看了下mysql-connector-5.1.40版本中，如果设置failoverReadOnly=true (即默认值，参考链接)，当mysql连接failover时，会根据jdbc连接串将当前连接的readOnly值设置为true (第8行代码)
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private synchronized void switchCurrentConnectionTo(int hostIndex, MySQLConnection connection) throws SQLException { invalidateCurrentConnection(); boolean readOnly; if (isPrimaryHostIndex(hostIndex)) { readOnly = this.explicitlyReadOnly == null ? false : this.explicitlyReadOnly; } else if (this.failoverReadOnly) { readOnly = true; } else if (this.explicitlyReadOnly != null) { readOnly = this.explicitlyReadOnly; } else if (this.currentConnection != null) { readOnly = this.currentConnection.isReadOnly(); } else { readOnly = false; } syncSessionState(this.currentConnection, connection, readOnly); this.currentConnection = connection; this.currentHostIndex = hostIndex;} |
当执行update操作时，如果检测到readonly，就会跑出createSQLException （第8-9行代码）
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protected int executeUpdate(byte[][] batchedParameterStrings, InputStream[] batchedParameterStreams, boolean[] batchedIsStream, int[] batchedStreamLengths, boolean[] batchedIsNull, boolean isReallyBatch) throws SQLException { synchronized (checkClosed().getConnectionMutex()) { MySQLConnection locallyScopedConn = this.connection; if (locallyScopedConn.isReadOnly()) { throw SQLError.createSQLException(Messages.getString("PreparedStatement.34") + Messages.getString("PreparedStatement.35"), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor()); } .... }} |
上述报错信息是PreparedStatement.34和PreparedStatement.35，查mysql connector的LocalizedErrorMessages.properties
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PreparedStatement.34=Connection is read-only.PreparedStatement.35=Queries leading to data modification are not allowed |
报错信息一致。
因此， 如果是使用的主备mysql，需要手动切换master和slave，如果使用的是多主的mysql(例如，phxsql)，需要设置failoverReadOnly=false