Oracle database hints for bulk Insert from DBLink

Question

I need to insert around 50 tables that have bulk data in them via DBLink. I generally use the statement

insert into <table_name> 
select * from <table_name>@DBLink

In some cases, it takes too long to insert. What useful database hints can be used in here to speed up the process?

Answer 1

You can use ORACLE's APPEND hint

The APPEND hint tells the optimizer to perform a direct-path insert, which improves the performance of INSERT .. SELECT operations for a number of reasons:

Data is appended to the end of the table, rather than attempting to use existing free space within the table.

Data is written directly to the data files, by-passing the buffer cache.

Referential integrity constraints are not considered. *

No trigger processing is performed. *

Syntax:

INSERT /* + APPEND */ INTO YourTable
SELECT * FROM YourTable@DBLink