,  what should I do?
Question by:JavaTears
  • 2
LVL 38

Accepted Solution

Gerwin Jansen, EE MVE earned 800 total points
ID: 38361294
How nice of you to select 3 database types, please let us know which one this is about so we can help you better :)

But to help fix your issue, is there a difference between:

select count (employee_id) from your_table;


select distinct (employee_id) from your_table;

In case there is a difference then the constraint cannot be applied because you do not have unique values in your_table's employee_id field.
LVL 32

Assisted Solution

awking00 earned 800 total points
ID: 38363916
>>I have an existing table, and the employee_id columns contain 0.<<
The error is due to the fact that your employee_id column does not contain unique values (e.g. there are multiple 0's in the column), which are necessary to create a unique constraint. You would need to update the column so that the values are unique before adding the constraint. Which dbms are you actually using since that would determine how the update would need to be applied?
LVL 38

Expert Comment

by:Gerwin Jansen, EE MVE
ID: 38364150
@awking00 - I'm also suggesting that employee_id is not having unique values :D
LVL 23

Expert Comment

by:Steve Wales
ID: 39388564
This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.

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