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    copied!<p>There is the article at the link below about implementing custom identity generator (see: <strong>Part 1: Inheriting from TableGenerator class</strong>) but the example throws the exception for SQLite database (<strong>"SQLite errorr no such table: hibernate_unique_key"</strong>). Thus as regard SQLite there is no possibility to gain current id key from a table. It uses class <strong>TableGenerator</strong> from NHibernate API (NHibernate.Id);</p> <p><a href="http://nhforge.org/wikis/howtonh/creating-a-custom-id-generator-for-nhibernate.aspx" rel="nofollow">http://nhforge.org/wikis/howtonh/creating-a-custom-id-generator-for-nhibernate.aspx</a></p> <p>To avoid the exception I implemented another solution (especially the way of getting current Id). It takes advantage of Fluent-NHibernate API (<strong>GeneratedBy.Custom()</strong>). Look at the following source code:</p> <pre><code>public class MyAutoincrement&lt;T&gt; : IIdentifierGenerator where T : IId { #region IIdentifierGenerator Members public object Generate(ISessionImplementor session, object obj) { NHibernate.ISession s = (NHibernate.ISession)session; int seedValue = 1000; int maxId = -1;//start autoincrement from zero! (fluent nhibernate start from 1 as default) List&lt;T&gt; recs = s.Query&lt;T&gt;().ToList&lt;T&gt;(); if (recs.Count &gt; 0) { maxId = recs.Max(x =&gt; x.getId()); } return seedValue + maxId + 1; } #endregion } //Interface for access to current Id of table public interface IId { int getId(); } //Entity public class MyEntity : IId { public virtual int Id { get; protected set; } public virtual string MyField1 { get; set; } public virtual string MyField2 { get; set; } #region IId Members public virtual int getId() { return this.Id; } #endregion } //Entity Mapping public class MyEntityMap : ClassMap&lt;MyEntity&gt; { public MyEntityMap() { Id(x =&gt; x.Id).GeneratedBy.Custom&lt;MyAutoincrement&lt;MyEntity&gt;&gt;(); Map(x =&gt; x.MyField1); Map(x =&gt; x.MyField1); } } </code></pre> <p>It works with SQLite database and involves custom identity seed.</p> <p>Regards Bronek</p>
 

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