Direct Load Materialization

Use direct load materialization to materialize data between different kinds of primary and replicate databases.

Direct load materialization differs from other automatic materialization methods:

This automatic materialization method can be used for Adaptive Server, Microsoft SQL Server, Oracle, and DB2 UDB primary databases.
Materialization queues are not used with direct load materialization. Data is loaded directly from a primary table into a replicate table.
Replication is suspended selectively:
- Replication of tables continues for tables that are not being materialized. DML operations on a primary table that is not being materialized are replicated into the replicate table as the DSI receives them.
- DML operations on a primary table that is being materialized are stored in a catch-up queue and applied to the replicate table after the initial materialization phase.
  Note: When DML operations in a catch-up queue are applied to the replicate table, each insert operation is converted into a delete followed by an insert. Materialization fails when an update changes the primary key.
Multiple tables can be concurrently materialized with direct load materialization.
When subscription materialization stops due to an error, regular replication of other tables is not suspended.
Multiple threads can be used to load data from one primary table to its corresponding replicate table. You can tune this multi-threaded behavior with max_mat_load_threads.

Direct load materialization can be used to materialize data:

from Adaptive Server to HANA DB
from Microsoft SQL Server to HANA DB
from Oracle to HANA DB
from DB2 UDB to HANA DB

Note: Direct load materialization is not supported for materializing data into an Adaptive Server database.

Direct load materialization is enabled through the direct_load option of the create subscription command. When using direct load materialization, note these restrictions for create subscription:

When the direct_load option is used, no other subscription can be created or defined at the same time for the same replicate table.
The direct_load option is for subscriptions to table replication definitions only and is used with without holdlock. It cannot be used with the without materialization or incrementally options.
The user and password options are used only with direct_load.
You cannot use the direct_load option against a logical or alternate connection. The primary connection in the replication definition and the replicate connection in the subscription must be physical connections.
The maintenance user of the primary database cannot be used in the user and password options to create subscriptions.
You cannot use other automatic materialization methods if the primary database is not Adaptive Server. The only automatic materialization option for Oracle or other databases is direct load materialization.
You cannot drop a subscription with the with purge option if the replicate database is not Adaptive Server.
The direct_load option is available only if the replicate Replication Server site version and route version are 1571100 or later.
You can use row filtering, name mapping, customized function strings and datatype mapping with subscriptions created using the direct_load option.
Replication Server rejects any attempt to create a subscription with the direct_load option if the number of subscriptions being created has reached or exceeded num_concurrent_subs.

Primary Database Considerations

In directly materializing data from a primary database, Replication Server connects to Replication Agent and not directly to the primary database.
You must have Replication Agent version 15.7.1 SP100 or later to materialize data from a non-Adaptive Server primary database using direct load materialization.
When invoking the create subscription command, Replication Server connects to Replication Agent using the Replication Agent administrator login name.