Refactor postgres adapter Database#execute internals
Support :each when preparing statements, useful for iterating over large datasets

Before, only :select and :all were supported, which load the entire
dataset in memory.  On adapters that can use Dataset#each without
loading the entire result set in memory, using :each for pure
iteration should result in better performance.

While here, I discovered a bug that Database#call did not pass the
block it was given.  This could cause unexpected behavior, since
the block would not be called but results would still be returned.
That's because for other prepared statement types, a block is
optional.  For each it is required, which is how I discovered the
bug.
Document some adapter-specific options in the main RDoc

In general, the methods that are overridden to add support for
these options are private, and Sequel doesn't publish RDoc for
private methods.  It also makes sense to document the options
on the methods where the options will be used.
Support partial indexes on Microsoft SQL Server

SQL Server 2008 enables support for partial indexes (which are
referred to as filtered indexes in Microsoft's documentation).
Update CHANGELOG
Fix possible threading issue in a spec

The previous code is wrong in that t1 is not guaranteed to have
exited.  t2 is required to still be alive, though.  So just
join the thread instead of checking that it is dead.
Fix integration test on JRuby 1.7

In JRuby 1.7, java.lang.Exception objects do not descend from
Exception, which broke this spec.  It seems very odd to me, but
this is going to be JRuby's documented behavior going forward,
so the spec should be adjusted.
In the optimistic locking plugin, make refresh and save after a failed save work correctly

Before, since instance filters were only cleared after a successful
save, if you rescued the error raised by save, refreshed and then
saved, it would add the lock column filter twice, once with the
old value and one with the new value.

The simplest way to fix this is just to make refreshing clear
the instance filters, since saving will add the correct one
back.

Note that this potentially could skip the instance filter if you
refreshed your model in a before_update after the instance filter
was added.  I doubt anyone would do that.
Fix incorrect spec description
Add pg_json extension, for working with PostgreSQL 9.2's new json type

This is modeled on the pg_hstore and pg_array extensions, using
the same DelegateClass approach.

It does not currently support plain numbers or strings in a json
column, which PostgreSQL supports.  Support for that could
be added later if there is demand, just be adding custom parsers
and more DelegateClasses.  However, I think PostgreSQL is wrong
in the this case and it shouldn't be accepting those values,
which is why the extension doesn't currently support it.  Another
reason is that typecasting from a string would then be ambiguous,
since you wouldn't know whether it was literal JSON that should
be parsed, or represented a plain string that should be wrapped
in a DelegateClass.
Give better error message for bad JDBC URL usage

At least on PostgreSQL, if you use a bad JDBC URL string,
driver.new.connect can return nil in this case.  You would
get an error later inside setup_connection, but it's better
to raise the error earlier.
Remove Database#execute_insert override from pg_auto_parameterize

Since 3.35.0, this method is no longer called, since all inserts
use RETURNING now.
Always attempt to load the ActiveSupport inflector in the plugin specs

This attempts to load the ActiveSupport inflector first, before
the Sequel inflector, since the Sequel inflector should then
override the ActiveSupport inflector.  Remove the check for the
ActiveSupport inflector in the inflector spec, since it should
never take affect.

You'll know if the ActiveSupport inflector is still in place if
the inflector specs start failing.
Add specs for prepared statements plugin using placeholder type specifiers
Add link to pg_json extension to plugins page
Recognize another mysql2 disconnect error message
Add a spec for rcte_tree when dataset requires column aliases for recursive CTEs
Add a spec for calling a serializer with an unregistered format symbol
Add spec for tactical eager loading with undefined association

While here, fix the RDoc for tactical eager loading.  The original
implementation used the identity_map, but I'm pretty sure I made
it not require the identity_map before adding it to Sequel.
Only check coverage for extensions and plugins in spec_plugin_cov

This removes the other files from the output, since they are just
noise.