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i would like to create a many to many relationship between two tables "Term" and "Synonym" but i dont now how to write them Models !! Any Help ! and thnx a lot.

Samer Sboui
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  • Welcome to stackoverflow. Please include a clear problem description and if possible some minimal code. For guidance please check the [how to ask](https://stackoverflow.com/help/how-to-ask) page and [how to create a minimal example](https://stackoverflow.com/help/mcve). – 5th Jul 29 '18 at 20:33
  • ok i will thnx ! – Samer Sboui Jul 29 '18 at 20:44

1 Answers1

0

For that you will need 2 models. In Term class:

@Entity
public class Term extends Models {
    @Id
    private String id;

    @ManyToMany
    private List<Synonym> synonyms = new ArrayList<>();
}

In Synonym class:

@Entity
public class Synonym extends Models {
    @Id
    private String id;

    @ManyToMany
    @JoinTable
    private List<Term> terms = new ArrayList<>();
}

And for your database structure it will look like this:

CREATE TABLE term {
    id CHAR(255)
}

CREATE TABLE synonym {
    id CHAR(255)
}

CREATE TABLE term_synonym {
    term_id CHAR(255),
    synonym_id CHAR(255),
    PRIMARY KEY(term_id, synonym) // This is needed to avoid having the same many to many relation
}

term_synonym table is needed to maintain the relationship of @ManyToMany in database level.

hong823
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