R/dbpf_fields.R

In geocryology/PermafrostDB: PermafrostDB

# =============================================================================
#'
#' @title Return table of fields for all tables
#'
#' @description Basic information on permafrost database @ Carleton University
#'
#' @details These simple functions return all data as data frames. When
#'          making a query many times, optimise the SQL statement to only
#'          request the data you actually need.
#' 
#' @param con Database connection object, as returned by \code{\link{dbpf_con}}
#' 
#' @param tables Character string or vector of table name(s). If empty, fields
#'              for all tables are returned. Default is tables="".
#'
#' @return List of all fields for all tables in DB
#'
#' @export
#' @examples
#' \dontrun{
#' con <- dbpf_con()
#' fds_o <- dbpf_fields(tables = "observations")
#' }
#' @author Stephan Gruber <stephan.gruber@@carleton.ca>
# =============================================================================
dbpf_fields <- function(con, tables = "") {

  if (missing(con)){
    con <- dbpf_con()
  }

    if (tables[1] == "") {
    	tables <- dbpf_tables(con)
    }
    fields <- NULL
    for (t in 1:length(tables)) {
    	fields <- rbind(fields, dbpf_table_columns(con, tables[t]))
    }
    return(fields)
}