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copied!<p><strong>Edit:</strong> <em>Okay, so this doesn't actually solve the question asked, because eidylon is tied to an existing ContentProvider as mentioned in their question. However, this does cover how you do a JOIN if you own the ContentProvider source and API. So I'll leave it for those who want to know how to handle that case.</em></p> <hr> <p>This is easy! But unintuitive... :)</p> <pre><code>query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) </code></pre> <p>Okay, so what is URI? Typically, you have one URI per table.</p> <p><code>content://com.example.coolapp.contacts</code> serves data out of your <code>CONTACTS</code> table. <code>content://com.example.coolapp.groupmembers</code> serves data out of your <code>GROUPMEMBERSHIP</code> table.</p> <p>But URI is really just a string. Use it however you like. Make a block of code in your ContentProvider that responds to <code>content://com.example.coolapp.contacts_in_group</code>. Within that block of code in the ContentProvider, you can get raw access to your SQLite DB, unfettered by the limited <code>query()</code> data model. Feel free to use it!</p> <p>Define your selection fields however you like. They don't <em>have</em> to map to table column names -- map them how you need to, in order to get your parameters in.</p> <p>Define your projection how you need -- It may contain columns from both tables after the join.</p> <p>Bing, you're done. Google does this same model internally in their own code -- Go look at the Contacts provider API -- you see "bla.RawContact" and "bla.Contact" and etc as content URIs. Each serves data out of the same table in the DB -- the different URIs just provide different <em>views</em> of that same table!</p>

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