lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Terry Steichen" <>
Subject Re: auto-generate uid?
Date Mon, 22 Nov 2004 22:14:33 GMT
Not exactly sure what you're trying to do.  You can easily generate a number when you index
each Document and insert it in a uid field (which is, BTW, what I do), and if you base it
on a timestamp plus some characteristic of the document (which is also what I do), it should
always be unique.  As you add more documents, they will each get their own unique id.  When
you delete documents and optimize, these ids won't be affected.

However, in your subsequent clarification, you indicated you already had a unique id, and
want to find the maximum value.  So why did you say you want one auto-generated?

  ----- Original Message ----- 
  From: aurora 
  Sent: Monday, November 22, 2004 4:39 PM
  Subject: Re: auto-generate uid?

  Just to clarify. I have a Field 'uid' those value is an unique integer. I  
  use it as a key to the document stored externally. I don't mean Lucene's  
  internal document number.

  I was wonder if there is a method to query the highest value of a field,  
  perhaps something like:


  > What would the purpose of an auto-generated UID be?
  > But no, Lucene does not generate UID's for you.  Documents are numbered  
  > internally by their insertion order.  This number changes, however, when  
  > documents are deleted in the middle and the index is optimized.
  > Erik
  > On Nov 22, 2004, at 1:50 PM, aurora wrote:
  >> Is there a way to auto-generate uid in Lucene? Even it is just a way to  
  >> query the highest uid and let the application add one to it will do.
  >> Thanks.
  >> ---------------------------------------------------------------------
  >> To unsubscribe, e-mail:
  >> For additional commands, e-mail:

  Using Opera's revolutionary e-mail client:

  To unsubscribe, e-mail:
  For additional commands, e-mail:

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message