Fetching UTF-8 text from MySQL in R returns "????"
Solution 1
Thanks to @chooban I found out the connection session was using latin1 instead of utf8. Here are two solutions I found:
- For RMySQL, after connecting run the query
SET NAMES utf8
to change the connection character set. - For RODBC, connect using
CharSet=utf8
in the DSN string. I was not able to runSET NAMES
via ODBC.
This question pointed me in the right direction.
Solution 2
This worked for me. Here is a full example:
con = dbConnect(drv = MySQL(), user = user, password = password,
dbname = dbname, host=host)
dbSendQuery(con, "SET NAMES utf8mb4;")
dbSendQuery(con, "SET CHARACTER SET utf8mb4;")
dbSendQuery(con, "SET character_set_connection=utf8mb4;")
dbGetQuery(con, "SELECT * FROM WHATEVER")
Solution 3
Here's something to try at least. After you've connected, run "SHOW VARIABLES LIKE 'character_set_%'" and print out the results. If nothing else it's a useful check to see if the character set options you've specified have taken.
Daniel Dickison
I love Lisp, finding Swift pretty great, and I'd probably get hooked on Rust if I found some time to get to know it. Also: I don't hate JavaScript.
Updated on June 03, 2022Comments
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Daniel Dickison almost 2 years
I'm stuck trying to fetch UTF-8 text in a MySQL database from R. I'm running R on OS X (tried both via the GUI and command line), where the default locale is en_US.UTF-8, and no matter what I try, the query result shows "?" for all non-ASCII characters.
I've tried setting
options(encoding='UTF-8')
,DBMSencoding='UTF-8'
when connecting via ODBC, settingEncoding(res$str) <- 'UTF-8'
after fetching the results, as well as 'utf8' variants of each of those, all to no avail. Running the query from the command line mysql client shows the results correctly.I'm totally stumped. Any ideas why it's not working, or other things I should try?
Here's a fairly minimal test case:
$ mysql -u root mysql> CREATE DATABASE test; mysql> USE test; mysql> CREATE TABLE test (str VARCHAR(10)) ENGINE=InnoDB DEFAULT CHARSET=utf8; Query OK, 0 rows affected (0.02 sec) mysql> INSERT INTO test (str) VALUES ('こんにちは'); Query OK, 1 row affected (0.00 sec) mysql> select * from test; +-----------------+ | str | +-----------------+ | こんにちは | +-----------------+ 1 row in set (0.00 sec)
Querying the table in R using both RODBC and RMySQL shows "?????" for the str column:
> con <- odbcDriverConnect('DRIVER=mysql;user=root', DBMSencoding='UTF-8') > sqlQuery(con, 'SELECT * FROM rtest.test') str 1 ????? > library(RMySQL) Loading required package: DBI > con <- dbConnect(MySQL(), user='root') > dbGetQuery(con, 'SELECT * FROM rtest.test') str 1 ?????
For completeness, here's my sessionInfo:
> sessionInfo() R version 2.15.1 (2012-06-22) Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit) locale: [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] RMySQL_0.9-3 DBI_0.2-5 RODBC_1.3-6