DBAS27198 Lecture Notes - Lecture 10: Binary Search Algorithm, Referential Integrity, Unique Key

• School: Sheridan College
• Department: Database Design and Administration
• Course: DBAS27198
• Professor: Burgess

Document Summary

Decision on what model to use should be based on how many records it could potentially hold. Need to understand how often data is accessed, like access frequency per hour, i. e. 8000 times per hour. Need to know how much data and use of the data. Clob=character large object, stores 4gb of a character data field. Blob-binary large object and stores 4gb of binary data. Using a single character normalizes the table but it costs an additional lookup to obtain the actual value. Range control means to apply validation rules and limitations. Referential integrity means we need a primary-foreign key matchup. Fo(cid:396) (cid:396)efe(cid:396)e(cid:374)(cid:272)e data, we li(cid:374)k p(cid:396)i(cid:373)a(cid:396)y keys f(cid:396)o(cid:373) diffe(cid:396)e(cid:374)t ta(cid:271)les, so you do(cid:374) t (cid:374)e(cid:272)essa(cid:396)ily (cid:374)eed to have the same primary key for both tables. Denormalization usually complicates things but it helps save some time and details for join statements.