Dblink poor performance with varchar(4000) after upgrade 11g

Question

Hi
Since a long time we connected from a 10g database via dblink to another 10g database to copy a simple table with four columns. Tablesize at about 500MB
column1 (varchar(100))
column2/3/4 (varchar(4000)).
After the upgrade of the source database to 11g the dblink performance is poor with the big varchar columns. If I copy (select column1 from ) only column1 then I get the data within minutes. If I want to copy the whole table (select column1, column2, column3, column4 from...) then the performance is poor. It didn't finish within days.
Does anyone know about dblink issues with 11g and big varchar columns?
Thank you very much

Answer 1

Use DBlink to pull data from table(s) using IMPDP:
#1 Create DBlink in the Target database
create database link sourceDB1_DBLINK connect to system identified by password10 using 'SourceDB1';
[update tnsnames.ora appropriately]
#2
select DIRECTORY_PATH from dba_directories where DIRECTORY_NAME=’DATA_PUMP_DIR’;
create DATA_PUMP_DIR directory if not exists
#3
impdp system/pwdxxx SCHEMAS=SCOTT NETWORK_LINK=ORCL10R2 JOB_NAME=scott_import LOGFILE=data_pump_dir:network_imp_scott.log
That's all