使用JDBC URL连接到数据库

Question

My requirement is to check can we connect to a database with no schema defined through a java program and create a database. this works fine

Connection  connection =
           DriverManager.getConnection("jdbc:db2://wcspocca-db.cloudapp.net:50001/db2inst1","vmadmin","password@123;");

database: db2 schema: db2inst1

but

Connection  connection =
           DriverManager.getConnection("jdbc:db2://wcspocca-db.cloudapp.net:50001/","vmadmin","password@123;");

fails WHY?

com.ibm.db2.jcc.am.mo: [jcc][10165][10045][4.7.85] Invalid database URL syntax: jdbc:db2://wcspocca-db.cloudapp.net:50001/. ERRORCODE=-4461, SQLSTATE=42815

Answer 1

DriverManager.getConnection("jdbc:db2://wcspocca-db.cloudapp.net:50001/!!DBNAME!!","vmadmin","password@123;");

Answer 2

Because in the second example the database is not specified. You can find the requirements in the DB2 JDBC documentation :

>>-+-jdbc:db2:------+--//--server--+---------+--/--database----->
   +-jdbc:db2j:net:-+              '-:--port-'
   '-jdbc:ids:------'

>--+---------------------------+-------------------------------\><
   '-:--| connection-options |-'

The database parameter is not optional.

Answer 3

How I usually connect to a database using jave is like the following: Spacing it out to allow you to read the text below

//Wide Scope Variables
static Connection conn = null; //right now this connection is off
static String dbURL = "database url"; //I use SQL developer and your able to grab the connection url there

static String user = "This can be empty and ask user for input of hard code the user name";

static String pass = "same as above";

In the method where you want to check the driver and connection I usually do it like this

//Register the Driver
    try
    {
        Class.forName("oracle.jdbc.driver.OracleDriver");   
    }
    catch(ClassNotFoundException e)
    {
        System.err.println(e.getMessage());
    }

    //Set up connection
    try
    {
        conn = DriverManager.getConnection(dbURL,user,password);
        conn.clearWarnings();
        stmt = conn.createStatement();
    }
    catch(SQLException e)
    {
        System.err.println(e.getMessage());
    }

The first try catch code registers the driver to the SQL developer then the second try catch sets up the connection to the database. This helped save me a lot of head aches and I find it the most Direct route when using java.

Answer 4

check the url carefully, after the port number if you do not put database name which you want to connect then how it will connect. Its like you are giving a home address whitout the plot number.