Cannot read unicode from "PostgreSQL Unicode(x64)"

[david-cortes]

Steps to reproduce:

• Connect to some postgre database in windows using connection string with driver PostgreSQL Unicode(x64). Optionally, specify the encoding to be UTF-8 in the dbConnect argument. Example:

con <- DBI::dbConnect(odbc::odbc(),
    .connection_string = "Driver={PostgreSQL Unicode(x64)`};Server=server;Port=5432;Database=db;
Uid=user;Pwd=pwd;",
    encoding = "UTF-8")

• Retrieve data from some table (not from some self-sufficient statement like select 'str') through dbGetQuery (from any package, e.g. DBI, RPostgreSQL, RPostgres). Example:

df <- DBI::dbGetQuery(con, "select problem_col from some_table limit 10")

• Inspect said data in R.

Expected results: output data.frame from dbGetQuery should have the data as it is in the table, encoded in UTF-8.

Actual results: all the non-ascii characters get replaced with question marks, and the encoding from R's Encoding(char_vector) is "unknown". Forcing it to some other encoding does not make a difference.

The problem is not present in linux with driver PostgreSQL UNICODE (which is not accepted under windows).