Mixing transactional and nontransactional statements within the same transaction-opracowanie

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Mixing transactional and nontransactional statements within the same transaction-opracowanie - strona 1

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Mixing transactional and nontransactional statements within the same transaction. In
general, you should avoid transactions that update both transactional and nontransactional tables in a
replication environment. You should also avoid using any statement that accesses both transactional
(or temporary) and nontransactional tables and writes to any of them.
As of MySQL 5.5.2, the server uses these rules for binary logging:
• If the initial statements in a transaction are nontransactional, they are written to the binary log
immediately. The remaining statements in the transaction are cached and not written to the binary
log until the transaction is committed. (If the transaction is rolled back, the cached statements are
written to the binary log only if they make nontransactional changes that cannot be rolled back.
Otherwise, they are discarded.)
• For statement-based logging, logging of nontransactional statements is affected by the
binlog_direct_non_transactional_updates [2046] system variable. When this variable
is OFF (the default), logging is as just described. When this variable is ON, logging occurs
immediately for nontransactional statements occurring anywhere in the transaction (not just initial
nontransactional statements). Other statements are kept in the transaction cache and logged when
the transaction commits. binlog_direct_non_transactional_updates [2046] has no effect
for row-format or mixed-format binary logging.
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