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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/dbExistsTable.R
\name{dbExistsTable}
\alias{dbExistsTable}
\title{Does a table exist?}
\usage{
dbExistsTable(conn, name, ...)
}
\arguments{
\item{conn}{A \link[=DBIConnection-class]{DBI::DBIConnection} object,
as returned by \code{\link[=dbConnect]{dbConnect()}}.}
\item{name}{The table name, passed on to \code{\link[=dbQuoteIdentifier]{dbQuoteIdentifier()}}. Options are:
\itemize{
\item a character string with the unquoted DBMS table name,
e.g. \code{"table_name"},
\item a call to \code{\link[=Id]{Id()}} with components to the fully qualified table name,
e.g. \code{Id(schema = "my_schema", table = "table_name")}
\item a call to \code{\link[=SQL]{SQL()}} with the quoted and fully qualified table name
given verbatim, e.g. \code{SQL('"my_schema"."table_name"')}
}}
\item{...}{Other parameters passed on to methods.}
}
\value{
\code{dbExistsTable()} returns a logical scalar, \code{TRUE} if the table or view
specified by the \code{name} argument exists, \code{FALSE} otherwise.
This includes temporary tables if supported by the database.
}
\description{
Returns if a table given by name exists in the database.
\Sexpr[results=rd,stage=render]{DBI:::methods_as_rd("dbExistsTable")}
}
\section{Failure modes}{
An error is raised when calling this method for a closed
or invalid connection.
An error is also raised
if \code{name} cannot be processed with \code{\link[DBI:dbQuoteIdentifier]{DBI::dbQuoteIdentifier()}} or
if this results in a non-scalar.
}
\section{Specification}{
The \code{name} argument is processed as follows,
to support databases that allow non-syntactic names for their objects:
\itemize{
\item If an unquoted table name as string: \code{dbExistsTable()} will do the
quoting,
perhaps by calling \code{dbQuoteIdentifier(conn, x = name)}
\item If the result of a call to \code{\link[DBI:dbQuoteIdentifier]{DBI::dbQuoteIdentifier()}}: no more quoting is done
}
For all tables listed by \code{\link[DBI:dbListTables]{DBI::dbListTables()}}, \code{dbExistsTable()} returns \code{TRUE}.
}
\examples{
\dontshow{if (requireNamespace("RSQLite", quietly = TRUE)) withAutoprint(\{ # examplesIf}
con <- dbConnect(RSQLite::SQLite(), ":memory:")
dbExistsTable(con, "iris")
dbWriteTable(con, "iris", iris)
dbExistsTable(con, "iris")
dbDisconnect(con)
\dontshow{\}) # examplesIf}
}
\seealso{
Other DBIConnection generics:
\code{\link{DBIConnection-class}},
\code{\link{dbAppendTable}()},
\code{\link{dbAppendTableArrow}()},
\code{\link{dbCreateTable}()},
\code{\link{dbCreateTableArrow}()},
\code{\link{dbDataType}()},
\code{\link{dbDisconnect}()},
\code{\link{dbExecute}()},
\code{\link{dbGetException}()},
\code{\link{dbGetInfo}()},
\code{\link{dbGetQuery}()},
\code{\link{dbGetQueryArrow}()},
\code{\link{dbIsReadOnly}()},
\code{\link{dbIsValid}()},
\code{\link{dbListFields}()},
\code{\link{dbListObjects}()},
\code{\link{dbListResults}()},
\code{\link{dbListTables}()},
\code{\link{dbQuoteIdentifier}()},
\code{\link{dbReadTable}()},
\code{\link{dbReadTableArrow}()},
\code{\link{dbRemoveTable}()},
\code{\link{dbSendQuery}()},
\code{\link{dbSendQueryArrow}()},
\code{\link{dbSendStatement}()},
\code{\link{dbUnquoteIdentifier}()},
\code{\link{dbWriteTable}()},
\code{\link{dbWriteTableArrow}()}
}
\concept{DBIConnection generics}
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