There are a few different ways of getting the number of bands, each with their own tradeoffs.
Usually the way to get Airtable to put the total number of records in a table cell is to have all the records linked to a record in the second table. Then Airtable can use a count field or a rollup field to sum the number of linked records. However, if you do not already have all the records linked to a single record in another table, it might require some base redesign. You would need an onging method of making sure that all new records are linked correctly, which can be automated with with Zapier.
If you are using the Standard REST API to put information on your website, you can have the code that uses the API calculate the number of bands for you. Although there Standard REST API cannot directly tell you the number of records, you can do successive reads of records (returning zero fields to reduce the network traffic) and see how many records are returned. This would require significant coding and might be difficult to maintain.
If you do not need the number to update in real-time, and can have a human push a “run” button whenever you want to update the totals (e.g. every morning), you can have a script in Scripting block calculate the number of records and put that information in a table. This method has a lot of flexibility, and is easier to implement than going through the Standard REST API. Unfortunately, you have to remember to press the “run” button.
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