Question

我正在尽我所能让JDBC工作，现在唯一让我烦恼的是这个例外，我不知道：

com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '????????????????' at line 1
    com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1049)
    com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3593)
    com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3525)
    com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1986)
    com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2140)
    com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2620)
    com.mysql.jdbc.ConnectionImpl.configureClientCharacterSet(ConnectionImpl.java:1890)
    com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3523)
    com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2386)
    com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2163)
    com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:794)
    com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:374)
    com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
    java.sql.DriverManager.getConnection(libgcj.so.10)
    java.sql.DriverManager.getConnection(libgcj.so.10)

我正在使用它连接......

Class.forName("com.mysql.jdbc.Driver");
DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql", "username", "password");

非常感谢！

Answer 1

这些是相关部分：

com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL
syntax; check the manual that corresponds to your MySQL server version for the 
right syntax to use near '????????????????' at line 1
    ...
    com.mysql.jdbc.ConnectionImpl.configureClientCharacterSet(ConnectionImpl.java:1890)
    ...
    java.sql.DriverManager.getConnection(libgcj.so.10)

这些问号表示在查询期间配置客户端字符集时出现严重的字符编码问题。

首次尝试时，打开my.cnf文件并确保存在以下两个条目：

character_set_server=utf8
collation_server=utf8_general_ci

第二次尝试时，请将OpenJDK或Oracle (Sun) JDK替换为更健壮的GCJ。众所周知，GCJ有其奇特之处。

JDBC的难倒SQL异常

1 个答案: