Question

我遇到以下Hibernate TypedQuery的性能问题：

select generatedAlias0 from MyClass1 as generatedAlias0
where generatedAlias0.class2.uid in (:param0, ..., :paramN)

在实际实施之后，会产生以下查询：

select myclass1_.id, myclass1_.other, ... # 16 fields in total, no special big ones
from myschema.dbo.TblMyClass1 myclass1_ cross join myschema.dbo.TblMyClass2 myclass2_
where myclass1_.myclass2Id=myclass2.Id and (myclass2_.uid in('value1', ... 'valueN'))

其中N每次代表384项。

当我在Toad中执行此查询时，它只需要大约150毫秒，但是从代码执行它需要将近一分钟！

类映射

@Entity
@Table(name = "TblMyClass1", catalog = "myschema", schema = "dbo")
public class MyClass1 implements Serializable {

private static final long serialVersionUID = 8208493383744288872L;

@Id
@Column(name = "Id")
@GeneratedValue(strategy = GenerationType.AUTO)
protected Integer id;

@NotNull
@ManyToOne
@JoinColumn(name = "myclass2Id", referencedColumnName = "Id", nullable = false)
private MyClass2 class2 = null;

@NotNull
@ManyToOne
@JoinColumn(name = "myclass3Id", referencedColumnName = "Id", nullable = false)
private MyClass3 class3 = null;

@NotNull
@ManyToOne
@JoinColumn(name = "myClass4Id", referencedColumnName = "Id", nullable = false)
private MyClass4 myClass4;

@ManyToOne
@JoinColumn(name = "myClass5Uid", referencedColumnName = "UID", nullable = true)
private MyClass5 resultType;

@Column(name = "string2", nullable = true)
private String string2;

// other column fields and getters and setters ... 
}

@Entity
@Table(name = "TblMyClass2", schema = "myschema", catalog = "dbo")
public final class MyCLass2 implements Serializable {

private static final long serialVersionUID = 4660579327140751989L;

@Id
@Column(name = "Id")
@GeneratedValue(strategy = GenerationType.AUTO)
protected Integer id;

@Column(name = "uid", nullable = false, updatable = false, unique = true)
private String uid;

// ... other columns fields and getters and setters
}

我只在慢速查询中提供了两个类的映射，因为hibernate的后续查询填充了所有其他链接实体，都表现得非常好。

使用Java VisualVm我发现以下方法占用了99％的时间：

com.microsoft.sqlserver.jdbc.TDSChannel.read()

我正在运行 SQL Server 2008 并使用 sqljdbc4-2.0 和 hibernate4.2.1 与 spring3.2.9 （用于交易管理）

非常感谢任何帮助！

Hibernate与SqlServer性能下降选择

0 个答案: