Question 1

Three-tier architecture benefits: Which statement best captures a key benefit of adopting a three-tier (presentation, application, data) architecture in enterprise systems?

Accepted Answer

Introduction / Context: Three-tier architecture separates responsibilities into presentation (UI), application (business logic), and data (DB). This separation improves maintainability, scalability, and the ability to evolve systems without disrupting all layers. Given Data / Assumptions: Business logic can live on an application server. Multiple client types (web, mobile) may consume the same services. The database focuses on persistence and set-based processing. Concept / Approach: Modularity enables adding new business modules (APIs/services) without altering clients extensively. Centralizing logic on an app tier lightens the client and can reduce ad-hoc burdens on the DB, effectively making both “thinner.” While compiled SQL performance mainly depends on the database, three-tier designs facilitate pooling, caching, and optimized call patterns that indirectly improve performance of repeated statements. Step-by-Step Solution: Abstract business rules into services on the app tier.Share services across multiple UIs; keep clients thin.Use connection pooling/caching to reduce DB round-trips. Verification / Alternative check: Measure throughput after introducing an app tier with pooled connections and cached results; observe reduced DB contention. Why Other Options Are Wrong: Options A and C are true on their own; B is plausible via better call patterns and reuse—hence “All of the above.” Common Pitfalls: Assuming three tiers automatically improve performance without proper design; duplicating logic across tiers. Final Answer: All of the above.

Question 2

Understanding JDBC: Which statement about Java Database Connectivity (JDBC) is accurate with respect to purpose and design?

Accepted Answer

Introduction / Context: JDBC is the standard Java API for interacting with relational databases. It abstracts vendor-specific protocols via drivers, allowing Java applications to execute SQL and manage connections in a portable way. Given Data / Assumptions: Audience: Java developers connecting to RDBMS systems. JDBC defines interfaces and classes in the Java language. Vendors supply JDBC drivers that implement the API. Concept / Approach: JDBC is conceptually similar to ODBC (Open Database Connectivity) in that both define a standard interface to access different databases through drivers. However, JDBC is Java-specific; it is not language independent and is not intended for non-Java languages. Step-by-Step Solution: Identify the role of JDBC: a Java API to issue SQL, manage connections, handle results.Compare with ODBC: both use drivers to hide vendor specifics.Conclude that “similar in concept to ODBC” is accurate. Verification / Alternative check: Review JDBC architecture diagrams showing JDBC API → Driver Manager → JDBC Driver → DBMS, analogous to ODBC APIs and drivers. Why Other Options Are Wrong: Language independent / useful for all OO languages: false; JDBC is for Java. Three main layers: oversimplification and not a canonical truth for JDBC itself. Common Pitfalls: Confusing the JDBC-ODBC bridge (deprecated) with general JDBC usage; assuming drivers behave identically across vendors without testing. Final Answer: It is similar in concept to ODBC.

Question 3

Application logic components in multi-tier systems: Which trio names the three primary components of application logic most commonly referenced in system design?

Accepted Answer

Introduction / Context: Logical separation clarifies responsibilities and enables scaling. Most system designs describe three application logic components that align with how requests are handled and persisted across tiers. Given Data / Assumptions: Design targets multi-tier web or enterprise systems. We are naming logical responsibilities, not physical machines. Each component can map to one or more tiers. Concept / Approach: The canonical trio is Presentation (UI/interaction), Processing (business logic/computation), and Storage (data persistence). “Client” is a role rather than a logic component; “Network” is infrastructure, not application logic. Step-by-Step Solution: Identify user-facing concerns → Presentation.Identify rules/workflows → Processing.Identify persistence → Storage. Verification / Alternative check: Map to MVC and 3-tier patterns: View ~ Presentation, Controller/Service ~ Processing, Model/Repository ~ Storage. Why Other Options Are Wrong: Options containing “Client” mix roles with logic; “Network” is not application logic. Common Pitfalls: Conflating physical deployment (tiers) with logical responsibilities; overloading the database with business logic. Final Answer: Presentation, Processing, and Storage

Question 4

Server roles across layers: At which layer can a “server” not serve in a multi-tier application stack from a role perspective?

