Use SQL COUNT and LIMIT 1 queries for none? and one? methods if no block or limit is given,
instead of loading the entire collection to memory. The any? and many? methods already
follow this behavior.
[Eugene Gilburg & Rafael Mendonça França]
"active_support/testing/stream" is already required in `test_case.rb`.
Furthermore the test "test/cases/migration_test.rb" could no longer be executed
directly.
In addition to cleaning up the implementation, this allows type casting
behavior to be applied consistently everywhere. (#where for example). A
good example of this was the previous need for handling value to key
conversion in the setter, because the number had to be passed to `where`
directly. This is no longer required, since we can just pass the string
along to where. (It's left around for backwards compat)
Fixes#18387
It looks like the only reason `current_scope` was thread local on
`base_class` instead of `self` is to ensure that when we call a named
scope created with a proc on the parent class, it correctly uses the
default scope of the subclass. The reason this wasn't happening was
because the proc captured `self` as the parent class, and we're not
actually defining a real method. Using `instance_exec` fixes the
problem.
Fixes#18806
As far as I can tell, the original reason that this behavior was added
has been sufficiently resolved elsewhere, as we no longer remove the
encoding of strings coming out of the database.
The latest version of the PG gem can actually convert the primitives for
us in C code, which gives a pretty substantial speed up. A few cases
were only there to add the `infinity` method, which I just put on the
range type (which is the only place it was used). Floats also needed to
parse `Infinity` and `NaN`, but it felt reasonable enough to put that on
the generic form.
MySQL rejects to remove an index which is used in a foreign key constraint:
```
ActiveRecord::StatementInvalid: Mysql2::Error: Cannot drop index 'index_copies_on_title_id': needed in a foreign key constraint: ALTER TABLE `copies` DROP `title_id`
```
Removing the constraint before removing the column (and the index) solves this problem.
`quote_default_expression` and `quote_default_value` are almost the same
handling for do not quote default function of `:uuid` columns. Rename
`quote_default_value` to `quote_default_expression`, and remove
duplicate code.
The various databases don't actually need significantly different
handling for this behavior, and they can achieve it without knowing
about the type of the object.
The old implementation was returning a string, which will cause problems
such as breaking TZ aware attributes, and making it impossible for the
adapters to supply their logic for time objects.
