IBM DB2 manual Load utility, 237

Because our tables are empty, we choose the insert mode. In Example 5-15we show the statements to populate our sample database using the IXF files exported in the previous section.

Example 5-15 Import statements used to populate our sample database

import from "dept.ixf" of ixf messages "dept.msg" insert into itso.department; import from "emp.ixf" of ixf messages "emp.msg" insert into itso.employee; import from "staff.ixf" of ixf messages "staff.msg" insert into itso.staff;

Because referential constraints are set during import, tables must be imported in the right order. In our example, there is a foreign key relation from the EMPLOYEE table to the DEPARTMENT table, therefore, we must import the DEPARTMENT table before the EMPLOYEE table.

There are several other options that can be used to control the import utility. For a thorough description, refer to the DB2 Infocenter:

http://publib.boulder.ibm.com/infocenter/db2luw/v9r5/topic/com.ibm.db2.luw.admi

n.dm.doc/doc/c0004573.html4

Load utility

The load utility writes formatted pages directly into the database, which makes it much faster then the import utility. The load utility does not perform referential constraints or table constraint checking. The only validation performed is that the uniqueness of the indexes. Like the import utility, different load modes are

available to control what to do with the existing data. For an initial load, we can choose between insert or replace mode. Because our tables are empty, it makes

no difference which mode is chosen.

After load, the tables with constraints will be in the integrity pending mode and cannot be accessed. You can use the set integrity command to check the constraints and bring the table back to the accessible mode.

In our sample database we have a referential constraint defined between the

EMPLOYEE table to the DEPARTMENT table. After loading, the EMPLOYEE table will be in the integrity pending mode because the foreign key relation has not

been checked. Furthermore, the summary table also has to be checked. Example 5-16shows the load statements and the required check statements to populate our database and make the tables accessible.

Example 5-16 The load and integrity check statements for our sample database

load from "emp.ixf" of ixf messages "emp.msg" insert into itso.employee copy no indexing mode autoselect;

load from "dept.ixf" OF ixf messages "dept.msg" insert into itso.department copy no indexing mode autoselect;

Chapter 5. Deploying pre-configured databases 237