why is the .con argument even needed in glue::glue_sql?

[von_olaf]

Hello there!

That might be a very simple question, but why is the .con argument needed in the glue_sql functions? I mean, say I am just embedding a subquery into another query, what additional information does the connection bring?

Perhaps I am missing something there? I am using Oracle.

Thanks!

[andresrcs]

I believe that .con argument tells glue_sql what specific sql flavor needs to take to account.

[jimhester]

The type of quoting needed varies by SQL dialect, so the .con argument is needed to determine what to use.

If you are always using the same type of database / connection you can write a simple wrapper function to avoid needing to pass .con, e.g.

library(DBI)
oracle_con <- dbConnect(ROracle::dbDriver("Oracle"), "scott", "tiger")

glue_orc <- function(..., .envir = parent.frame(), .na = DBI::SQL("NULL")) {
  glue::glue_sql(..., .con = oracle_con, .envir = envir, .na = na)
}

[von_olaf]

thanks @jimhester and @andresrcs, that is useful!