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<title>Berkeley DB: DB_TXN</title>
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typedef struct __db_txn DB_TXN;
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<p>The DB_TXN object is the handle for a transaction. Methods off
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the DB_TXN handle are used to configure, abort and commit the
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transaction. DB_TXN handles are provided to <a href="../api_c/db_class.html">DB</a> methods
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in order to transactionally protect those database operations.
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<p>DB_TXN handles are not free-threaded; transactions handles may
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be used by multiple threads, but only serially, that is, the application
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must serialize access to the DB_TXN handle. Once the
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<a href="../api_c/txn_abort.html">DB_TXN->abort</a> or <a href="../api_c/txn_commit.html">DB_TXN->commit</a> methods are called, the handle may
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not be accessed again, regardless of the method's return. In addition,
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parent transactions may not issue any Berkeley DB operations while they have
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active child transactions (child transactions that have not yet been
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committed or aborted) except for <a href="../api_c/txn_begin.html">DB_ENV->txn_begin</a>, <a href="../api_c/txn_abort.html">DB_TXN->abort</a>
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and <a href="../api_c/txn_commit.html">DB_TXN->commit</a>.
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<a href="../api_c/env_class.html">DB_ENV</a>, DB_TXN
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<a href="../api_c/txn_list.html">Transaction Subsystem and Related Methods</a>
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