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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/sql-expr.R
\name{sql_expr}
\alias{sql_expr}
\alias{sql_call2}
\title{Generate SQL from R expressions}
\usage{
sql_expr(x, con = sql_current_con())
sql_call2(.fn, ..., con = sql_current_con())
}
\arguments{
\item{x}{A quasiquoted expression}
\item{con}{Connection to use for escaping. Will be set automatically when
called from a function translation.}
\item{.fn}{Function name (as string, call, or symbol)}
\item{...}{Arguments to function}
}
\description{
Low-level building block for generating SQL from R expressions.
Strings are escaped; names become bare SQL identifiers. User infix
functions have \verb{\%} stripped.
}
\details{
Using \code{sql_expr()} in package will require use of \code{\link[=globalVariables]{globalVariables()}}
to avoid \verb{R CMD check} NOTES. This is a small amount of additional pain,
which I think is worthwhile because it leads to more readable translation
code.
}
\examples{
con <- simulate_dbi() # not necessary when writing translations
sql_expr(f(x + 1), con = con)
sql_expr(f("x", "y"), con = con)
sql_expr(f(x, y), con = con)
x <- ident("x")
sql_expr(f(!!x, y), con = con)
sql_expr(cast("x" \%as\% DECIMAL), con = con)
sql_expr(round(x) \%::\% numeric, con = con)
sql_call2("+", quote(x), 1, con = con)
sql_call2("+", "x", 1, con = con)
}
\keyword{internal}
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