check for data transformation oracle etl

I am new to oracle and I would like to know how do we validate parent child relationship, compare range of values and validate data types as part of the ETL testing process. (The two tables could be T1 and T2). Please let me know a sample query.

example: T1 is the temporary loading table, And T2 is the new table. we need to make sure that all the data between T1 and T2 is valid with context of range of the value of the variables, the relationships, and data types.

Thanks, Santosh