Building integrity constraints right into the database is the surest way to make sure your data stays in good shape. This chapter describes the facilities in Adaptive Server Anywhere for ensuring that the data in your database is valid and reliable.
You can enforce several types of integrity constraints. For example, you can ensure individual entries are correct by imposing constraints and CHECK constraints on tables and columns. Setting column properties by choosing an appropriate data type or setting special default values assists this task.
The SQL statements in this chapter use the CREATE TABLE and ALTER TABLE statements, basic forms of which were introduced in Working with Database Objects.
Data integrity overview
Using column defaults
Using table and column constraints
Using domains
Enforcing entity and referential integrity
Integrity rules in the system tables