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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/deprecated.R, R/isSQLKeyword.R,
% R/make.db.names.R
\name{make.db.names.default}
\alias{make.db.names.default}
\alias{isSQLKeyword.default}
\alias{isSQLKeyword}
\alias{make.db.names}
\alias{SQLKeywords}
\title{Make R identifiers into legal SQL identifiers}
\usage{
make.db.names.default(
snames,
keywords = .SQL92Keywords,
unique = TRUE,
allow.keywords = TRUE
)
isSQLKeyword.default(
name,
keywords = .SQL92Keywords,
case = c("lower", "upper", "any")[3]
)
isSQLKeyword(
dbObj,
name,
keywords = .SQL92Keywords,
case = c("lower", "upper", "any")[3],
...
)
make.db.names(
dbObj,
snames,
keywords = .SQL92Keywords,
unique = TRUE,
allow.keywords = TRUE,
...
)
}
\arguments{
\item{snames}{a character vector of R identifiers (symbols) from which we
need to make SQL identifiers.}
\item{keywords}{a character vector with SQL keywords, by default it's
\code{.SQL92Keywords} defined by the DBI.}
\item{unique}{logical describing whether the resulting set of SQL names
should be unique. Its default is \code{TRUE}. Following the SQL 92
standard, uniqueness of SQL identifiers is determined regardless of whether
letters are upper or lower case.}
\item{allow.keywords}{logical describing whether SQL keywords should be
allowed in the resulting set of SQL names. Its default is \code{TRUE}}
\item{name}{a character vector with database identifier candidates we need
to determine whether they are legal SQL identifiers or not.}
\item{case}{a character string specifying whether to make the comparison as
lower case, upper case, or any of the two. it defaults to \code{any}.}
\item{dbObj}{any DBI object (e.g., \code{DBIDriver}).}
\item{\dots}{any other argument are passed to the driver implementation.}
}
\value{
\code{make.db.names} returns a character vector of legal SQL
identifiers corresponding to its \code{snames} argument.
\code{SQLKeywords} returns a character vector of all known keywords for the
database-engine associated with \code{dbObj}.
\code{isSQLKeyword} returns a logical vector parallel to \code{name}.
}
\description{
These methods are DEPRECATED. Please use \code{\link[=dbQuoteIdentifier]{dbQuoteIdentifier()}}
(or possibly \code{\link[=dbQuoteString]{dbQuoteString()}}) instead.
}
\details{
The algorithm in \code{make.db.names} first invokes \code{make.names} and
then replaces each occurrence of a dot \code{.} by an underscore \verb{_}. If
\code{allow.keywords} is \code{FALSE} and identifiers collide with SQL
keywords, a small integer is appended to the identifier in the form of
\code{"_n"}.
The set of SQL keywords is stored in the character vector
\code{.SQL92Keywords} and reflects the SQL ANSI/ISO standard as documented
in "X/Open SQL and RDA", 1994, ISBN 1-872630-68-8. Users can easily
override or update this vector.
}
\section{Bugs}{
The current mapping is not guaranteed to be fully reversible: some SQL
identifiers that get mapped into R identifiers with \code{make.names} and
then back to SQL with \code{\link[=make.db.names]{make.db.names()}} will not be equal to the
original SQL identifiers (e.g., compound SQL identifiers of the form
\code{username.tablename} will loose the dot ``.'').
}
\references{
The set of SQL keywords is stored in the character vector
\code{.SQL92Keywords} and reflects the SQL ANSI/ISO standard as documented
in "X/Open SQL and RDA", 1994, ISBN 1-872630-68-8. Users can easily
override or update this vector.
}
\keyword{internal}
|
