Question

我正在使用@Multitenant（SINGLE_TABLE）来支持多租户。为解决n + 1问题，我使用了eclipselink的批量获取功能。

df = pd.DataFrame(data={'ev_type': np.random.choice(list("ABCDWK"), size=100,replace=True), 'ev_time': pd.date_range(start=pd.datetime(2016,1,1),freq='M', periods=100)})

当我使用：

查询时

@Entity
public class TestEntity implements Serializable {
    @Id
    @Column
    private Long id;

    @OneToMany(mappedBy = "testEntity", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    @BatchFetch(BatchFetchType.IN)
    private List<TestEntityLine> lines = new ArrayList<>();
}

@Entity
public class TestEntityLine implements Serializable {
    @Id
    @Column
    private Long id;

    @JoinColumn(name = "PID", referencedColumnName = "ID", nullable = true)
    private TestEntity testEntity;
}

sql和结果日志：

   String boql = "SELECT e FROM TestEntity e order by e.id";
   query.setFirstResult(1); // for pagination
   query.setMaxResults(3); // for pagination

所有这些都很完美。但是当我启用多租户时：

2016-06-16 10:05:14.558 [main] DEBUG o.e.p.s./.sql - SELECT ID AS a1 FROM TESTENTITY ORDER BY ID LIMIT ? OFFSET ?
    bind => [3, 1]
entity-2
2016-06-16 10:05:14.594 [main] DEBUG o.e.p.s./.sql - SELECT ID, NAME, VALUE, PID FROM TESTENTITYLINE WHERE (PID IN (?,?,?))
    bind => [2, 3, 4]
entityLine-2-3
entityLine-2-1
entityLine-2-2
entity-3
entityLine-3-2
entityLine-3-1
entityLine-3-3
entity-4
entityLine-4-3
entityLine-4-2
entityLine-4-1

当我使用：

查询时

String boql =＆＃34; SELECT e FROM TestEntity e order by e.id＆＃34 ;; query.setFirstResult（1）; //用于分页 query.setMaxResults（3）; //用于分页

sql和结果日志：

@Entity
public class TestMultiTenantEntity implements Serializable {
    @Id
    @Column
    private Long id;

    @OneToMany(mappedBy = "testEntity", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    @BatchFetch(BatchFetchType.IN)
    private List<TestMultiTenantEntityLine> lines = new ArrayList<>();
}

@Entity
public class TestMultiTenantEntityLine implements Serializable {
    @Id
    @Column
    private Long id;

    @JoinColumn(name = "PID", referencedColumnName = "ID", nullable = true)
    private TestMultiTenantEntity testEntity;
}

@MappedSuperclass
@Multitenant(SINGLE_TABLE)
@TenantDiscriminatorColumn(discriminatorType = DiscriminatorType.INTEGER, primaryKey = true, name = MultiTenantSupport.TENANT_COLUMN_NAME, length = 12, contextProperty = MultiTenantSupport.MULTITENANT_CONTEXT_PROPERTY)
public abstract class MultiTenantSupport {

    public static final String MULTITENANT_CONTEXT_PROPERTY = "tenant_id";

    public static final String TENANT_COLUMN_NAME = "TENANT_ID";

}

为什么TESTMULTITENANTENTITYLINE会自行加入t0 / t1？这会产生许多重复的记录

我尝试获取记录2,3,4，为什么它取出1,5,6？

你可以帮忙吗？这是一个错误吗？或者我错过了什么？提前谢谢。

Answer 1

通过以下设置从主键中删除tenant_id后，它可以正常工作：

@TenantDiscriminatorColumn(primaryKey = false, ...)

但是，尽管我不需要它们，但是JOIN和EXIST选项不起作用。它看起来在JOIN和EXIST sql中所需的pid不包含在where条件中。这就是为什么它加载所有其他不需要的条目

eclipselink批量提取IN对多租户不起作用

1 个答案: