Proper use of foreign keys can minimize data redundancy and chance chance of destructive anomalies. However, concerns of efficiency and convenience can sometimes result in redundant data design despite the risk of corrupting the data. A solution to the problem is is to to place place the redundant data in in a separate table, table, one in which the data data no no longer will be redundant. How do database management system ensure data security and privacy ? A database management system ensure data security and privacy by ensuring that only means of access to the database is through the proper channel and also by carrying out authorization checks whenever access to sensitive data is attempted. What are the three levels of data abstraction? a. External Level (View Level) What do you understand by data independence? Data independence allows modification of a scheme definition in one level without affecting a scheme definition in the next higher level. What are the two types of data independence? independence? How they different? There are two levels of data independence: Physical and Logical. Physical Data Independence modifies the scheme followed at the physical level without affecting the scheme followed at the conceptual level. Whereas Logical Data Independence modifies the conceptual scheme without causing any changes in the schemes followed at view levels.
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