Data Lake Analytics (DLA) implicitly converts numeric and character values into the correct type. DLA does not automatically convert between character and numeric types. For example, DLA cannot automatically convert data of the Long type returned from a query into data of the VARCHAR type.
Conversion functions
cast(value AS type) → type
This function explicitly converts a value into a type. It can be used to convert a character value into a numeric type, or a numeric value into a character type.
Miscellaneous
typeof(expr) → varchar
Types of return results of expressions:
SELECT typeof(123); -- integer
SELECT typeof('cat'); -- varchar(3)
SELECT typeof(cos(2) + 1.5); -- double