R/filter_rbr.R

In jkennel/rbr: Assists with handling rbr (.rsk files) in R

#===============================================================================
#' @title Obtain data from rbr sqlite3 database
#'
#' @description Import sqlite data to R
#'
#' @author Jonathan Kennel \email{jkennel@uoguelph.ca}
#'
#' @param db_name the path to the rbr database ( rsk )
#' @param start_date character date
#' @param end_date character date
#' @param use_rbr_tz boolean use time zone information from the rbr file?
#'
#' @return data.table of results
#' @import data.table
#' @importFrom dplyr '%>%'
#' @importFrom dplyr collect
#' @importFrom dplyr select
#' @importFrom dplyr sql
#' @importFrom dplyr tbl
#' @importFrom DBI dbConnect
#' @importFrom DBI dbListTables
#' @importFrom RSQLite SQLite
#' @importFrom measurements conv_unit
#' @importFrom stats na.omit
#'
#' @export
#===============================================================================
filter_rbr <- function(db_name, start_date, end_date, use_rbr_tz = TRUE) {

  # convert text to POSIXct
  start_date <- anytime::anytime(start_date, asUTC = TRUE)
  end_date <- anytime::anytime(end_date, asUTC = TRUE)

  sql_text <- paste0("SELECT tstamp/1000.0 as datetime, * FROM data WHERE tstamp >= ",
                     as.numeric(start_date) * 1000.0, " AND tstamp <= ",
                     as.numeric(end_date) * 1000.0)

  return(read_rbr_db(db_name, sql_text, use_rbr_tz))

}