com.mysql.jdbc.exceptions.jdbc4.

问题：
java异常：
com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry ‘oqKQM5LBRj2iwTG6zzGwlgPWuNjE-2019-10-31 14:38:14’ for key ‘openid’

数据库异常：
[Err] 1062 - Duplicate entry ‘oqKQM5LBRj2iwTG6zzGwlgPWuNjE-2019-11-01 09:49:59’ for key ‘openid’

原因：
关键字’openid’的重复条目’ oqkqm5lbrj2iwtg6zzlgpwunjj -2019-10-31 14:38:14’
数据库的表里设置了同一openId不允许出现重复startTime的唯一键，下面这行sql

UNIQUE KEY `openid` (`openid`,`startTime`) USING BTREE

解决办法：
推荐的解决办法是：按照表的设计，两个字段添加不重复的字段值
不推荐的解决办法：去修改表的设计

详细问题：
com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Duplicate entry ‘oqKQM5LBRj2iwTG6zzGwlgPWuNjE-2019-10-31 14:38:14’ for key ‘openid’
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:407)
at com.mysql.jdbc.Util.getInstance(Util.java:382)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1039)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3603)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3535)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1989)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2150)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2626)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2119)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2415)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2333)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2318)