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About the table record in the database.

Ian Su
Greenhorn

Joined: Nov 18, 2010
Posts: 25
I would like to know something like this.I have a specific record to delete from a table.When the delete operation is successful,it will delete the row with specific id(Primary key & auto_increment').
Eg.I have a table with 3 rows and These 3 records have id field filled with int data(auto_increment).That is 1,2,3.What I would like to do is when I delete the 2nd row and the 3rd row id will automatically reassigned to the above row id(the deleted row id).The 3rd row id will be 2 and like that.How to do it?Is it possible to make it like that?I need some advice from you all.Thank you very much.
Bosun Bello
Ranch Hand

Joined: Nov 06, 2000
Posts: 1510
What you are trying to do is recycle key values, and it's generally not advisable to attempt it. You just have to ignore the deleted primary key values. Primary autoincrement keys in database are used to uniquely identify a given row and should be used for just that. Do not apply any business meaning to it.


Bosun (SCJP, SCWCD)
So much trouble in the world -- Bob Marley
Ian Su
Greenhorn

Joined: Nov 18, 2010
Posts: 25
Thank you very much Bosun Bello for your advice!But I just want to know whether there is any keywords for recycle key values in sql or if I want to do it,I just have to correct each record manually?
Bear Bibeault
Author and ninkuma
Marshal

Joined: Jan 10, 2002
Posts: 61648
    
  67

Apparently you are having some trouble understanding Bosun's reply. I'll spell it out a bit more clearly: DON'T DO THAT!

What problem are you trying to solve with this approach?


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Ian Su
Greenhorn

Joined: Nov 18, 2010
Posts: 25
No, Bear.I understand and accept.I just want to know whether any sql keyword for this one has or not.No real world reason to do this.It is just my thought of doing this thing.If I want to do 'the key recycle values',I just have to manually do in the database or from the code right?No easy and straight way?Sorry I am just a beginner.
Thank you Bear & Bosun!
Bear Bibeault
Author and ninkuma
Marshal

Joined: Jan 10, 2002
Posts: 61648
    
  67

No, there isn't.
 
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