


Why are My UTF-8 Characters Garbled When Transferring Data Between MySQL Databases Using Java?
Reading/Writing UTF-8 Data in MySQL from Java Using JDBC Connector 5.1: Troubleshooting Connection Issues
When working with MySQL and Java using JDBC connector 5.1, it's common to encounter encoding issues when dealing with UTF-8 data. Let's address a specific scenario where characters appear garbled during data transfer.
The issue arises when reading UTF-8 data from a MySQL database and writing/updating it to another MySQL database using a Java timer service. Additionally, when viewing the loaded data through a web application, the characters still appear incorrect despite the correct HTTP headers.
To diagnose the problem, it's important to examine the database settings. The following settings indicate that the databases are using UTF-8 encoding:
character_set_client-->utf8 character_set_connection-->utf8 character_set_database-->utf8 character_set_results-->utf8
However, the following setting suggests a potential issue:
character_set_server-->latin1
Changing character_set_server is not feasible, but another approach can be taken. To correctly read UTF-8 data from MySQL using JDBC connector, ensure that the connection string includes the following parameters:
useUnicode=true&characterEncoding=UTF-8
This configuration ensures that the JDBC driver uses the appropriate encoding for communication with the database. By incorporating this parameter into the connection string, you can resolve the data corruption issue.
While the connection parameters address the reading aspect, writing UTF-8 data to the second database might still present challenges. To solve this, verify that the web application is sending the data in UTF-8 encoding. Additionally, ensure that the second database has the correct character encoding settings (e.g., character_set_database=utf8) to accept and store the data correctly.
The above is the detailed content of Why are My UTF-8 Characters Garbled When Transferring Data Between MySQL Databases Using Java?. For more information, please follow other related articles on the PHP Chinese website!

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