Accepted Answer

Introduction / Context: In multi-tier systems we distinguish client, application (business), and data (database) layers. The term “server” typically denotes a service-providing role rather than the consumer UI. Given Data / Assumptions: Client layer is the consumer (e.g., browser, mobile app). Business layer exposes services and logic. Database layer stores and serves data. Concept / Approach: A server provides resources or services to clients. Therefore, it naturally belongs to the business (application) layer or the database layer. The client layer is a consumer, not a provider, so a “server” does not serve there by definition. Step-by-Step Solution: Define roles: providers vs. consumers.Map providers to business/database; consumer to client.Conclude the client layer is not where servers serve. Verification / Alternative check: Architectural diagrams show load balancers → app servers → DB servers, with user agents (clients) at the edge. Why Other Options Are Wrong: Business and Database layers are exactly where servers operate. “All of the above” contradicts the existence of app/DB servers. Common Pitfalls: Confusing physical devices (client machines) with logical roles; calling a heavy desktop “server.” Final Answer: Client Layer

Question 5

Client/server security scope: Which option best summarizes the breadth of security controls expected in a well-managed client/server environment?

Accepted Answer

Introduction / Context: Client/server security spans facilities, processes, and technology. A robust posture layers controls from the data center to the code deployment pipeline and endpoint hardening. Given Data / Assumptions: Enterprise systems with multiple tiers and environments. Compliance and audit expectations. Defense-in-depth strategy. Concept / Approach: Security includes physical safeguards (access badges, CCTV, locked racks), process controls (change management, approvals, versioning), and technical measures across all systems (patching, least privilege, encryption in transit/at rest, monitoring). Effective programs address all these areas, not just one. Step-by-Step Solution: Establish physical controls to protect hardware and facilities.Implement change control to prevent unauthorized or risky deployments.Apply system-wide hardening, identity management, and monitoring. Verification / Alternative check: Audit frameworks (e.g., ISO 27001, SOC 2) require controls spanning physical, administrative, and technical domains. Why Other Options Are Wrong: Each single option is necessary but insufficient alone; comprehensive security requires all. Common Pitfalls: Focusing only on firewalls while neglecting change control or physical access; weak patch management on clients. Final Answer: All of the above.

Question 6

Networked Systems — File Server Characteristics Which statement best describes a core characteristic of a file server in a distributed environment?

Accepted Answer

Introduction: File servers are foundational components in networked computing. They centralize storage and file-system services so that multiple client machines can read, write, and share files over a local or wide area network. This question checks your understanding of what a file server actually does versus the roles of clients and application servers. Given Data / Assumptions: A file server exposes shared folders and files to multiple client machines. Clients access files via standard protocols (for example, SMB/CIFS, NFS). Application logic typically runs on the client or a separate application server, not on the file server. The term “fat client” refers to client machines doing substantial local processing, not to the server. Concept / Approach: The essence of a file server is centralized file-system management and network sharing. Clients authenticate, then open, read, and write files through the server, which handles permissions, locking, and I/O scheduling. By contrast, an application server executes business logic, while a database server manages structured data and queries. Step-by-Step Solution: 1) Identify which option emphasizes centralized file operations available to multiple users.2) Eliminate options that incorrectly describe the server as a “fat client.”3) Eliminate options that limit the server to a single PC, which contradicts its networked nature.4) Select the option that matches a shared, network-accessible file service role. Verification / Alternative check: In common deployments, Windows Server with SMB shares or Linux with NFS exports illustrate exactly this centralized sharing model accessed by many clients concurrently. Why Other Options Are Wrong: Limited to one PC: Contradicts the idea of network sharing. Acts as a fat client: A server is not a “client”; fat clients are endpoints doing heavy local processing. Fat client and limited/shared: Mislabels the server role entirely. Common Pitfalls: Confusing a file server with an application or database server and assuming it runs end-user business logic. Final Answer: Manages file operations and is shared on a network.

