oracle View the tablespace where the user is located: http://blog.csdn.net/yitian20000/article/details/6256716
oracle grant Detailed explanation: http://blog.csdn.net/xiayang05/article/details/5861846
The table column in Oracle is changed from VARCHAR2 type to CLOB: http://blog.csdn.net/jssg_tzw/article/details/40829867
Create table test
Test main class
public class testClob {
public static void main(String[] args){
testOracleConnection();
}
public static String ClobToString(CLOB clob) throws SQLException, IOException {
String reString = "";
Reader is = clob.getCharacterStream();// Get the stream
BufferedReader br = new BufferedReader(is);
String s = br.readLine();
StringBuffer sb = new StringBuffer();
// Execute the loop to take out all the strings and pay them to StringBuffer from StringBuffer to STRING
while (s != null) {
sb.append(s);
s = br.readLine();
}
reString = sb.toString();
return reString;
}
public static void testOracleConnection()
{
Connection con = null;// Create a database connection
PreparedStatement preStm = null;// Create a precompiled statement object, generally use this instead of Statement
ResultSet result = null;// Create a result set object
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");// Load Oracle driver
System.out.println("Start trying to connect to the database!");
//Connecting to Oracle database provides two ways, OCI way and thin way,
//OCI method is to communicate with Oracle through the local dynamic connection library,
//The speed and security are better, the thin way is to access Oracle remotely
// 127.0.0.1 is the local address, efss is the default database name of the simplified version of Oracle
String url = "jdbc:oracle:thin:@192.168.126.128:1521:XE";
String user = "donald";//User name, the system default account name
String password = "123456";//The password you set during installation
long startTime = System.currentTimeMillis();
con = DriverManager.getConnection(url, user, password);// Get the connection
con.setAutoCommit(false);
preStm = con.prepareStatement("insert into test values(?,?)");
preStm.setInt (1, 1);
String name = "jamel";
Reader clobReader = new StringReader(name); // Convert text to stream
preStm.setCharacterStream(2, clobReader, name.length());// Replace the ? in the sql statement
preStm.execute();
con.commit ();
preStm = con.prepareStatement("select name from test where id = ?");
preStm.setInt (1, 1);
preStm.execute();
con.commit ();
result = preStm.getResultSet ();
while(result.next()){
CLOB clob = (oracle.sql.CLOB) result.getClob(1);// Get the CLOB field str
// Note: The data cannot be obtained with rs.getString("str"), the return is NULL;
String content = ClobToString(clob);
System.out.println("name:"+ content);
}
long endTime = System.currentTimeMillis();
System.out.println("============time:"+ (endTime-startTime));
System.out.println("============hashCode:"+ con.hashCode());
if(!con.isClosed()){
System.out.println("============Connection succeeded!");
}
}
catch (Exception e)
{
System.out.println("============Connection failed: "+e.getMessage());
e.printStackTrace ();
}
finally
{
try
{
// Close the above objects one by one, because not closing them will affect performance and occupy resources
// Note the order of closing, the last used closes first
if (result != null)
result.close();
if (preStm != null)
preStm.close();
if (con != null)
con.close();
System.out.println("Database connection closed!");
}
catch (Exception e)
{
e.printStackTrace ();
}
}
}
}
Console output:
Start trying to connect to the database!
name:jamel
===========time:191
===========hashCode:28890871
===========Connection succeeded!
Database connection closed! Problem: ORA-00942: The table or view does not exist. If you use the navicat client to create a table, the table name will be quoted by default. For example, when you create a table test, you will actually add quotation marks "test" to the table or create a table with navicat. Add quotation marks to the indication: create table "test" If the quotation marks do not work, check whether it is a problem with the user tablespace: check the user tablespace select username, default_tablespace from user_users; change the user default tablespace: alter user donald default tablespace users; summary: When oracle creates a table, it is best not to use the client, use sqlplus, and run the script to create the table.
