Generating Unique Values

USoft allows you to define a table with a primary key column whose values are automatically generated. Each record then gets a unique value. Generation of unique values can take place:

·	By creating a sequence object in the (Oracle or Solid) database.

·	By simulating a sequence object with the TABLE_SEQUENCE_NUMBERS table (on all other RDBMS's).

·	By having the Rules Engine generate the unique numbers.

·	By having an external component generate the unique values. This is covered in related help topic: Generating Unique Values Using a Component.

To use this feature, you must first create a domain with integer value and with the 'Generate Unique Values' check box set to Database. Then create a primary key column using this domain. If you now insert a new record in this table in your application, USoft automatically generates a unique value for this column. To do that, USoft either creates (or simulates) a Sequence Object if the column is a unique key, or the Rules Engine calculates the value if the column is part of a composed key.

NOTE:

Only one sequence object (for Oracle or Solid) or simulated sequence object (for other RDBMS's) can be used per table.