string function
Applies to: 
Databricks SQL Databricks Runtime
Casts the value expr to STRING. This function is a synonym for cast(expr AS STRING). See cast function for details.
Syntax
string(expr)
Arguments
expr: An expression that can be cast toSTRING.
Returns
A STRING.
If expr is not a STRING, the result STRING is assigned the default collation.
Otherwise, the result collation matches the collation of expr.
Examples
SQL
> SELECT string(5);
5
> SELECT string(current_date);
2021-04-01