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71 lines
2.6 KiB
C++
71 lines
2.6 KiB
C++
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/* Definition of the pqxx::dbtransaction abstract base class.
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*
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* pqxx::dbransaction defines a real transaction on the database.
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*
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* DO NOT INCLUDE THIS FILE DIRECTLY; include pqxx/dbtransaction instead.
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*
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* Copyright (c) 2000-2022, Jeroen T. Vermeulen.
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*
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* See COPYING for copyright license. If you did not receive a file called
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* COPYING with this source code, please notify the distributor of this
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* mistake, or contact the author.
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*/
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#ifndef PQXX_H_DBTRANSACTION
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#define PQXX_H_DBTRANSACTION
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#if !defined(PQXX_HEADER_PRE)
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# error "Include libpqxx headers as <pqxx/header>, not <pqxx/header.hxx>."
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#endif
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#include "pqxx/transaction_base.hxx"
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namespace pqxx
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{
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/// Abstract transaction base class: bracket transactions on the database.
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/**
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* @ingroup transactions
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*
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* Use a dbtransaction-derived object such as "work" (transaction<>) to enclose
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* operations on a database in a single "unit of work." This ensures that the
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* whole series of operations either succeeds as a whole or fails completely.
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* In no case will it leave half-finished work behind in the database.
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*
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* Once processing on a transaction has succeeded and any changes should be
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* allowed to become permanent in the database, call commit(). If something
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* has gone wrong and the changes should be forgotten, call abort() instead.
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* If you do neither, an implicit abort() is executed at destruction time.
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*
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* It is an error to abort a transaction that has already been committed, or to
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* commit a transaction that has already been aborted. Aborting an already
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* aborted transaction or committing an already committed one is allowed, to
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* make error handling easier. Repeated aborts or commits have no effect after
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* the first one.
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*
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* Database transactions are not suitable for guarding long-running processes.
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* If your transaction code becomes too long or too complex, consider ways to
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* break it up into smaller ones. Unfortunately there is no universal recipe
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* for this.
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*
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* The actual operations for committing/aborting the backend transaction are
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* implemented by a derived class. The implementing concrete class must also
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* call @ref close from its destructor.
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*/
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class PQXX_LIBEXPORT PQXX_NOVTABLE dbtransaction : public transaction_base
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{
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protected:
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/// Begin transaction.
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explicit dbtransaction(connection &c) : transaction_base{c} {}
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/// Begin transaction.
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dbtransaction(connection &c, std::string_view tname) :
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transaction_base{c, tname}
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{}
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/// Begin transaction.
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dbtransaction(
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connection &c, std::string_view tname,
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std::shared_ptr<std::string> rollback_cmd) :
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transaction_base{c, tname, rollback_cmd}
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{}
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};
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} // namespace pqxx
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#endif
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