Hi, Dmytro
Thanks for the reply, I am using trident topology, here is my static class,
but I think this is incorrect since trident process data in batch, but
following code process single row.
public static class WriteDB extends BaseFunction {
private Connection conn = null ;
PreparedStatement ps = null;
@Override
public final void execute(final TridentTuple tuple, final
TridentCollector collector) {
int user = tuple.getInteger(0);
String value = tuple.getString(1);
final StringBuilder queryBuilder = new StringBuilder()
.append("INSERT INTO test.state(userid,
event) VALUES(")
.append(user)
.append(", '")
.append(value)
.append("')");
System.out.println(queryBuilder.toString());
try {
ps =
conn.prepareStatement(queryBuilder.toString()) ;
ps.execute();
collector.emit(new
Values(tuple.getStringByField("event")));
}
catch (SQLException ex) {
System.err.println("Caught IOException: " +
ex.getMessage());
} finally {
if (ps != null) {
try {
ps.close();
} catch
(SQLException ex) {
}
}
}
}
}
Any idea?
thanks
On Fri, Dec 5, 2014 at 2:35 PM, Dima Dragan <[email protected]>
wrote:
> Hi,
>
> I think better approach is creating static class with thread-safe
> singleton initialization of connection pool (for example, I use HikariCP
> for SQL db and JedisPool for Redis) and provide public access for getting
> connection from it to bolt. Init pool in prepare method, take
> connection,execute smth, give it back in execute method.
>
> So every worker will get it's own pool which is shared between bolts.
>
> Best regards,
> Dmytro Dragan
> On Dec 5, 2014 11:57 PM, "Sa Li" <[email protected]> wrote:
>
>> Hi, all
>>
>> Right now I am able to write tuples into a file, and use copy command to
>> load into database, but this is obviously not a perfect solution, increase
>> complexity and overheads. Any idea to make it simpler?
>>
>>
>> thanks
>>
>>
>> Alec
>>
>
