antonio saginario

Greenhorn
+ Follow
since Nov 18, 2001
Merit badge: grant badges
For More
Cows and Likes
Cows
Total received
In last 30 days
0
Forums and Threads

Recent posts by antonio saginario

Hy,
I'm working on websphere advanced server edition 4.0 and i'm defined and configured a Custom service.
the service consists in a frame with two push-buttons (has used awt). The problem is that the service leaves correctly but does not visualize the window.
Please help me
Antonio
22 years ago
hi,
I have a serious problem with very very large Recordset data (say 25 milion record).
I have noticed that store in memory (using Vector p.e.)this kind of data is more expensive.
Another solution is to take open a scrollable ResultSet (JDBC 2.0) but Oracle Documentation say that JDBC cache on memory all the row.
My application consists of several servlets which on user request produce dynamic SQL queries. The results are shown to the user on HTML pages by a pagination in the memory.
Help me to find a good solution for this problem
Best Wishes.
23 years ago

Originally posted by Ernest Lee:
Please tell us more about the purpose of your application.


Please forgive me for the missing informations. The application consists of several servlets which on user request produce dynamic SQL queries. These queries can
return from 0 to more than 100000 records. The results are shown to the user by a pagination in the memory.
The ResultSet reading, which follows more or less the scheme that I described in the previous mail, produces the application crashing when the two nested cycles are very long. I made a kind of optimization, managing on my best the local objects creation and the Vector presizing, but actually I can't understand if the problem is the memory size or if it depends on other factors as for example the RecordSet reading.
Any suggestion will be pleasant. Thank you.

Best Wishes.

23 years ago
Hi,
When I use
ResultSet rs = stmt.executeQuery("Select * from ..."); I retrieve a ResultSet which contains many records (say 10000). Subsequently I loop on the ResultSet and load a Vector with data extract from ResultSet. In particular i nested two loop like in example below:
Vector result = new Vector();
ResultSetMetaData rsm = rs.getMetaData();
while(rs.next){
result.add(rs.getString(1));
...
for(j=x;j<rsm.getColumnCount();j++){>
if (rsm.getColumnType.equals("CHAR")){
.....
result.add(rs.getString(j));
}
else{
.....
result.add(rs.getBigDecimal(j));
}
}
}
The performance of this loop is very low and in many case the application crash.
My question is, how can I handle these kinds of huge resultsets and how can improve the application performance.
Note:
I have noticed that my DBMS (Oracle 8) execute the query in few millisecond.
Regards,
Antonio S.
23 years ago
Hi,
When I use
ResultSet rs = stmt.executeQuery("Select * from ..."); I retrieve a ResultSet which contains many records (say 10000). Subsequently I loop on the ResultSet and load a Vector with data extract from ResultSet. In particular i nested two loop like in example below:
Vector result = new Vector();
ResultSetMetaData rsm = rs.getMetaData();
while(rs.next){
result.add(rs.getString(1));
...
for(j=x;j<rsm.getColumnCount();j++){>
if (rsm.getColumnType.equals("CHAR")){
.....
result.add(rs.getString(j));
}
else{
.....
result.add(rs.getBigDecimal(j));
}
}
}
The performance of this loop is very low and in many case the application crash.
My question is, how can I handle these kinds of huge resultsets and how can improve the application performance.
Note:
I have noticed that my DBMS (Oracle 8) execute the query in few millisecond.
Regards,
Antonio S.
23 years ago