A single column doesn’t make sense to me. I’m not sure why the rows would be in the database if they don’t have a price.
In any event, an index on one VARCHAR column is going to have an infinitely large cardinality (estimated number of unique values) compared to a numeric column for the price and a boolean column for “unsuitable_for_children” which would have a cardinality of 2.
well, I considered the value to be an admission conditional which means the condition on which entrance is permitted is whatever that value may be. ‘unsuitable’ means no entry and 25.00 means you can come in. whilst one is numeric tha other is text but they sort of fell into the same category when I was thinking like that.