Summary

Important Observations

• Notice that the field level validation rules you created in exercise REP003 - Validation Rules are enforced when you maintain the tables.  Field level validations are enforced in every table in which the field is used. However, remember most validation rules should be defined at table level.

• Key sequence is used to define the order of the keys in the table. The physical sequence of fields and the key sequence are independent.

• Access to tables is handled by the Object Access Modules (OAM). Every table used by a LANSA application has an OAM which contains the repository features of the table and its fields. The OAM is executed whenever the table is accessed by a program.

• When you make a change to a field used in a table or to the table definition itself, you need to recompile the table. You do not need to recompile your programs unless the change affects the visual display.

Tips and Techniques

• Use the multi-add fields feature as a faster way to add fields to a table. You can include fields that do not exist in the repository and these fields will be created when you exit the multi-add window.

• Database attributes become more important if you are deploying databases to other platforms. Refer to the online help for each database attribute before using it.

What I Should Know

• How to define a table in the LANSA repository.

• How to add fields to a table definition.

• How to specify table keys.

• How to compile a table to make it operational.

• Some of the attributes that can be specified for database tables.