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MongoDB and “joins” [duplicate]
...ll only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are ...
Get spinner selected items text?
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I used the code and the result is not what I need on the debuging mode I found the it gives me a value like {supliers=VITA}. but I only need the value "VITA" any ideas?
– Pedro Teran
Mar 1 '12 at 21:07
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Add new item count to icon on button - Android
...tems under tabs. What I KNOW how to do - is create new icons with red dots and just display them when new stuff available.
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Print Current Mercurial Revision Hash?
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No prob. hg help revisions and hg help revsets has some crazy powerful shortcuts like that.
– Ry4an Brase
Jun 13 '12 at 20:47
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How to implement a unique index on two columns in rails
I have a table and I'm trying to add a unique index on two columns. Those columns are also indexed. So my question is if I just can remove the indexes who were just for one column or if I have to use all three indexes:
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SQLAlchemy: cascade delete
...ession.query().filter().delete() (which doesn't put elements in the memory and deletes directly from db).
Using this method sqlalchemy's cascade='all, delete' doesn't work. There is a solution though: ON DELETE CASCADE through db (note: not all databases support it).
class Child(Base):
__table...
How to become an OpenCart guru? [closed]
... api calls on their official forums. I have experience with Zend framework and CodeIgniter framework. Can any OpenCart masters recommend me the best way to learn it and master in shortest amount of time? I have to do a big project with it soon.
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Android ListView headers
...ave ListView that has some kind of events on it. Events are sorted by day, and I would like to have header with date on it for every day, and then events listen below.
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How can I make a JPA OneToOne relation lazy
...eloping, we noticed that a view was particularly slow. I profiled the view and noticed that there was one query executed by hibernate which took 10 seconds even if there only were two object in the database to fetch. All OneToMany and ManyToMany relations were lazy so that wasn't the problem. Wh...
mongo group query how to keep fields
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@Juliomac, I believe if your desired output is $max/$min and keeping fields that are not in the $group _id, you can $sort before with the desired field then group and use $first or $last operators on any field. When accumulating, the idea to include other fields (which are accumula...