Sophie: postgresql9.4-docs-9.4.15-1.mga6 noarch

postgresql9.4-docs-9.4.15-1.mga6.noarch.rpm

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>    Some DDL commands, currently only <A
HREF="sql-truncate.html"
>TRUNCATE</A
> and the
    table-rewriting forms of <A
HREF="sql-altertable.html"
>ALTER TABLE</A
>, are not
    MVCC-safe.  This means that after the truncation or rewrite commits, the
    table will appear empty to concurrent transactions, if they are using a
    snapshot taken before the DDL command committed.  This will only be an
    issue for a transaction that did not access the table in question
    before the DDL command started &mdash; any transaction that has done so
    would hold at least an <TT
CLASS="LITERAL"
>ACCESS SHARE</TT
> table lock,
    which would block the DDL command until that transaction completes.
    So these commands will not cause any apparent inconsistency in the
    table contents for successive queries on the target table, but they
    could cause visible inconsistency between the contents of the target
    table and other tables in the database.
   </P
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>    Support for the Serializable transaction isolation level has not yet
    been added to Hot Standby replication targets (described in
    <A
HREF="hot-standby.html"
>Section 25.5</A
>).  The strictest isolation level currently
    supported in hot standby mode is Repeatable Read.  While performing all
    permanent database writes within Serializable transactions on the
    master will ensure that all standbys will eventually reach a consistent
    state, a Repeatable Read transaction run on the standby can sometimes
    see a transient state that is inconsistent with any serial execution
    of the transactions on the master.
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