Some questions

[kindlychung]

Hi Harri, thanks for your nice work.

Some questions about the docs:

• fast: 'single' or 'multi' - Set the field as a fast field with a given cardinality which makes it either a single-value or multi-value field. Fast fields are designed for random access. Access time are similar to a random lookup in an array. If more than one value is associated to a fast field, only the last one is kept.

Could you explain the difference between single-value and multi-value field?

What is a facet field? What are search fields and boost fields? If a field has indexed set to true, will it be automatically a search field?

Looking forward to your answers and I can help you update the docs if desired.

[ChillFish8]

Hi! Sorry for the appalling response time! Never got a notification about this.

These have been changed in the latest 0.9 release because it's a tad confusing. But put simply. It just determines how lnx stores integers. A FAST field can be used for sorting or query access and has a lower overhead when accessing.

What is a facet field?

A hierarchical facet field is a field that allows you to organise and group documents together with a given hierarchy.
i.e if I have a bunch of documents for my e-commerce site, I may have some docs with facets as so:

electronics/kitchen/toaster

This means that the document belongs to the toaster sub-group which intern, belongs to the kitchen sub-group, and which intern belongs to the electronics group/parent.
At query time this allows you to effectively go "Show me all electronics" but then also be able to filter down to things like "All kitchen electronics" without needing multiple fields or text fields which are slower to access.

If a field has an indexed set to true, will it be automatically a search field?

No, they can be searched, but search_fields are explicitly the default search fields used for things like the fuzzy query or normal query.
However, if no search fields are passed, it will indeed default to all indexed text fields.

What are search fields and boost fields?

• Search fields are the default set of fields to be used when searching with the fuzzy, normal and more-like-this queries.
• Boost fields allow you to adjust how much weight you want each match on a given field to carry. I.e you probably want matches in a title to have more weight over the description.