Is there an easy way to delete all rows not updated when done updating
a db?
On Jan 5, 2:15 pm, Me [email protected] wrote:
Is there an easy way to delete all rows not updated when done updating
a db?
What in the world do you mean?
Hard to answer a question without any details or context to what
you’re doing.
Jeff
purpleworkshops.com
I have a table of data that I update with a file. I would like to
delete all data that does not get updated.
How are you checking to see if the row was updated or not? By the
updated_at timestamp, or something else?
I’m not sure if you’re asking for help coming up with a way to determine
whether or not a row should be deleted, or just how to delete it.
The how to delete is simple enough, I guess. Just loop through the
records and call destroy on the object if it doesn’t meet your criteria
with something like this:
@records.each { |record| record.destroy if/unless # insert your logic
here }
– Josh
http://iammrjoshua.com
Me wrote:
I have a table of data that I update with a file. I would like to
delete all data that does not get updated.
Well that is the problem i need to find out which record have not been
updated so i can delete them. How do i do that?
On Jan 5, 3:50 pm, Joshua A. [email protected]
On Mon, Jan 5, 2009 at 12:32 PM, Me [email protected] wrote:
I have a table of data that I update with a file. I would like to
delete all data that does not get updated.
We’ve done stuff like this before. One pattern that we used was:
- At the beginning of the import process, we’d set a unique value
(like a timestamp/date) - We’d update an attribute in the table for all records with that
value:
example: last_import = 20081231
- then run your import/update process…
- then delete any records that last_import != 20081231
voila!
Robby
–
Robby R.
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