Question

我在使用以下结构时遇到性能问题，目前我必须上课

1.Product 2.Category

1个产品有很多类别
2类有很多产品
1个类别有很多类别（自我）

产品类---＆gt;

<div class="form-file-upload">

  <button type="button" class="close"></button>

</div>

}

类别类----＆gt;

@Entity
@Table(name = ProductService.TABLE_NAME)
public class ProductService {

    public static final String TABLE_NAME = "BB_Product_Service";
    public static final String TABLE_NAME_PROD_SUB_CAT = "BB_Product_Sub_category";
    public static final String COLUMN_PRODUCT_ID = "pk_product_id";
    public static final String COLUMN_PRODUCT_NAME = "product_name";
    public static final String COLUMN_PRODUCT_DESCRIPTION = "product_description";
    public static final String COLUMN_PRODUCT_NOTE = "product_note";
    public static final String COLUMN_PRODUCT_PRICE = "product_price";
    public static final String COLUMN_PRODUCT_MAINTENANCE = "product_maintenance";
    public static final String COLUMN_PRODUCT_EXPENSES = "product_expenses";
    public static final String COLUMN_STATUS = "status";
    public static final String USER_ADDED_BY_FOREIGN_KEY = "fk_added_by";
    public static final String COLUMN_USER_ADDED_ON = "added_on";
    public static final String USER_MODIFIED_BY_FOREIGN_KEY = "fk_modified_by";
    public static final String COLUMN_USER_MODIFIED_ON = "modified_on";

    public static final String TABLE_PRODUCT_CATEGORY = "BB_Product_category";


    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = COLUMN_PRODUCT_ID)
    private int productId;

    @Column(name = COLUMN_PRODUCT_NAME, columnDefinition = "VARCHAR(255)", nullable = false)
    private String productName;

    @Column(name = COLUMN_PRODUCT_DESCRIPTION, columnDefinition = "VARCHAR(500)", nullable = true)
    private String productDescription;

    @Column(name = COLUMN_PRODUCT_NOTE, columnDefinition = "VARCHAR(255)", nullable = true)
    private String productNote;

    @Column(name = COLUMN_PRODUCT_PRICE, columnDefinition = "INT(10)", nullable = true)
    private int productPrice;

    @Column(name = COLUMN_PRODUCT_MAINTENANCE, columnDefinition = "INT(10)", nullable = true)
    private int productMaintenance;

    @Column(name = COLUMN_STATUS, columnDefinition = "TINYINT(1) DEFAULT 1", nullable = false)
    private int status;

    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = COLUMN_USER_ADDED_ON, columnDefinition = "DATETIME", nullable = false)
    private Date userAddedOn;

    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = COLUMN_USER_MODIFIED_ON, columnDefinition = "DATETIME", nullable = true)
    private Date userModifiedOn;


    @ManyToMany(cascade = CascadeType.ALL)
    @JoinTable(name = TABLE_PRODUCT_CATEGORY, joinColumns = @JoinColumn(name = COLUMN_PRODUCT_ID), inverseJoinColumns = @JoinColumn(name = Category.COLUMN_CATEGORY_ID))
    @Where(clause="status=1")
    private List<Category> categories;

       //Setter an Getter

从上面的结构一切都运行良好但仍然遇到性能问题，如何才能提高性能我可以将manyTomany注释放在类别实体中吗？请帮帮我.....提前谢谢

面对ManyToMany关系中的性能问题

0 个答案: