java如何访问Oracle的long类型?

时间：2022-09-15 18:30:05

我现在想用一个字段来存长字符串（在于4000，varchar2不能满足），想到用LONG，但是用JDBC连的时报SQL不正确，请高人指点，相当紧急！！！！

 

Do a search with Google... e.g.
Sample demonstrating the usage of LONG type
http://www.oracle.com/technology/sample_code/tech/java/sqlj_jdbc/files/basic/LongSample/Readme.html


  // Populate the ResultSet
  while(resultSet.next()) {
    InputStream insurancedata; // Holds the LONG data
    StringBuffer dataBuffer = new StringBuffer();

    /* Obtain the LONG data into a byte array. LONG data can be accessed in 
    two ways: 1) By retrieving all the data in one shot (getBytes method)
    2) By using streams. The LONG data is made available to the program
    as an Ascii or Unicode stream, and the data can be retrieved chunk by
    chunk, which is more eficient in terms of memory usage        
    In this sample we illustrate retrieval using streams */
    insurancedata = resultSet.getAsciiStream(1);
    while((chunk = insurancedata.read()) != -1) {
      dataBuffer.append((char)chunk);
    }

 

 

 

Code for inserting Long Data 

public void insertData(String code, String name, String partner, 
                       String textfile) throws Exception {

  // Create a File to read data from the specified text file (textfile)
File file = 
    new File(getClass().getClassLoader().getResource(textfile).getFile());

  // Prepare the statement for inserting a row into the OTN_AIRLINES_LONG
PreparedStatement pstmt = connection.prepareStatement(" INSERT INTO "+
                          "otn_airlines_long( code, name, partner,"+
                          "airline_insurance_data) VALUES(?, ?, ?, ?)");

    // Bind the parameter values for the above statement
    pstmt.setString(1, code); 
    pstmt.setString(2, name); 
    pstmt.setString(3, partner);

    // Bind the AIRLINE_INSURANCE_DATA column to an input Ascii stream that
    // returns the Ascii data to be inserted into the LONGRAW column
    pstmt.setCharacterStream(4, new FileReader(file), (int)file.length());

    // Execute the statement
    pstmt.execute();
  }
}
................
................

Code for retrieving Long Data 

public void displayLongData(String code) {
........
........
  // Create a PreparedStatement object to execute the QUERY
PreparedStatement pst = 
    connection.prepareStatement("SELECT airline_insurance_data"+
                        " FROM otn_airlines_long WHERE code = ?");

  // Bind the airline code to the query
  pst.setString(1, code);
    gui.putStatus("Reading Long Column from the DB, Please wait...");

  // Excute the Query
  ResultSet resultSet = pst.executeQuery();

  // Populate the ResultSet
while(resultSet.next()) {
    InputStream insurancedata; // Holds the LONG data
    StringBuffer dataBuffer = new StringBuffer();
        
/* Obtain the LONG data into a byte array. LONG data can be accessed in 
    two ways: 1) By retrieving all the data in one shot (getBytes method)
    2) By using streams. The LONG data is made available to the program
    as an Ascii or Unicode stream, and the data can be retrieved chunk by
    chunk, which is more eficient in terms of memory usage        
    In this sample we illustrate retrieval using streams */
insurancedata = resultSet.getAsciiStream(1);
    while((chunk = insurancedata.read()) != -1) {
      dataBuffer.append((char)chunk);
    }
................
................

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