node.js - Mongoose query model where field type is an array

Question

I had to change the schema type of a field (location) in my Course model from array to string, I however need to change all previous data I have from type array to string and then do some data manipulation to get what I need. New data are being stored as String. How do I query all courses having location field type as array and where zip code exists so that I can do proper data manipulation?

const coursesWithArrayLocation = await Course.find({zipcode: { $exists: true }});

question from:https://stackoverflow.com/questions/65858827/mongoose-query-model-where-field-type-is-an-array

Answer 1

Try $type operator to match specific type of field,

• match type by 2 ways first is Number and second is Alias, where array type Number is 4 and Alias is "array"

const coursesWithArrayLocation = await Course.find({
  location: { $type: "array" },
  zipcode: { $exists: true }
})

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