对于ubuntu 16.04
第1步:
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 2930ADAE8CAF5059EE73BB4B58712A2291FA4AD5
第2步:
echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/3.6 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.6.list
第3步:
sudo apt-get update
第4步:
sudo apt-get install -y mongodb-org
第5步:
sudo service mongod start
当我开始mongodb得到一个错误
"Failed to start mongod.service: Unit mongod.service not found." please help me to solve this.
我在安装C编译器本身时面临以下错误(gcc gnu).
configure: error: in `/home/gcc-5.3.0':
configure: error: no acceptable C compiler found in $PATH
注意到我已经尝试了这个问题中列出的解决方案但没有成功.
操作系统:RHEL6和CentOS
通过以下代码发送到Oracle DB的查询，并且应该以以下形式返回查询结果JSON：
Connection conn ;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
String url = "jdbc:oracle:thin:@localhost:1521:dbname";
conn = DriverManager.getConnection(url,"username","pwd");
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * FROM table4 where ID = '5'");
while (rs.next()) {
String s = rs.getString("*");
response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");
response.getWriter().write(s);
}
conn.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
但是，的值String s始终为null。