Option handling and query assembly used by the functions BoxTurtle.Schema.Query generates.
Public so custom query extensions can reuse them; add_filters/2 in particular is handy for adding
filters to the options an extension receives.
Summary
Functions
Merges filters into the :filters already present in opts.
True when the options request an aggregate (e.g. a count).
The columns to count distinctly in an aggregate (sort directions dropped).
Builds an aggregate query. Only :count is supported.
Runs an aggregate query: a single integer without grouping, otherwise a list of maps holding the grouped
columns and :count.
The :aggregate option, or nil.
Applies sorting and pagination.
Applies grouping and filters.
Returns the :distinct columns unchanged if repo's adapter supports DISTINCT ON, and raises
ArgumentError if it is known not to (SQLite3, MyXQL, Tds). The adapter would otherwise only fail
once the query runs.
Fetches a call-time option, falling back to module_default, or to no_default_value when the
ignore_defaults: true option is set.
Adds group_by clauses. String column names must already exist as atoms.
The :group_by columns.
True when the ignore_defaults: true option is set.
The associations to preload.
The :page option (see BoxTurtle.Schema.Pagination).
Preloads associations through LEFT JOINs, so rows and their associations come back from the
database in a single query instead of one extra query per association.
The :distinct columns for list queries.
The sort specification.
Adds a distinct clause.
Restricts the query to one key: a single value for primary_key, or a map/keyword list of
column values for composite keys.
Functions
Merges filters into the :filters already present in opts.
True when the options request an aggregate (e.g. a count).
The columns to count distinctly in an aggregate (sort directions dropped).
@spec aggregate_query!(Ecto.Queryable.t(), :count, module(), keyword()) :: Ecto.Query.t()
Builds an aggregate query. Only :count is supported.
@spec aggregate_result!(Ecto.Queryable.t(), :count, [atom()], module(), keyword()) :: integer() | [map()]
Runs an aggregate query: a single integer without grouping, otherwise a list of maps holding the grouped
columns and :count.
The :aggregate option, or nil.
@spec build_listings!(Ecto.Queryable.t(), module(), list(), keyword(), pos_integer()) :: Ecto.Queryable.t()
Applies sorting and pagination.
@spec build_query!(Ecto.Queryable.t(), module(), keyword()) :: Ecto.Queryable.t()
Applies grouping and filters.
Returns the :distinct columns unchanged if repo's adapter supports DISTINCT ON, and raises
ArgumentError if it is known not to (SQLite3, MyXQL, Tds). The adapter would otherwise only fail
once the query runs.
Counts are not affected: count(distinct: ...) uses COUNT(DISTINCT column), which every adapter supports.
Fetches a call-time option, falling back to module_default, or to no_default_value when the
ignore_defaults: true option is set.
@spec group(Ecto.Queryable.t(), nil | atom() | String.t() | [atom() | String.t()]) :: Ecto.Queryable.t()
Adds group_by clauses. String column names must already exist as atoms.
The :group_by columns.
True when the ignore_defaults: true option is set.
The associations to preload.
@spec paging(keyword()) :: BoxTurtle.Schema.Pagination.page_spec()
The :page option (see BoxTurtle.Schema.Pagination).
@spec preloads(Ecto.Queryable.t(), nil | atom() | list(), atom()) :: Ecto.Queryable.t()
Preloads associations through LEFT JOINs, so rows and their associations come back from the
database in a single query instead of one extra query per association.
assocs takes the usual preload shapes, nested to any depth: :author, [:author, :tags],
[author: [:company], comments: :user]. Duplicates are merged.
Joining a to-many association repeats each parent row once per child, so LIMIT, OFFSET and
DISTINCT would count child rows. When the query has any of them, they are applied in a subquery
selecting primary_key, and the joins are made against that selection.
The :distinct columns for list queries.
The sort specification.
@spec unique(Ecto.Queryable.t(), nil | atom() | list()) :: Ecto.Queryable.t()
Adds a distinct clause.
@spec where_key(Ecto.Queryable.t(), term(), atom()) :: Ecto.Query.t()
Restricts the query to one key: a single value for primary_key, or a map/keyword list of
column values for composite keys.