Class ThinkingSphinx::Index::Builder
In: lib/thinking_sphinx/index/builder.rb
Parent: Object

The Builder class is the core for the index definition block processing. There are four methods you really need to pay attention to:

The first two of these methods allow you to define what data makes up your indexes. where provides a method to add manual SQL conditions, and set_property allows you to set some settings on a per-index basis. Check out each method‘s documentation for better ideas of usage.

Methods

Public Class methods

Public Instance methods

A method to allow adding fields from associations which have names that clash with method names in the Builder class (ie: properties, fields, attributes).

Example: indexes assoc(:properties).column

Use this method to add some manual SQL strings to the GROUP BY clause. You can pass in as many strings as you‘d like, they‘ll get joined together with commas later on.

  group_by "lat", "lng"

This is the method to add attributes to your index (hence why it is aliased as ‘attribute’). The syntax is the same as indexes, so use that as starting point, but keep in mind the following points.

An attribute can have an alias (the :as option), but it is always sortable - so you don‘t need to explicitly request that. You can specify the data type of the attribute (the :type option), but the code‘s pretty good at figuring that out itself from peering into the database.

Attributes are limited to the following types: integers, floats, datetimes (converted to timestamps), booleans, strings and MVAs (:multi). Don‘t forget that Sphinx converts string attributes to integers, which are useful for sorting, but that‘s about it.

Collection of integers are known as multi-value attributes (MVAs). Generally these would be through a has_many relationship, like in this example:

  has posts(:id), :as => :post_ids

This allows you to filter on any of the values tied to a specific record. Might be best to read through the Sphinx documentation to get a better idea of that though.

Adding SQL Fragment Attributes

You can also define an attribute using an SQL fragment, useful for when you would like to index a calculated value. Don‘t forget to set the type of the attribute though:

  has "age < 18", :as => :minor, :type => :boolean

If you‘re creating attributes for latitude and longitude, don‘t forget that Sphinx expects these values to be in radians.

This is how you add fields - the strings Sphinx looks at - to your index. Technically, to use this method, you need to pass in some columns and options - but there‘s some neat method_missing stuff happening, so lets stick to the expected syntax within a define_index block.

Expected options are :as, which points to a column alias in symbol form, and :sortable, which indicates whether you want to sort by this field.

Adding Single-Column Fields:

You can use symbols or methods - and can chain methods together to get access down the associations tree.

  indexes :id, :as => :my_id
  indexes :name, :sortable => true
  indexes first_name, last_name, :sortable => true
  indexes users.posts.content, :as => :post_content
  indexes users(:id), :as => :user_ids

Keep in mind that if any keywords for Ruby methods - such as id or name - clash with your column names, you need to use the symbol version (see the first, second and last examples above).

If you specify multiple columns (example 2), a field will be created for each. Don‘t use the :as option in this case. If you want to merge those columns together, continue reading.

Adding Multi-Column Fields:

  indexes [first_name, last_name], :as => :name
  indexes [location, parent.location], :as => :location

To combine multiple columns into a single field, you need to wrap them in an Array, as shown by the above examples. There‘s no limitations on whether they‘re symbols or methods or what level of associations they come from.

Adding SQL Fragment Fields

You can also define a field using an SQL fragment, useful for when you would like to index a calculated value.

  indexes "age < 18", :as => :minor

Handles the generation of new columns for the field and attribute definitions.

set_properties(*args)

Alias for set_property

This is what to use to set properties on the index. Chief amongst those is the delta property - to allow automatic updates to your indexes as new models are added and edited - but also you can define search-related properties which will be the defaults for all searches on the model.

  set_property :delta => true
  set_property :field_weights => {"name" => 100}
  set_property :order => "name ASC"
  set_property :select => 'name'

Also, the following two properties are particularly relevant for geo-location searching - latitude_attr and longitude_attr. If your attributes for these two values are named something other than lat/latitude or lon/long/longitude, you can dictate what they are when defining the index, so you don‘t need to specify them for every geo-related search.

  set_property :latitude_attr => "lt", :longitude_attr => "lg"

Please don‘t forget to add a boolean field named ‘delta’ to your model‘s database table if enabling the delta index for it. Valid options for the delta property are:

true false :default :delayed :datetime

You can also extend ThinkingSphinx::Deltas::DefaultDelta to implement your own handling for delta indexing.

Use this method to add some manual SQL conditions for your index request. You can pass in as many strings as you like, they‘ll get joined together with ANDs later on.

  where "user_id = 10"
  where "parent_type = 'Article'", "created_at < NOW()"

[Validate]