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Use the :requires_new option for nested transactions #9
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Nested transactions are not really supported at the database level. Because of this, nesting transaction blocks can cause the outer block to be aborted which will cause later SQL statements to fail with the message: PG::InFailedSqlTransaction: ERROR: current transaction is aborted, commands ignored until end of transaction block This is currently the case with the buffered_committer's 1000 change transaction and the one started in the attempt_change method in the OneWayReplicator. To deal with this the PostgreSQLAdapter#transaction method accepts a `requires_new` option which uses save points to simulate nested transactions. This change adds this option to the previously nested transaction in the OneWayReplicator This will allow for the insert to fail (for example with a unique constraint error) and the outer transaction to continue. More information about this option can be found at: http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/DatabaseStatements.html#method-i-transaction
Fryguy
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Jun 30, 2016
…action Use the :requires_new option for nested transactions (cherry picked from commit 97d5f9a)
carbonin
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This was required because rubyrep would open a transaction per 1000 rows and also a transaction for each change it replicated. If the inner transaction failed for any reason, the outer transaction would also be aborted because postgresql does not really support nested transactions. This would cause the replicate process to timeout because no sql could then be processed in the aborted transaction. ManageIQ/rubyrep#9 https://bugzilla.redhat.com/show_bug.cgi?id=1348576
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Nested transactions are not really supported at the database level.
Because of this, nesting transaction blocks can cause the outer block to be aborted which will cause later SQL statements to fail with the message:
This is currently the case with the
BufferedCommitter's 1000 change transaction and the one started in the attempt_change method in theOneWayReplicator.To deal with this the
PostgreSQLAdapter#transactionmethod accepts a:requires_newoption which uses save points to simulate nested transactions.This change adds this option to the previously nested transaction in the
OneWayReplicatorThis will allow for the insert to fail (for example with a unique constraint error) and the outer transaction to continue.
More information about this option can be found at:
http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/DatabaseStatements.html#method-i-transaction
Worked on this with @gtanzillo
https://bugzilla.redhat.com/show_bug.cgi?id=1348576