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amazon-dynamodbdynamodb-queries

DynamoDB: Query items where a field has specific type

I have a legacy table in DynamoDB, and this table contains a non-key field term which is usually a Number, but in some cases it is a String containing a number

I want to query all items having this field a String value, and it seems to be a pretty complex task

I tried NOT Contains (term, {S: "a"}) and it returns all items with Numbers and Strings

The only solution which works is to use

begins_with(term, {S: "0"} OR
begins_with(term, {S: "1"} OR
...
begins_with(term, {S: "9"}

I suppose that this is not the best solution

Maybe someone knows cleaner solution?

Solution

  • You should use the filter function attribute_type:

    attribute_type(term, "S"}

    https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Expressions.OperatorsAndFunctions.html#Expressions.OperatorsAndFunctions.Functions