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Migrating to RethinkDB 1.12

There are a number of breaking changes in RethinkDB 1.12 you should be aware of before migrating.

Data migration

First, make sure to go through the regular data migration process, since the 1.12 file format isn't compatible with file formats generated by previous versions of RethinkDB.

Then, replace group_by and grouped_map_reduce commands in your applications with the new group command.

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r.http("https://hacker-news.firebaseio.com/v0/topstories.json").limit(5).map(
  r.http(r.add("https://hacker-news.firebaseio.com/v0/item/",
               r.row.coerceTo('string'),
               ".json"))
);

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Keybase proof

I hereby claim:

• I am coffeemug on github.
• I am coffeemug (https://keybase.io/coffeemug) on keybase.
• I have a public key whose fingerprint is 5925 55F9 CC4C 2D4E E82E 97AA A33E 7D8E 5279 41E9

To claim this, I am signing this object:

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/* This program demonstrates a bug in the Linux kernel version 3.2.0 using the
`ext4` filesystem.
 
Steps to compile:
 
    $ gcc -o demo demo.c -laio
 
Steps to reproduce:
 
1. Run `./demo FILE`, where `FILE` is the path where the program will put the

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test

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r.table(Build.__tablename__).get(build_id).update({'result': r.table(Build.__tablename__).get(build_id)['result'].append(line)}).run()

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r.table(Build.__tablename__).get(build_id).update({'result': r['result'].append(line)}).run()

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--------------------------------------------------------------------------------
  n        time(i)         total(B)   useful-heap(B) extra-heap(B)    stacks(B)
--------------------------------------------------------------------------------
 78 57,030,430,673    1,440,292,888    1,227,094,500   213,198,388            0
85.20% (1,227,094,500B) (heap allocation functions) malloc/new/new[], --alloc-fns, etc.
->26.62% (383,410,176B) 0x207EA0D: malloc_aligned(unsigned long, unsigned long) (utils.cc:234)
| ->13.94% (200,802,304B) 0x186277E: artificial_stack_t::artificial_stack_t(void (*)(), unsigned long) (context_switching.cc:37)
| | ->13.94% (200,802,304B) 0x1862F4D: coro_t::coro_t() (coroutines.cc:127)
| |   ->13.94% (200,802,304B) 0x1863DAA: coro_t::get_coro() (coroutines.cc:356)
| |     ->06.41% (92,274,688B) 0x18BD37A: coro_t* coro_t::get_and_init_coro<boost::_bi::bind_t<void, boost::_mfi::mf2<void, mc_inner_buf_t, bool, file_account_t*>, boost::_bi::list3<boost::_bi::value<mc_inner_buf_t*>, boost::_bi::valu

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The getField command now works on sequences

In the previous versions of RethinkDB you could get a subset of an object using the pluck command, and the value of a specific field using the getField command (accessible via () in Javascript and [] in Python and Ruby):

r.expr({a: 1, b: 1}).pluck('a')
// returns {a: 1}

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Syntax for plucking nested objects

In the previous versions of RethinkDB you could use the pluck command to extract only specific attributes from an object or a sequence of objects:

r.expr({a: 1, b: {c: 1, d: 1}}).pluck('b')
// returns `b: {c: 1, d: 1}`