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Re: many-to-many query question

On 26/10/2007, at 12:47 PM, Chuck Hill wrote:

On Oct 25, 2007, at 6:29 PM, Lachlan Deck wrote:

On 26/10/2007, at 10:40 AM, James Cicenia wrote:

I have a many-to-many relationship as such:

Portfolio --->>MetricGroups--->>MetricItems<----project_item---- >Project

How I can create a query where

project can have ( Items(a) OR Items(b) ) AND (Items(c)) 

Something like this...

NSMutableArray itemsAQuals = new NSMutableArray();
String keyPathToA = "blah.blah";
for ( Item a : itemsA ) {
itemsAQuals.addObject( new EOKeyValueQualifier( keyPathToA, EOQualifier.QualifierOperatorContains, a ) );
}

etc...

EOQualifier q = new EOAndQualifier( new NSArray( new Object[] {
	new EOOrQualifier(new NSArray(new Object[] {
		new EOAndQualifier( itemsAQuals ),
		new EOAndQualifier( itemsBQuals )
	} ) ),
	new EOAndQualifier( itemsCQuals )
} ) );

That will work in memory, but EOQualifier.QualifierOperatorContains won't generate correct SQL for most databases.

News to me. Which databases do you think this affects? MySql is being used here...

Do you use one that this works on?

I've seen problems when not using 'contains' when crossing toMany boundaries rather than the opposite. I could paste various usages of QualifierOperatorContains <here> but are you suggesting that it your experience it doesn't work at all for db fetches or just across more complex relational boundaries as above?

with regards,
--

Lachlan Deck

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References: 
 >many-to-many query question (From: James Cicenia <email@hidden>)
 >Re: many-to-many query question (From: Lachlan Deck <email@hidden>)
 >Re: many-to-many query question (From: Chuck Hill <email@hidden>)



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