MyBatis cannot find a data query that returns a null problem _java

MyBatis suddenly cannot find the data, the query returns NULL, but the number of select COUNT (*) from XXX queries is normal.

Preparing:select id,a9004,a9005,a9015 from A90 where a9010 =? ORDER BY ID LIMIT 1
[DEBUG] Org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug (basejdbclogger.java:139): http-bio-8080-exec-7-= > Parameters: Science and Technology Review (String)
[DEBUG] Org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug (basejdbclogger.java:139): http-bio-8080-exec-7-<= = total:0

But the SQL:

SELECT id,a9004,a9005,a9015 from A90 where a9010 = ' tech Review ' ORDER by ID LIMIT 1

The direct execution in the Mysql.exe, but has the result.

Later found to be garbled problem, on the database connection to specify the character encoding on the line:

? Autoreconnect=true&useunicode=true&characterencoding=utf8

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