ER/Studio - Embarcadero Technologies Product Documentation

USING ER/STUDIO > DEVELOPING THE PHYSICAL MODEL
Materialized View Characteristics Fast Refresh Method is Supported When
the Materialized View has:
No subqueries, inline views, or set functions like UNION or MINUS X X X
COUNT(*) must be present X
No MIN and MAX allowed X
If outer joins, then unique constraints must exist on the join columns of
the inner join table
Materialized view logs must exist and contain all columns referenced
in the materialized view and have been created with the LOG NEW
VALUES clause
Materialized view logs must exist with rowids of all the detail tables X
Non-aggregate expression in SELECT and GROUP BY must be
straight columns
Creating and Editing Node Groups
A node group is a named set of one or more database partitions. A node group can have 2 to 32 nodes defined for it.
The number of nodes that is defined for the node group determines the number of systems across which the database
file is created.
You may need to create a node group when you want the database files to be visible across a set of System i
models in a load sharing and balancing environment. Nodgroups enable workload to be processed in parallel across a
partitioned database for large tables, while smaller tables can be stored on one partition or on a small number of
partitions if desired.
The following database platforms support node groups:
• IBM DB2 for LUW 5.x, 6.x, 7.x, 8.x, 9.x
NOTE: The DB2 Nodegroup Wizard and DB2 Nodegroup Editor share the same options, except for
Attachment Bindings options which are defined in the editor only.
Create a Node Group
1 In the Data Model Explorer, expand the physical Main Model, right-click the Node Groups node, and then click
New Nodegroup.
2 Complete the Node Groups Wizard and then click Finish to create the node group.
TIP: Once you have created the auxiliary table, you can edit it by right-clicking the node group you want
to change, and then clicking Edit Node Group.
The following describe options that require additional explanation.
Only Joins Joins and
Aggregates
DML to detail table X X
Direct path data load X X X
ON COMMIT X X
ON DEMAND X X X
EMBARCADERO TECHNOLOGIES > ER/STUDIO® 8.0.3 USER GUIDE 199
X
Am Aggregate
on a Single
Table
X
X