Question 7

Open Database Connectivity (ODBC) — Core Purpose and Components Which statement best captures what ODBC provides and requires across different database systems?

Accepted Answer

Introduction: ODBC (Open Database Connectivity) is a widely adopted standard that allows applications to access different relational databases through a uniform API. This question tests whether you recognize both the API's goal (vendor neutrality) and the practical requirements (drivers and connection criteria). Given Data / Assumptions: ODBC defines a common function-call interface for SQL database access. Vendors supply ODBC drivers that translate generic ODBC calls into DBMS-specific protocols. Connections require configuration (DSN/DSN-less), credentials, and driver selection. Concept / Approach: Evaluate whether each statement reflects ODBC realities: vendor drivers are necessary; connections require parameters (driver, server, credentials); and the API abstracts DBMS details so the same code can target multiple systems with appropriate drivers. Step-by-Step Solution: 1) Confirm ODBC's purpose: common API across heterogeneous DBMSs.2) Verify the driver model: vendors implement drivers to bridge ODBC calls to their engines.3) Validate connection prerequisites: connection strings/DSNs and authentication data are required.4) Since all three are true, choose “All of the above.” Verification / Alternative check: Typical connection strings specify Driver, Server, Database, UID, and PWD. Without a suitable driver, ODBC cannot communicate with the DBMS. Why Other Options Are Wrong: Vendor driver only: True but incomplete. Criteria to connect only: True but incomplete. Common API only: True but incomplete. Removes the need for any driver: False; the driver layer is essential. Common Pitfalls: Assuming ODBC magically removes drivers or configuration; it standardizes the interface but still depends on drivers and correct connection parameters. Final Answer: All of the above.

Question 8

APIs and Data Access — What Is an API in the Database Context? In enterprise systems, which statement best describes an Application Programming Interface (API) as it relates to database access?

Accepted Answer

Introduction: An Application Programming Interface (API) defines programmatic contracts that software can call to perform tasks. In data engineering, APIs are crucial for connecting applications to databases in a consistent, maintainable way. This question clarifies what an API means in the database-access context. Given Data / Assumptions: APIs expose functions, classes, or endpoints that applications call. Database APIs (for example, ODBC, JDBC, vendor SDKs) standardize data access. APIs may be packaged as libraries, drivers, or middleware. Concept / Approach: Distinguish between API as a general concept and specific implementations like ODBC/JDBC. An API can be a specification or a concrete library that provides standardized calls to connect, send queries, and retrieve results from a DBMS. Step-by-Step Solution: 1) Recognize that ODBC and JDBC are examples of database-access APIs.2) Understand that “API = same thing as ODBC/JDBC” is too narrow; those are specific APIs, not the definition of API itself.3) Select the option that states an API provides standardized database access, often delivered as middleware or a callable interface. Verification / Alternative check: Developers routinely import database API libraries, create connections, prepare statements, and fetch result sets through those APIs across languages and platforms. Why Other Options Are Wrong: Same as ODBC/JDBC: Conflates specific APIs with the general concept. No DB access: Opposite of what database APIs do. Visual ER tool only: ER tools are modeling aids, not runtime access APIs. Common Pitfalls: Assuming one vendor's API equals the definition of API; remember API is a broad concept encompassing many implementations. Final Answer: Middleware (or a callable interface) that provides standardized access to a database.

Question 9

Stored Procedures — Advantages for Integrity and Architecture Which of the following is a valid advantage of using stored procedures across multiple applications?

Accepted Answer

Introduction: Stored procedures centralize business rules and data manipulation logic inside the DBMS. They are often reused by many applications, which improves consistency, security, and performance. This question asks you to identify a genuine advantage among several distractors. Given Data / Assumptions: Stored procedures can be parameterized and permissioned. Execution plans are typically cached by the DBMS. Reusing the same code path promotes consistent validations and side effects. Concept / Approach: The key benefit is standardized, centralized logic: validations, constraints, and transformations live in one place. That improves data integrity compared to duplicating logic across many client apps. Procedures may also reduce network traffic by sending parameters instead of large ad-hoc SQL strings and can enhance security by limiting direct table access. Step-by-Step Solution: 1) Compare each option against known stored procedure benefits.2) Identify the option that increases integrity through reuse and central control.3) Eliminate options that contradict typical benefits (for example, increased network traffic). Verification / Alternative check: Operational patterns show organizations standardize complex updates in procedures to avoid drift and inconsistencies across many applications and services. Why Other Options Are Wrong: Longer to write than VB: Effort depends on context; not a general truth or advantage. Network traffic increases: Usually decreases; only parameters are sent. Thicker clients: Centralizing logic in the DB often thins clients. Cannot be compiled/cached: DBMSs cache execution plans for procedures. Common Pitfalls: Duplicating logic in many applications causes divergence and integrity issues; stored procedures mitigate this risk. Final Answer: Data integrity improves as multiple applications reuse the same vetted stored procedure.

Question 10

Database Server Responsibilities — Storage vs. Logic vs. Presentation Which responsibility correctly belongs to a database server in a multi-tier architecture?

Accepted Answer

Introduction: In layered architectures, each tier has a distinct responsibility. The database server specializes in persistence and query processing. Confusing these boundaries leads to poor system design and performance bottlenecks. This question clarifies which responsibilities belong to the data tier versus the presentation tier. Given Data / Assumptions: The database server hosts the DBMS and underlying storage structures. It parses, optimizes, and executes SQL; manages transactions and locks. It does not render user interfaces; the presentation layer handles UI. Concept / Approach: Map each task to the correct tier. Storage and data processing are the core domain of the DB server. Presentation logic (UI rendering, HTML generation, view composition) belongs to the client or application/presentation tier. Step-by-Step Solution: 1) Associate database storage with the data tier.2) Associate SQL parsing, optimization, and execution with the DBMS on the data tier.3) Exclude UI rendering from the DB tier; that is the role of the presentation tier.4) Therefore, the correct grouping is A and B only. Verification / Alternative check: DBMS manuals and architecture diagrams depict the server responsible for persistence, indexes, caching, concurrency, and transactions—not screen rendering. Why Other Options Are Wrong: Presentation logic: Not a DB server role. All of the above: Incorrect because it includes presentation. Only A or only B: Too narrow; the DB server does both storage and data processing. Common Pitfalls: Embedding presentation code in stored routines blurs separation of concerns and complicates maintainability. Final Answer: Both A and B only (not presentation logic).

Question 11

Three-Tier Architecture — Layer Composition What does a classic three-tier application architecture include?

Accepted Answer

Introduction: Three-tier architectures separate concerns into presentation (client), application (business logic), and data (persistence). This structure improves scalability, maintainability, and team specialization. The question checks whether you can identify the correct tier composition. Given Data / Assumptions: Presentation focuses on UI and interaction. Application (middle) tier hosts business rules and orchestration. Data tier manages storage, transactions, and integrity. Concept / Approach: Recognize that “three-tier” explicitly means 1 client-side tier and 2 server-side tiers. Options listing only server layers or only client layers misunderstand the model. Step-by-Step Solution: 1) Identify the roles: client (UI), application (logic), data (DBMS).2) Match the description that includes exactly these three roles.3) Select the option that states one client layer and two server layers. Verification / Alternative check: Reference diagrams for web apps: browser (presentation), application server (logic), database server (data) are the canonical example. Why Other Options Are Wrong: Three server layers / two client layers / three client layers: Misrepresent the distribution of responsibilities. Monolithic tier: Opposite of three-tier separation. Common Pitfalls: Confusing “n-tier” with mere horizontal scaling of identical servers; tiers describe functional separation, not just server count. Final Answer: A client (presentation) layer and two server layers (application and data)

Question 12

Mainframes in Modern IT — Role and Characteristics Which statement about mainframe computing is accurate in comparison to client/server systems?

