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POHibernate: How do I write the HQL for getting records of an entity without records for its identifying relation
 

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  1. POHibernate: How do I write the HQL for getting records of an entity without records for its identifying relation
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    <p>I have Hibernate Objects defined as </p> <pre><code>Class SomeText{ private Long textId; private Set&lt;Tag&gt; Tags = new HashSet&lt;Tag&gt;(); @ManyToMany(cascade={CascadeType.PERSIST,CascadeType.MERGE }) @JoinTable(name = "text_tag_reln", joinColumns = { @JoinColumn(name = "textId") }, inverseJoinColumns = { @JoinColumn(name = "tagId") }) public Set&lt;Tag&gt; getTags() { return Tags; } } Class Tag{ private long tagId; } </code></pre> <p>I now want to get all those SomeText objects that do not have any Tags. I wrote the following HQL but it doesn't work.</p> <pre><code>select st from SomeText as st where st.Tags = null </code></pre> <p>What do I do to get these records. In the SQL world, I would have written a query which would get all distinct textIds from the text_tag_reln table and get all SomeText ids that weren't present in that set. How can I do this in HQL?</p>
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    1. USRitesh M Nayak
    1. USRitesh M Nayak
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    1. This table or related slice is empty.
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      1. POHibernate: How do I write the HQL for getting records of an entity without records for its identifying relation
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    1. COyou set Tags to new HashSet<Tag>() when you create the object, how could it ever be null?
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      1. POHibernate: How do I write the HQL for getting records of an entity without records for its identifying relation
      1. USAaron Saunders
 

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