Lesson 7: Database Administration

Database administration includes managing who can do what. A DBA (Database Admin) creates user accounts and assigns privileges (e.g. SELECT, INSERT, UPDATE) on tables. In SQL, GRANT SELECT ON Student TO user1; gives permission to view the Student table. Roles (groups of privileges) are often used. Strong passwords and encrypting sensitive columns (like citizens' personal identifiers under PH law) are part of security too. In exams, you may list common grants or be asked how to prevent unauthorized data access.

An index is like a book's index: it speeds up data retrieval. Creating an index on a column (e.g. CREATE INDEX idx_name ON Student(name);) helps queries that search by name. However, indexes take storage space and slow down updates/inserts (every change must update the index). Use indexes on columns that are often searched or joined. In database admin questions, know that a PRIMARY KEY automatically creates a unique index. You might be asked the effect of an index or how it helps a query run faster (lower search time).