How can a database be segmented?
In any way you want, depending on the information held on the database. Age, sex, postcode are basic identifiers but ethnicity, educational qualifications and recency/frequency of spend are all useful in targeting your readership. One profiling programme identifies first names as an indicator of age and/or economic circumstance: Enid, Violet and Mabel have different connotations to Camilla, Tamsin and Fiona.