Specifies the type of the returned data.
Enumeration values
RT_NONE: specifies that no value is returned. This is the default value.
RT_PK: specifies that only the primary key column is returned.
RT_AFTER_MODIFY: specifies that the changed value of the column is returned. This parameter can be used to return the value of the column on which the atomic counter operation is performed to implement the atomic counter feature.
enum ReturnType {
RT_NONE = 0;
RT_PK = 1;
RT_AFTER_MODIFY = 2;
}