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eclipselinkmulti-tenantbatch-fetching

eclipselink batch fetch IN does not work well with multiple tenant

I am using @Multitenant(SINGLE_TABLE) to support multi-tenancy. To fix the n+1 problem, I use batch fetch feature of eclipselink.

@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;
}

When I query using:

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

The sql and results log:

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

All of these works perfectly. But when I enable multi-tenant:

@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";

}

When I query using:

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

The sql and results log:

2016-06-16 10:17:17.123 [main] DEBUG o.e.p.s./.sql - SELECT TENANT_ID AS a1, ID AS a2 FROM TESTMULTITENANTENTITY WHERE (TENANT_ID = ?) ORDER BY ID LIMIT ? OFFSET ?
    bind => [1, 3, 1]
entity-2
2016-06-16 10:17:17.159 [main] DEBUG o.e.p.s./.sql - SELECT t0.TENANT_ID, t0.ID, t0.NAME, t0.VALUE, t0.PID FROM TESTMULTITENANTENTITYLINE t0, TESTMULTITENANTENTITYLINE t1 WHERE ((((t1.TENANT_ID, t1.PID) IN ((?,?),(?,?),(?,?))) AND (t0.TENANT_ID = ?)) AND (t1.TENANT_ID = ?))
    bind => [1, 2, 1, 3, 1, 4, 1, 1]  **?????? Why TESTMULTITENANTENTITYLINE joins to itself t0/t1? This produce many duplicated records**
2016-06-16 10:17:17.227 [main] DEBUG o.e.p.s./.sql - SELECT TENANT_ID, ID FROM TESTMULTITENANTENTITY WHERE (((TENANT_ID = ?) AND (ID = ?)) AND (TENANT_ID = ?))
    bind => [1, 1, 1] **?????? I try to fetch record 2,3,4, why it fetch out 1, 5, 6?**
2016-06-16 10:17:17.267 [main] DEBUG o.e.p.s./.sql - SELECT TENANT_ID, ID FROM TESTMULTITENANTENTITY WHERE (((TENANT_ID = ?) AND (ID = ?)) AND (TENANT_ID = ?))
    bind => [1, 5, 1]
2016-06-16 10:17:17.295 [main] DEBUG o.e.p.s./.sql - SELECT TENANT_ID, ID FROM TESTMULTITENANTENTITY WHERE (((TENANT_ID = ?) AND (ID = ?)) AND (TENANT_ID = ?))
    bind => [1, 6, 1]
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-1
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-2
entityLine-2-3
entityLine-2-3
entityLine-2-3
entityLine-2-3
entityLine-2-3
entityLine-2-3
entityLine-2-3
entityLine-2-3
entityLine-2-3
entity-3
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-1
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-2
entityLine-3-3
entityLine-3-3
entityLine-3-3
entityLine-3-3
entityLine-3-3
entityLine-3-3
entityLine-3-3
entityLine-3-3
entityLine-3-3
entity-4
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-1
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-2
entityLine-4-3
entityLine-4-3
entityLine-4-3
entityLine-4-3
entityLine-4-3
entityLine-4-3
entityLine-4-3
entityLine-4-3
entityLine-4-3

Why TESTMULTITENANTENTITYLINE joins to itself t0/t1? This produce many duplicated records

I try to fetch record 2,3,4, why it fetch out 1, 5, 6?

Could you please help? is this a bug? Or I missed something? Thanks in advance.

Solution

  • It works after I removed tenant_id from the primary key by the following setting:

    @TenantDiscriminatorColumn(primaryKey = false, ...)

    But still, JOIN and EXIST option does not work although I do not need them. It looks that in JOIN and EXIST sql the needed pids are not included in the where condition. and that's why it loads all other unneeded entries