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  1. A database contains an entry with an empty primary key. Which database concept has been violated?
    A. Entity Integrity
    B. Normalization
    C. Referential Integrity
    D. Semantic Integrity

Correct Answer and Explanation: A. Answer A is correct; Entity integrity means each tuple has a unique primary key that is not null.

Incorrect Answers and Explanations: B, C, and D. Answers B, C, and D are incorrect. Normalization seeks to make the data in a database table logically concise, organized, and consistent. Referential integrity means that every foreign key in a secondary table matches a primary key in the parent table: if this is not true, referential integrity has been broken. Semantic integrity means each attribute (column) value is consistent with the attribute data type.

  1. Which vulnerability allows a third party to redirect static content within the security context of a trusted site?
    A. Cross-Site Request Forgery (CSRF)
    B. Cross-Site Scripting (XSS)
    C. PHP Remote File Inclusion (RFI)
    D. SQL Injection

Correct Answer and Explanation: A. Answer A is correct; Cross-Site Request Forgery (CSRF) allows a third party to redirect static content within the security context of a trusted site.

Incorrect Answers and Explanations: B, C, and D. Answers B, C, and D are incorrect. Cross-Site Scripting (XSS): third party execution of Web scripting languages such as Javascript within the security context of a trusted site. XSS is similar to CSRF; the difference is XSS uses active code. PHP Remote File Inclusion (RFI): alters normal PHP variables to reference remote content, which can lead to execution of malicious PHP code. SQL Injection manipulates a back-end SQL server via a front-end Web server.

  1. Which language allows CORBA (Common Object Request Broker Architecture) objects to communicate via a message interface?
    A. Distributed Component Object Model (DCOM)
    B. Interface Definition Language (IDL)
    C. Object Linking and Embedding (OLE)
    D. Object Management Guidelines (OMG)

Correct Answer and Explanation: B. Answer B is correct; Interface Definition Language (IDL) allows CORBA objects to communicate via a message interface.

Incorrect Answers and Explanations: A, C, and D. Answers A, C, and D are incorrect. DCOM (Distributed Component Object Model) is a Microsoft object broker that locates objects over a network. Object Linking and Embedding (OLE) is a part of DCOM that provides a way to link documents to other documents. Object Management Guidelines is a distracter answer, playing off the term OMG: Object Management Group (OMG) developed CORBA.

  1. Which database high availability option allows multiple clients to access multiple database servers simultaneously?
    A. Database commit
    B. Database journal
    C. Replicated database
    D. Shadow database

Correct Answer and Explanation: C. Answer C is correct; Database replication mirrors a live database, allowing simultaneous reads and writes to multiple replicated databases by clients.

Incorrect Answers and Explanations: A, B, and D. Answers A, B, and D are incorrect. DBMSs may attempt to commit updates: make the pending changes permanent. A database journal is a log of all database transactions. A shadow database is similar to a replicated database, with one key difference: a shadow database mirrors all changes made to a primary database, but clients do not access the shadow.

  1. Which component of an expert system consists of “if/then” statements?
    A. Backward chaining
    B. Forward chaining
    C. Inference engine
    D. Knowledge base

Correct Answer and Explanation: D. Answer D is correct; a knowledge base consists of “if/then” statements. These statements contain rules that the expert system uses to make decisions.

Incorrect Answers and Explanations: A, B, and C. Answers A, B, and C are incorrect. Forward chaining starts with no premise and works forward to determine a solution. Backward chaining begins with a premise and works backwards. The inference engine follows the tree formed by knowledge base, and fires a rule when there is a match.