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Viewing changes to server/item_func.cc

  • Committer: mark
  • Date: 2008-07-13 01:49:20 UTC
  • mto: This revision was merged to the branch mainline in revision 142.
  • Revision ID: mark@piggy.tangent.org-20080713014920-0m6zrvbzaext73ij
remove UUID_SHORT()

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Lines of Context:
server/item_func.cc
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  return thd->found_rows();
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}
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/*
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  uuid_short handling.
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  The short uuid is defined as a longlong that contains the following bytes:
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  Bytes  Comment
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  1      Server_id & 255
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  4      Startup time of server in seconds
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  3      Incrementor
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  This means that an uuid is guaranteed to be unique
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  even in a replication environment if the following holds:
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  - The last byte of the server id is unique
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  - If you between two shutdown of the server don't get more than
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    an average of 2^24 = 16M calls to uuid_short() per second.
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*/
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ulonglong uuid_value;
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void uuid_short_init()
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{
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  uuid_value= ((((ulonglong) server_id) << 56) + 
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               (((ulonglong) server_start_time) << 24));
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}
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longlong Item_func_uuid_short::val_int()
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{
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  ulonglong val;
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  pthread_mutex_lock(&LOCK_uuid_generator);
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  val= uuid_value++;
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  pthread_mutex_unlock(&LOCK_uuid_generator);
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  return (longlong) val;
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}