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What is the Hibernate equivalent of "select 1 from DUAL"?

What is the minimum sleep request? Is there an equivalent to "choose 1 from DUAL" for Hibernate?

I am writing a healthcheck function and would like to execute a minimal query, but use HQL to keep the code portable (as opposed to using my own query).

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dialects of hibernation - this is what is translated into various databases, and there is no support for "health checks" or "checks" on dialects. This usually happens with a pool of connections, rather than sleeping. See, for example, DBCP Validation Validation Property .

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SQL is select 1 from DUAL;not a good health check, the only thing you see is the server response, which does not mean that the data itself is healthy. But if you want to ask such a question, just create your own data object that mimics DUAL, and you control the object, and you will remain common to any DBMS.

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@Entity
@Table(name="myDual")
public class MyDual implements Serializable {

  @Id
  @Column(name = "id")
  Integer id;

  public Integer getId() {
    return id;
  }

  public void setId(Integer id) {
    this.id = id;
  }

}

CacheMode.IGNORE CacheMode.REFRESH . , ...

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SQL- . - session.createSQLQuery("Select 1 from dual").uniqueResult();

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session.createQuery("select 1 from existingTable").setMaxResults(1).uniqueResult();
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Hmm, , 1 dual , . ANSI information_schema , , DB, , , .

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DUAL hibernate

session.createSQLQuery("SELECT 1 from DUAL") 


session.createQuery("SELECT 1 from DUAL").
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