[R] Help with read.csv.sql()

[Gabor Grothendieck]

Probably simplest to assign the names afterwards as others have
suggested but it could be done like this:

  library(sqldf)
  write.csv(BOD, "BOD.csv", quote = FALSE, row.names = FALSE)  # test data

  read.csv.sql("BOD.csv", "select Time as Time2, demand as demand2 from file")

giving the column names Time2 and demand2 rather than the original column names.

    Time2 demand2
  1     1     8.3
  2     2    10.3
  3     3    19.0
  4     4    16.0
  5     5    15.6
  6     7    19.8

On Fri, Jul 17, 2020 at 9:28 PM H <agents using meddatainc.com> wrote:
>
> I have created a dataframe with columns that are characters, integers and numeric and with column names assigned by me. I am using read.csv.sql() to read portions of a number of large csv files into this dataframe, each csv file having a header row with columb names.
>
> The problem I am having is that the csv files have header rows with column names that are slightly different from the column names I have assigned in the dataframe and it seems that when I read the csv data into the dataframe, the column names from the csv file replace the column names I chose when creating the dataframe.
>
> I have been unable to figure out if it is possible to assign column names of my choosing in the read.csv.sql() function? I have tried various variations but none seem to work. I tried colClasses = c(....) but that did not work, I tried field.types = c(...) but could not get that to work either.
>
> It seems that the above should be feasible but I am missing something? Does anyone know?
>
> A secondary issue is that the csv files have a column with a date in mm/dd/yyyy format that I would like to make into a Date type column in my dataframe. Again, I have been unable to find a way - if at all possible - to force a conversion into a Date format when importing into the dataframe. The best I have so far is to import is a character column and then use as.Date() to later force the conversion of the dataframe column.
>
> Is it possible to do this when importing using read.csv.sql()?
>
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