On Jul 11, 2006, at 9:23 AM, Randy Wigginton wrote:
I am getting a very strange error when I use my own EODelegate.
For management reasons I am required to use MySQL. The PK support
for MySQL out of the box for EOF is not thread safe; I can get
duplicate IDs. Thus, I've created a very simple delegate, which
looks like this:
public myEODelegate() {
EODatabaseContext.setDefaultDelegate(this);
}
private static NSArray keys = new NSArray("pk");
public NSDictionary databaseContextNewPrimaryKey(EODatabaseContext
dbCtxt, Object object, EOEntity entity) {
NSArray keyNames = entity.primaryKeyAttributeNames();
if (keyNames.size()!=1)
return null;
String pkName = (String)keyNames.get(0);
try {
EOEditingContext ec = new EOEditingContext();
NSArray rawRows = EOUtilities.rawRowsForSQL(ec, "testit",
"UPDATE EO_PK_TABLE SET pk=pk+1 where lower(name)
='"+entity.externalName().toLowerCase()+"'");
rawRows = EOUtilities.rawRowsForSQL(ec, "testit", "select pk
from eo_pk_table where lower(name)='"+entity.externalName
().toLowerCase()+"'", keys);
That may be better than the default MySQL stuff, but you still have a
race condition there. You need to do this in the context of a
transaction.
NSDictionary foo = (NSDictionary)rawRows.get(0);
Long bd = (Long)foo.valueForKey("pk");
I suspect that this is your problem. Looking below, it seems that
EOF is expecting an Integer.
return new NSDictionary(bd, pkName);
} catch (Exception e) { // Use default delegate
return null;
}
}
The problem is this. I have a relationship, Owner and subguy.
Owner has a primary key; subguy is owned by Owner. In the
relationship, Owner propagates the primary key and owns the
destination. Here is some code that will always fail:
allDelegate = new myEODelegate(); // turn on my delegate
EOEditingContext ec = new EOEditingContext();
NSLog.allowDebugLoggingForGroups(0x10000L);
Owner own =
(Owner)EOUtilities.createAndInsertInstance(ec,"owner");
Subguy gag = aag.sub();
gag.setGoogleID(new Integer(1001));
ec.saveChanges();
gag.setContentBid(new Double(1.01));
ec.saveChanges();
What is VERY strange is that if I delete the first saveChanges(),
everything works. With it there, I get an exception:
<main> A fatal exception occurred: cannot update primary-key
'adGroupID' from '13' to '13' on object:{values = {googleID = 1001;
contentBid = 1.01; adGroupID = 13; }; this = "<Subguy 8a3fe6
_EOIntegralKeyGlobalID[subguy (java.lang.Integer)13]>"; } of
entity: subguy in databaseContext
[EMAIL PROTECTED]
Notice that this says _EOIntegralKeyGlobalID[subguy
(java.lang.Integer)13] while your delegate returns a Long. The real
message should probably be cannot update primary-key 'adGroupID' from
'(java.lang.Integer)13]' to '(java.lang.Long)13]'.
Do the PK columns in the model have a Value Type of l (that is an L)?
What happens if you convert the Long to an Integer in your delegate
method?
Chuck
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