Re-jigged the class implementation to get better support from roxygen2 and CRAN check(). Majority of public functions are documented (remaining are the CRUD functions)

man/DBClient-cash-withTransaction.Rd

@@ -0,0 +1,14 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/DBClient-dbTransaction.R
+\name{DBClient$withTransaction}
+\alias{DBClient$withTransaction}
+\title{DBClient$withTransaction}
+\arguments{
+\item{expr}{\if{html}{\out{<expression>}} Expression to run in a transaction}
+}
+\value{
+\if{html}{\out{<logical>}} TRUE if transaction was successful
+}
+\description{
+Runs a given expression within a database transaction.
+}