Question about has_online_content_ssim indexing rule

[elohanlon]

Hello,

Just writing in with a question. While working on our Arclight app, we noticed that Arclight currently uses an "_ssim" field for something that appears to index a single boolean value (wrapped in an array):

https://github.com/projectblacklight/arclight/blob/a49ae6af6739f79844f067067552b9fd32198ad3/lib/arclight/traject/ead2_component_config.rb#L210

Is _ssim is preferred by the Arclight maintainers in cases like this, rather than something like a _bsi ("boolean stored int") field? Although there isn't currently a _bsi field defined in the example solr schema.xml file (https://github.com/projectblacklight/arclight/blob/a8dc92f7b0c852bdef7f5ab838c97aec6c75c1bc/solr/conf/schema.xml), one could be added.

We have a similar indexing case for another field, so I thought it would be good to ask this here, in case there are any advantages to _ssim that I hadn't thought of.

Thanks!