Array type assignments

For array types, the validity of an assignment to an SQL array variable or parameter is determined according to the following rules:

If the right hand side of the assignment is an SQL array variable or parameter, the TRIM_ARRAY function, or a CAST expression, then its type must be the same type as the SQL array variable or parameter on the left hand side of the assignment.
If the right hand side of the assignment is an array constructor or the ARRAY_AGG function, then it is implicitly cast to the type of the SQL array variable or parameter on the left hand side.