Accepted Answer

Introduction: Mainframes remain central to many enterprises for high-volume transaction processing and reliability. This question distinguishes enduring mainframe traits from misconceptions and conflations with client/server computing. Given Data / Assumptions: Mainframes emphasize throughput, I/O capacity, and reliability. Client/server distributes logic across clients and servers. Enterprises often keep core ledgers and transaction systems on mainframes. Concept / Approach: Identify the statement that reflects real-world deployment trends. Mainframes and client/server are different paradigms. While modernization exists, many mission-critical workloads (banking, airlines, insurance) continue to run on mainframes due to SLAs, performance, and operational maturity. Step-by-Step Solution: 1) Reject equivalence with client/server—architectures differ.2) Reject statements that describe client/server partitioning decisions as unique to mainframes.3) Select the option about mission-critical systems persisting on mainframes. Verification / Alternative check: Industry surveys and vendor case studies cite long-lived mainframe cores, often exposed via APIs or integration layers to modern applications. Why Other Options Are Wrong: Same as client/server: False; architectural principles are different. Workstation/server code decisions: That is a client/server concern, not a mainframe hallmark. All of the above: Includes false statements. Cannot handle scale: Opposite of mainframe strengths. Common Pitfalls: Assuming modernization always means abandoning mainframes; in reality, coexistence and integration are common. Final Answer: Mission-critical systems have tended to remain on mainframes.

Question 13

Query By Example (QBE) — Capabilities and Limitations Which statement about QBE (Query By Example) is accurate in practice?

Accepted Answer

Introduction: QBE (Query By Example) lets users compose database queries through a tabular or form-based interface instead of writing query text. This question separates realistic capabilities of QBE from common misconceptions and exaggerations. Given Data / Assumptions: QBE is often implemented in tools like Microsoft Access and some ER/BI tools. It is meant to simplify query creation for users and analysts. QBE is not a complete application framework. Concept / Approach: We look for the statement that accurately positions QBE as a visual query builder, not an application development platform, and not a universal standard with guaranteed performance advantages. Step-by-Step Solution: 1) Eliminate claims of a universal standard—no single cross-vendor QBE standard exists.2) Eliminate the claim that QBE cannot be used with client/server; it can be used to drive client/server queries.3) Eliminate the statement denying a visual environment; visualization is QBE’s core feature.4) Select the statement acknowledging QBE as a visual query tool, not a full app platform, and not inherently faster than SQL. Verification / Alternative check: Tools expose QBE-like designers that generate SQL under the hood; full applications still require UI, logic, and deployment frameworks beyond QBE. Why Other Options Are Wrong: Official universal standard: No such global standard. Cannot be used for client/server: Incorrect; QBE-generated queries can target client/server DBMSs. No visual environment: Contradicts QBE’s essence. Guaranteed performance: Performance depends on the resulting SQL and database design, not the query builder UI. Common Pitfalls: Assuming a visual tool replaces knowledge of schemas or indexing; understanding data structures still matters for effective queries. Final Answer: QBE is a visual approach to constructing queries; complete end-to-end applications are not generally built using QBE alone.

Question 14

Symmetric Multiprocessing (SMP) — Characteristics and Use Cases Which statement correctly describes an aspect of symmetric multiprocessing systems?

Accepted Answer

Introduction: Symmetric multiprocessing (SMP) places multiple identical processors under a single operating system image with shared memory. This question checks whether you can identify a true statement about SMP while avoiding common misconceptions about OS copies and contention. Given Data / Assumptions: In SMP, processors share main memory and I/O under one OS instance. Workloads with shared in-memory data can benefit from parallel CPUs. Shared resources require synchronization to avoid corruption. Concept / Approach: Validate which statement matches SMP basics: a single OS image coordinates multiple CPUs; shared memory enables parallel processing of common datasets; contention and synchronization are realities to be managed—not eliminated. Step-by-Step Solution: 1) Reject the idea of per-CPU independent OS copies; SMP uses one OS instance.2) Recognize that shared in-memory data is a prime SMP use case—select this option.3) Statements about uniprocessor bottlenecks are too generic and not a defining property of SMP.4) Reject claims that SMP removes contention or synchronization needs—these remain important concerns. Verification / