Packages
ecto
3.5.0-rc.1
3.14.1
3.14.0
3.13.6
3.13.5
3.13.4
3.13.3
3.13.2
3.13.1
3.13.0
3.12.6
3.12.5
3.12.4
3.12.3
3.12.2
3.12.1
3.12.0
3.11.2
3.11.1
3.11.0
3.10.3
3.10.2
3.10.1
3.10.0
3.9.6
3.9.5
3.9.4
3.9.3
3.9.2
3.9.1
3.9.0
3.8.4
3.8.3
3.8.2
3.8.1
3.8.0
3.7.2
3.7.1
3.7.0
3.6.2
3.6.1
3.6.0
3.5.8
3.5.7
3.5.6
3.5.5
3.5.4
3.5.3
3.5.2
3.5.1
3.5.0
3.5.0-rc.1
3.5.0-rc.0
3.4.6
3.4.5
3.4.4
3.4.3
3.4.2
3.4.1
3.4.0
3.3.4
3.3.3
3.3.2
3.3.1
3.3.0
3.2.5
3.2.4
3.2.3
3.2.2
3.2.1
3.2.0
3.1.7
3.1.6
3.1.5
3.1.4
3.1.3
3.1.2
3.1.1
3.1.0
3.0.9
3.0.8
3.0.7
3.0.6
3.0.5
3.0.4
3.0.3
3.0.2
3.0.1
3.0.0
3.0.0-rc.1
3.0.0-rc.0
2.2.12
2.2.11
2.2.10
2.2.9
2.2.8
2.2.7
2.2.6
2.2.5
2.2.4
2.2.3
2.2.2
2.2.1
2.2.0
2.2.0-rc.1
2.2.0-rc.0
2.1.6
2.1.5
2.1.4
2.1.3
2.1.2
2.1.1
2.1.0
2.1.0-rc.5
2.1.0-rc.4
2.1.0-rc.3
2.1.0-rc.2
2.1.0-rc.1
2.1.0-rc.0
2.0.6
2.0.5
2.0.4
2.0.3
2.0.2
2.0.1
2.0.0
2.0.0-rc.6
2.0.0-rc.5
2.0.0-rc.4
2.0.0-rc.3
2.0.0-rc.2
2.0.0-rc.1
2.0.0-rc.0
2.0.0-beta.2
2.0.0-beta.1
2.0.0-beta.0
1.1.9
1.1.8
1.1.7
1.1.6
1.1.5
1.1.4
1.1.3
1.1.2
1.1.1
1.1.0
1.0.7
1.0.6
1.0.5
1.0.4
1.0.3
1.0.2
1.0.1
1.0.0
0.16.0
0.15.0
0.14.3
0.14.2
0.14.1
0.14.0
0.13.1
0.13.0
0.12.1
0.12.0
0.12.0-rc
0.11.3
0.11.2
0.11.1
0.11.0
0.10.3
0.10.2
0.10.1
0.10.0
0.9.0
0.8.1
0.8.0
0.7.2
0.7.1
0.7.0
0.6.0
0.5.1
0.5.0
0.4.0
0.3.0
0.2.8
0.2.7
0.2.6
0.2.5
0.2.4
0.2.3
0.2.2
0.2.1
0.2.0
0.1.0
A toolkit for data mapping and language integrated query for Elixir
Current section
Files
Jump to
Current section
Files
lib/ecto/adapter/queryable.ex
defmodule Ecto.Adapter.Queryable do
@moduledoc """
Specifies the query API required from adapters.
If your adapter is only able to respond to one or a couple of the query functions,
add custom implementations of those functions directly to the Repo
by using `c:Ecto.Adapter.__before_compile__/1` instead.
"""
@typedoc "Proxy type to the adapter meta"
@type adapter_meta :: Ecto.Adapter.adapter_meta()
@typedoc "Ecto.Query metadata fields (stored in cache)"
@type query_meta :: %{sources: tuple, preloads: term, select: map}
@typedoc """
Cache query metadata that is passed to `c:execute/5`.
The cache can be in 3 states, documented below.
If `{:nocache, prepared}` is given, it means the query was
not and cannot be cached. The `prepared` value is the value
returned by `c:prepare/2`.
If `{:cache, cache_function, prepared}` is given, it means
the query can be cached and it must be cached by calling
the `cache_function` function with the cache entry of your
choice. Once `cache_function` is called, the next time the
same query is given to `c:execute/5`, it will receive the
`:cached` tuple.
If `{:cached, update_function, reset_function, cached}` is
given, it means the query has been cached. You may call
`update_function/1` if you want to update the cached result.
Or you may call `reset_function/1`, with a new prepared query,
to force the query to be cached again. If `reset_function/1`
is called, the next time the same query is given to
`c:execute/5`, it will receive the `:cache` tuple.
"""
@type query_cache :: {:nocache, prepared}
| {:cache, cache_function :: (cached -> :ok), prepared}
| {:cached, update_function :: (cached -> :ok), reset_function :: (prepared -> :ok), cached}
@type prepared :: term
@type cached :: term
@type options :: Keyword.t()
@type selected :: term
@doc """
Commands invoked to prepare a query.
It is used on `c:Ecto.Repo.all/2`, `c:Ecto.Repo.update_all/3`,
and `c:Ecto.Repo.delete_all/2`. If returns a tuple, saying if
this query can be cached or not, and the `prepared` query.
The `prepared` query is any term that will be passed to the
adapter's `c:execute/5`.
"""
@callback prepare(atom :: :all | :update_all | :delete_all, query :: Ecto.Query.t()) ::
{:cache, prepared} | {:nocache, prepared}
@doc """
Executes a previously prepared query.
The `query_meta` field is a map containing some of the fields
found in the `Ecto.Query` struct, after they have been normalized.
For example, the values `selected` by the query, which then have
to be returned, can be found in `query_meta`.
The `query_cache` and its state is documented in `t:query_cache/0`.
The `params` is the list of query parameters. For example, for
a query such as `from Post, where: [id: ^123]`, `params` will be
`[123]`.
Finally, `options` is a keyword list of options given to the
`Repo` operation that triggered the adapter call. Any option is
allowed, as this is a mechanism to allow users of Ecto to customize
how the adapter behaves per operation.
It must return a tuple containing the number of entries and
the result set as a list of lists. The entries in the actual
list will depend on what has been selected by the query. The
result set may also be `nil`, if no value is being selected.
"""
@callback execute(adapter_meta, query_meta, query_cache, params :: list(), options) ::
{integer, [[selected]] | nil}
@doc """
Streams a previously prepared query.
See `c:execute/5` for a description of arguments.
It returns a stream of values.
"""
@callback stream(adapter_meta, query_meta, query_cache, params :: list(), options) ::
Enumerable.t
@doc """
Plans and prepares a query for the given repo, leveraging its query cache.
This operation uses the query cache if one is available.
"""
def prepare_query(operation, repo_name_or_pid, queryable) do
{adapter, %{cache: cache}} = Ecto.Repo.Registry.lookup(repo_name_or_pid)
{_meta, prepared, params} =
queryable
|> Ecto.Queryable.to_query()
|> Ecto.Query.Planner.ensure_select(operation == :all)
|> Ecto.Query.Planner.query(operation, cache, adapter, 0)
{prepared, params}
end
@doc """
Plans a query using the given adapter.
This does not expect the repository and therefore does not leverage the cache.
"""
def plan_query(operation, adapter, queryable) do
query = Ecto.Queryable.to_query(queryable)
{query, params, _key} = Ecto.Query.Planner.plan(query, operation, adapter)
{query, _} = Ecto.Query.Planner.normalize(query, operation, adapter, 0)
{query, params}
end
end