Hi,
On 2015-03-01, 7:51 AM, "OC" wrote:
Hello there,
I'll need to copy thousands of objects from one table to another; the
copying'll be almost verbatim, but for a relationship. Namely,
entity OldAuction <->> OldRecord (relationships records->> and inverse
<-auction)
entity NewAuction <->> NewRecord (relationships records->> and inverse
<-newAuction)
Entity NewRecord has all attributes of OldRecord (and perhaps a couple of
others)
The naïve code would be something like
===
def orig=... an object of the OldAuction entity ...
def new=... an object of the NewAuction entity ...
orig.allRecords().each { OldRecord old ->
def
newRecord=EOUtilities.createAndInsertInstance(new.editingContext(),'NewRecord')
newRecord.newAuction=new
newRecord.takeValuesFromDictionary(old.valuesForKeys(old.attributeKeys()))
}
new.editingContext().saveChanges()
===
I'd do this in batches, say 200 - 1000 auctions and then save, dispose the EC,
create a new one and loop. That avoid any possible problems with too much
retained memory.
There's no need to make this lightning fast, e.g., a dedicated SQL procedure
would definitely be an overkill; but still, it should be as fast as possible
without making the code too complex, unintelligible and unmaintainable. I
wonder, what's the best way? Guess I might e.g., fetch rawrows for
orig.allRecords somehow, and use _them_ for the takeValuesFromDictionary
argument?
As long as you just want data values and not EOs for a relationship.
Chuck
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