Exception: 

ORA-21525: attribute number or (collection element at index) string violated its constraints

Cause: Attribute value or collection element value violated its constraint.

Action: Change the value of the attribute or collection element such that it meets its constraints. The constraints are specified as part of the attribute or collection element’s schema information.

Error reason:

When passing data to stored procedures in C #, the user-defined object of Oracle is used. However, when passing in, some obj fields will throw this exception if the length of the value finally passed in is greater than that of the type definition. For example, this time type number (3) was passed in 1100

as like as two peas, it will probably have other problems, and it will also throw out this exception, which is not exactly the same as this encounter, but as a reference for solving problems.