Selecto.Pivot (Selecto v0.3.8)
Pivot functionality for retargeting joined tables as primary query focus.
The Pivot feature allows you to shift the perspective of a Selecto query from the source table to any joined table, while preserving existing filters through subqueries.
examples
Examples
# Basic pivot - shift from events to orders
selecto
|> Selecto.filter([{"event_id", 123}])
|> Selecto.pivot(:orders)
|> Selecto.select(["product_name", "quantity"])
# This generates SQL like:
# SELECT o.product_name, o.quantity
# FROM orders o
# WHERE o.attendee_id IN (
# SELECT a.attendee_id FROM events e
# JOIN attendees a ON e.event_id = a.event_id
# WHERE e.event_id = 123
# )
configuration-options
Configuration Options
:preserve_filters- Whether to preserve existing filters in subquery (default: true):subquery_strategy- How to generate the subquery (:in,:exists,:join)
Link to this section Summary
Functions
Calculate the join path from the source table to the target table.
Get the pivot configuration from a Selecto query.
Check if a Selecto query has pivot configuration applied.
Pivot the query to focus on a different table while preserving existing context.
Reset/remove pivot configuration from a Selecto query.
Validate that a pivot path exists and is traversable.
Link to this section Functions
calculate_join_path(selecto, target_schema)
@spec calculate_join_path(Selecto.Types.t(), atom()) :: {:ok, [atom()]} | {:error, String.t()}
Calculate the join path from the source table to the target table.
This function analyzes the domain configuration to find the shortest path of associations from the current source to the target schema.
get_pivot_config(selecto)
@spec get_pivot_config(Selecto.Types.t()) :: Selecto.Types.pivot_config() | nil
Get the pivot configuration from a Selecto query.
has_pivot?(selecto)
@spec has_pivot?(Selecto.Types.t()) :: boolean()
Check if a Selecto query has pivot configuration applied.
pivot(selecto, target_schema, opts \\ [])
@spec pivot(Selecto.Types.t(), atom(), keyword()) :: Selecto.Types.t()
Pivot the query to focus on a different table while preserving existing context.
parameters
Parameters
selecto- The Selecto struct to pivottarget_schema- Atom representing the target table to pivot toopts- Optional configuration (see module docs)
returns
Returns
Updated Selecto struct with pivot configuration applied.
examples
Examples
selecto
|> Selecto.filter([{"event_id", 123}])
|> Selecto.pivot(:orders)
|> Selecto.select(["product_name"])reset_pivot(selecto)
@spec reset_pivot(Selecto.Types.t()) :: Selecto.Types.t()
Reset/remove pivot configuration from a Selecto query.
validate_pivot_path(selecto, join_path)
@spec validate_pivot_path(Selecto.Types.t(), [atom()]) :: :ok | {:error, String.t()}
Validate that a pivot path exists and is traversable.