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Properties available in the class Consider the following properties: Class Definition: file (vsam,noattr) of record firstname is string(10) lastname is string(30) department is string(20) salary is real(8:2) end Selection Criteria: (department = 'SALES') and (salary > 50000.00) Key Field: department With this Selection Criteria, AionDS first selects all records from the file where the department field is sales. After retrieving these records, AionDS applies the remaining criteria (for example, consider only those records where the salary field exceeds 50000.00). Alternatively, consider the following Selection Criteria property: (department > 'SALES') and (salary > 50000.00) AionDS selects and retrieves all records whose department field is greater than sales (a KSDS stores records in key-sequenced order). AionDS applies the remaining criteria to these retrieved records. The use of the Selection Criteria property on a KSDS file is as follows: ■ If you do not specify a key field in the Key Fields or Alternate Key Field properties, AionDS applies the Selection Criteria to all records in the file. Working with External Databases 7-35