R/sum.td.data.frame.R

In nonsleepr/teradataR: Teradata R Package

sum.td.data.frame <- function(tdf, ...) {
    if (!is.td.data.frame(tdf)) 
        stop("'tdf' is not a td data frame")
    if (!length(names(tdf))) 
        stop("td.data.frame contains no columns")
    obj <- .td.object(attr(tdf, "tableName"), attr(tdf, "database"))
    sumVal <- 0
    exprs <- attr(tdf, "expressions")
    
    wc <- ""
    if (!is.null(attr(tdf, "whereClause"))) 
        wc <- paste(" WHERE ", attr(tdf, "whereClause"))
    
    for (i in 1:length(names(tdf))) {
        if (as.character(i) %in% names(exprs)) 
            query <- gettextf("SELECT SUM(%s) FROM %s %s", .td.gencolumnexpr(tdf[i]), obj, wc) else query <- gettextf("SELECT SUM(\"%s\") FROM %s %s", names(tdf)[i], obj, wc)
        df <- try(tdQuery(query))
        if (is.null(attr(df, "class"))) 
            stop("Only defined on a td data frame with all numeric variables")
        sumVal <- sumVal + as.numeric(df)
    }
    return(sumVal)
}