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karnataka
New User
Joined: 15 Sep 2006
Posts: 20
Location: bangalore
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Hi,
I am using cursor for deleting a record. Could you please tell me whats the use of "For UPdate" while declaring cursor in this case. Is this mandatory?
Thanks,
Jyothi |
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dick scherrer
Moderator Emeritus
Joined: 23 Nov 2006
Posts: 19244
Location: Inside the Matrix
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Hello,
Suggest that you are not using a cursor for deleting. . .
You are using a cursor for reading. Once a row is read (for update) it can be deleted. |
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karnataka
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Joined: 15 Sep 2006
Posts: 20
Location: bangalore
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Sorry.. Dick
Do you mean to say "FOR UPDATE" clause is not mandatory for cursor , incase if cursor is using for deleting record. |
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dick scherrer
Moderator Emeritus
Joined: 23 Nov 2006
Posts: 19244
Location: Inside the Matrix
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Hello,
| Quote: |
| Do you mean to say "FOR UPDATE" clause is not mandatory for cursor , incase if cursor is using for deleting record. |
Exactly the opposite. . .
In order to update/delete a fetched row, the row must be "held" - read FOR UPDATE.
One of the most basic concepts in every database system is that in order to update/delete data, the process must have control of that data (i.e. "held", "locked", etc). |
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GuyC
Senior Member
Joined: 11 Aug 2009
Posts: 1281
Location: Belgium
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| "for update" is not mandatory, but it helps to detect a read-only cursor you wish to use for update. |
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