Connection String to MySQL Temporary Table in Java

Question

I am trying to create a temporary table in memory in order to store some data in it and use it within the application life time..

I am trying to do something as follows:

StringBuilder sb = new StringBuilder();
sb.append("CREATE TEMPORARY TABLE XmlItems ENGINE=MEMORY AS (");
// Continue with columns definitions
sb.append(")");

Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/");
Statement stat = conn.createStatement();
stat.executeUpdate(sb.toString());

But the following exception is being thrown:

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

I'm guessing it has to do something with the connection string..

Any ideas?

Answer 1

You haven't provided schema name in the jdbc connection URL. Try after adding schema name at the end of URL.

jdbc:mysql://localhost:3306/myschema

Answer 2

检查以确保在这种情况下（mysql）该数据库已启动/正在运行，尽管您尚未添加要使用的数据库名称而不是"jdbc:mysql://localhost:3306/" ，但连接String看起来还是不错的使用"jdbc:mysql://localhost:3306/databae_name"

Answer 3

The connection string has to contain a database schema to connect to.

DriverManager.getConnection("jdbc:mysql://localhost:3306/myTestDB");

Also, make sure that MySQL is actually running. "Communications link failure" sounds more like the connection to port 3306 is refused.