


How to Fetch Non-ASCII Characters from MySQL in R: Why do I see \'?????\' instead of UTF-8 text?
UTF-8 Enigma: Fetching Non-ASCII Characters from MySQL in R
In the realm of data manipulation, extracting UTF-8 text from MySQL databases can sometimes be an enigmatic task. While all characters in UTF-8 should seamlessly render within R, it's not always so straightforward when accessing data via R.
The Mystery: "?????" for Non-ASCII Characters
When retrieving UTF-8 text from MySQL into R, the disheartening "?????" can replace all non-ASCII characters. This peculiar phenomenon has left many R enthusiasts scratching their heads.
Culprit Exposed: Character Set Mismatches
The key to solving this puzzle lies in identifying the culprit: mismatched character sets. The connection session between R and MySQL is typically set to use latin1 as the character set, which is unable to display UTF-8 characters.
Solution Unveiled: Enforcing UTF-8
To rectify the situation, there are two elegant solutions:
- RMySQL: Execute the "SET NAMES utf8" query after establishing the connection. This explicitly sets the character set to UTF-8, allowing proper rendering of characters.
- RODBC: Specify "CharSet=utf8" within the DSN string while connecting. This ensures that the connection uses UTF-8 right from the start, eliminating the need for manual character set manipulation later.
The above is the detailed content of How to Fetch Non-ASCII Characters from MySQL in R: Why do I see \'?????\' instead of UTF-8 text?. For more information, please follow other related articles on the PHP Chinese website!

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