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<HTML><HEAD><META http-equiv="Content-Type" content="text/html; charset=UTF-8"><TITLE>Perst.TransactionMode</TITLE><LINK REL=STYLESHEET HREF="../CommentReport.css" TYPE="text/css"></HEAD><BODY topmargin=0 rightmargin=0 leftmargin=0 style="background-image: url(../titletile.jpg); background-repeat:repeat-x; background-position: 0 0;" ><DIV CLASS="PageHeading">Perst.TransactionMode Enum</DIV><DIV CLASS="Description"></DIV><IMG src="../GradLeft.jpg" width=7 height=378 alt="" border="0" style="position:absolute; left:10; top:18;z-Index:2"><IMG src="../GradTop.jpg" width=352 height=7 alt="" border="0" align="top" style="position:absolute; left:10; top:18; z-index:1"><DIV CLASS="Remarks"><SPAN CLASS="RemarkHdrX">Access: </SPAN>Public</DIV><TABLE CLASS="InfoTable" cellpadding=0 cellspacing=0><TR height=20><TD width=20> </TD><TD valign=top align=left width=9 bgcolor="#cccc66"><IMG SRC="../graycorner.jpg" align=top></TD><TD CLASS="TableLightLabel" WIDTH=206>Members</TD><TD CLASS="TableLightLabel" >Description</TD><TD width=20> </TD></TR><TR height=20><TD width=20> </TD><TD CLASS="TableLightDesc"> </TD><TD CLASS="TableLightDesc"><A HREF="CWP4320.HTM" TARGET="CNTFRAME">Exclusive</A></TD><TD CLASS="TableLightDesc">
Exclusive per-thread transaction: each thread access database in exclusive mode
<P></TD><TD width=20> </TD></TR><TR height=20><TD width=20> </TD><TD CLASS="TableLightDesc"> </TD><TD CLASS="TableLightDesc"><A HREF="CWP4321.HTM" TARGET="CNTFRAME">Cooperative</A></TD><TD CLASS="TableLightDesc">
Cooperative mode; all threads share the same transaction. Commit will commit changes made
by all threads. To make this schema work correctly, it is necessary to ensure (using locking)
that no thread is performing update of the database while another one tries to perform commit.
Also please notice that rollback will undo the work of all threads.
<P></TD><TD width=20> </TD></TR><TR height=20><TD width=20> </TD><TD CLASS="TableLightDesc"> </TD><TD CLASS="TableLightDesc"><A HREF="CWP4322.HTM" TARGET="CNTFRAME">Serializable</A></TD><TD CLASS="TableLightDesc">
Serializable per-thread transaction. Unlike exclusive mode, threads can concurrently access database,
but effect will be the same as them work exclusively.
To provide such behavior, programmer should lock all access objects (or use hierarchical locking).
When object is updated, exclusive lock should be set, otherwise shared lock is enough.
Lock should be preserved until the end of transaction.
<P></TD><TD width=20> </TD></TR><TR height=20><TD width=20> </TD><TD CLASS="TableLightDesc"> </TD><TD CLASS="TableLightDesc"><A HREF="CWP4323.HTM" TARGET="CNTFRAME">ReplicationSlave</A></TD><TD CLASS="TableLightDesc">
Read only transaction which can be started at replicastion slave node.
It runs concurrently with receiving updates from master node.
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