Comparison of insert, copy, and insert append operations in oracle

Comparison of insert, copy and insert append operations in oracle is still due to database migration. The execution speed of insert, copy and insert append is tested. Environment: migrate oracle9i to oracle11g, linux system. The table has been created and only data can be inserted. You cannot use create... select or copy... create. 1. Create a dblink for insert and insert append. 2. log on to the 11g database. Set timing on3. create a view to view redo size create redo_size asselect value www.2cto.com from v $ mystat, v $ statname where v $ mystat. statistic # = v $ statname. statistic # and v $ statname. name = 'redo size'; 4. insert into dblink_test_tab select * from tran_rec_03 @ dblink_test; insert/* + APPEND */into dblink_test_tab select * from tran_rec_03 @ dblink_test; copy from ispay/ispay @ crmtest insert dblink_test_tab using select * from tran_rec_03; execute select * from redo_size; 5 before and after executing all the preceding statements. the result is as follows:
When redo_size is used, insert 177821968 4 '25 "insert append 3590412 3 '15" copy 124438620 4 '20 "data volume: 495665 www.2cto.com. Conclusion: insert takes the most time, and redo takes the most.
Insert append requires the shortest time and the minimum redo volume.
Copy does not require dblink.