Error 515: Not connected to a Bluetooth device. 原因：经典蓝牙设备未正常连接上，就进行数据收发操作导致的异常，加一个连接状态判断就行。

ORACLE 启动提示 内存不足 OUTOF MEMORY原配置 etc sysctl.conf文件kernel.shmall = 2097152kernel.shmmax = 2147483648kernel.shmmni = 4096kernel.sem = 250 32000 10... 原配置 /etc/sysctl.conf文件 kernel.shmall = 2097152 kernel.shmmax = 2147483648 kernel.shmmni = 4096 kerne...

Plsqldev SQL含中文查无结果设置环境变量：NLS_LANG值为：SIMPLIFIED CHINESE_CHINA.ZHS16GBK设置环境变量：NLS_LANG 值为：SIMPLIFIED CHINESE_CHINA.ZHS16GBKPlsqldev 中文 无结果

常用Sqlmysql：drop table if exists tablename;不能写成drop table tablename if exists tablename;mysql：建立索引SqlCREATE TABLE t...mysql：drop table if exists tablename; 不能写成 drop table tablename if exists tablename; mysql：建立索引Sql CREATE TABLE tablename ( `ID...

Mysql substr和Oracle substr区别Oracle substr(字符串，开始索引、从0起，长度)Mysql substr或substring(字符串，开始索引、从1起，长度)Oracle substr(字符串，开始索引、从0起，长度) Mysql substr或substring(字符串，开始索引、从1起，长度)Mysql Orac...

MongoDB.Driver.MongoConnectionException: Unable to connect to the primary memberMongoDB Driver MongoConnectionException: Unable to connect to the primary member of the replica set: Too many thread MongoDB.Driver.MongoConnectionException: Unable to connect to the primary member of the replica set: ...

C# 操作MongoDb插入、更新、查询Mongo连接字符串形式：mongodb: 127.0.0.1:27017 插入或更新一条记录BsonDocument doc = new BsonDocument();...MongoServer serv...Mongo连接字符串形式：mongodb://127.0.0.1:27017 // 插入或更新一条记录 BsonDocument doc = new Bso...

设置环境变量：NLS_LANG 值为：SIMPLIFIED CHINESE_CHINA.ZHS16GBK

如题。 运行效果：