... Yeah, yeah, I know traditional joins don't exist. I actually like the freebase query methodology in theory, just having a little trouble getting it to actually work for me : )
Anyone have a dumb-simple example of getting Freebase data via MQL that pulls from two different "tables"? In particular, I'm trying to get automotive data... so for example, pulling fields from both /automotive/model_year and /automotive/trim_level.
I've read the documentation (for hours开发者_开发百科 actually). There's a distinct possibility that I'm looking right at such an example somewhere and just not seeing it because my OLTP brain just doesn't comprehend what it's seeing.
* Note * ... that the two "types" I'm working with above are siblings, not parent/child. Does freebase even allow joining data between sibling nodes... I see examples of queries pulling from parent/child, but not from siblings I don't think (or I've overlooked them).
Basically, could you not just restrict the queries according to the user's input?
When the user selects the year, you get all makes that have a matching model year:
[{
"model_s": [{
"model_years": [{
"year": [{
"type": "/type/datetime",
"value<": "2010", // User input
"value>=": "2009" // User input
}],
"type": "/automotive/model_year"
}],
"type": "/automotive/model"
}],
"id": null,
"name": null,
"type": "/automotive/make"
}]
If the make is selected and you need the models for that make and year:
[{
"model_years": [{
"year": [{
"type": "/type/datetime",
"value<": "2010", // User input from above
"value>=": "2009" // User input from above
}],
"type": "/automotive/model_year"
}],
"id": null,
"name": null,
"type": "/automotive/model",
"make": [{
"id": "/en/volkswagen", // User input
"type": "/automotive/make"
}]
}]
Or did I just not understand your problem correctly?
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