Description of the illustration strms049.eps
This illustration shows messages being enqueued and browsed within a database. Two sessions are enqueuing messages in the following sequence:
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Session 1 enqueues message e1 as part of transaction T1.
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Session 2 enqueues message e2 as part of transaction T2.
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Session 1 enqueues message e3 as part of transaction T1.
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Session 2 commits transaction T2.
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Session 1 commits transaction T1.
Session 3 browses messages in the queue at two different times. The first time session 3 browses messages, session 2 has committed, but session 1 has not yet committed. For this browse, the browse set shows messages in the following order:
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e2
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e1
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e3
The second time session 3 browses messages, both session 1 and session 2 have committed. For this browse, the browse set shows messages in the following order:
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e1
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e3
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e2