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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/spec-transaction-begin-commit-rollback.R
\docType{data}
\name{spec_transaction_begin_commit_rollback}
\alias{spec_transaction_begin_commit_rollback}
\title{spec_transaction_begin_commit_rollback}
\value{
\code{dbBegin()}, \code{dbCommit()} and \code{dbRollback()} return \code{TRUE}, invisibly.
}
\description{
spec_transaction_begin_commit_rollback
}
\section{Failure modes}{
The implementations are expected to raise an error in case of failure,
but this is not tested.
In any way, all generics throw an error with a closed
or invalid connection.
In addition, a call to \code{dbCommit()}
or \code{dbRollback()}
without a prior call to \code{dbBegin()} raises an error.
Nested transactions are not supported by DBI,
an attempt to call \code{dbBegin()} twice
yields an error.
}
\section{Specification}{
Actual support for transactions may vary between backends.
A transaction is initiated by a call to \code{dbBegin()}
and committed by a call to \code{dbCommit()}.
Data written in a transaction must persist after the transaction is committed.
For example, a record that is missing when the transaction is started
but is created during the transaction
must exist
both during
and after the transaction,
and also in a new connection.
A transaction
can also be aborted with \code{dbRollback()}.
All data written in such a transaction must be removed after the
transaction is rolled back.
For example, a record that is missing when the transaction is started
but is created during the transaction
must not exist anymore after the rollback.
Disconnection from a connection with an open transaction
effectively rolls back the transaction.
All data written in such a transaction must be removed after the
transaction is rolled back.
The behavior is not specified if other arguments are passed to these
functions. In particular, \pkg{RSQLite} issues named transactions
with support for nesting
if the \code{name} argument is set.
The transaction isolation level is not specified by DBI.
}
\seealso{
Other transaction specifications:
\code{\link{spec_transaction_with_transaction}}
}
\concept{transaction specifications}
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