question about deadlock in oracle RSS

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  aoshi_kh

  Member

  123 Points

  331 Posts

  question about deadlock in oracle

  Aug 19, 2012 03:30 AM|LINK

  First time use oracle and toad, hope someone can help me this... when select data from few table, will it cause deadlock if other people also using the table at the same time? how can preven deadlock when select data in oracle database using toad?
  • Edited by aoshi_kh on Aug 19, 2012 03:36 AM
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  Lannie

  Contributor

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  748 Posts

  Re: question about deadlock in oracle

  Aug 19, 2012 09:23 PM|LINK

  No locks on SELECT data.

  Row lock on INSERT, UPDATE, DELETE in progress.

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  Ajay2707

  Contributor

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  966 Posts

  Re: question about deadlock in oracle

  Aug 24, 2012 06:12 AM|LINK

  Hi Aoshi_kh,

  As lannie said, by default No lock in select data. you don't need nolock with Oracle.

  SELECT  SUM(LEN(name))
  FROM    master WITH (NOLOCK)

  But when update cluase with select statement it create lock temporary.

  normal select -- no lock
  insert , update , delete , select for update -- lock

  see more for how to lock work.

  http://stackoverflow.com/questions/1682240/what-can-happen-as-a-result-of-using-nolock-on-every-select-in-sql-sever

  http://broadh2o.net/docs/database/oracle/oracleLocks.html

  Please, Mark as Answer if this reply helped you.
  • Marked as answer by haixia xie - msft on Sep 10, 2012 12:05 PM