Transactional nontransactional and mixed statements-opracowanie

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Transactional nontransactional and mixed statements.
To apply those rules, the server considers a statement nontransactional if it changes only
nontransactional tables, and transactional if it changes only transactional tables. In MySQL 5.6, a
statement that references both nontransactional and transactional tables and updates any of the tables
involved, is considered a “mixed” statement. (In previous MySQL release series, a statement that
changed both nontransactional and transactional tables was considered mixed.) Mixed statements, like
transactional statements, are cached and logged when the transaction commits.
A mixed statement that updates a transactional table is considered unsafe if the statement also
performs either of the following actions:
• Updates or reads a transactional table
• Reads a nontransactional table and the transaction isolation level is less than REPEATABLE_READ
A mixed statement following the update of a transactional table within a transaction is considered
unsafe if it performs either of the following actions
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