I have two tables(Database: Microsoft SQL Server)
1) Parent
2) Child


There is one-to-one relationship between them

Parent table have primary field ANC_ID(int)
Child table have field ANC_ID(int)



Parent class have following relation with Child

@OneToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "ANC_ID")
private Child childString;

@Id
@Column(name = "ANC_ID")
private Integer annId;


Child declare relationship as follows

@OneToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "ANC_ID")
private Parent ParentString;

@Id
@Column(name = "CONFIG_ID")
private String configId;




List<Parent> parent= session.createCriteria(Parent.class).list();

On Retrieving data from the entity i got the following exception

org.hibernate.TypeMismatchException: Provided id of the wrong type. Expected: class java.lang.String, got class java.lang.Integer

But when i change table structure as
Parent table have primary field ANC_ID(varchar(50))
Child table have field ANC_ID(varchar(50))

i got following
ERROR [10:43:16] - Invalid column name 'CONFIG_ID'.
org.hibernate.exception.SQLGrammarException: could not load an entity: [com.myprog.hibernate.per.entity.Child#1]

But column name is not invalid


Where m going not as required
is there something to keep in mind while using hibernate that primary keys must be Integer type (not String) and auto increment must be there

or Child tables primary key must be int


What is the correct scenario in which one can implement as required