Handling large records in a Java EE application

Question

There is a table phonenumbers with two columns: id, and number. There are about half a million entries in the table. Data

Answer 1

If using Mysql 5.1+, I would simply use the proprietary syntax to dump the file somewhere and stream it in a Servlet response.

SELECT a,b,a+b INTO OUTFILE '/tmp/result.txt'
  FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
  LINES TERMINATED BY '\n'
  FROM test_table;

http://dev.mysql.com/doc/refman/5.1/en/select.html

For so many records, if you still want to use JDBC, you may try the following:

• fetch the number of records fetch few records( using a query limit ) and write them
• if you reach the number of records in a chunk, you fetch another one until you reach the maximum number of records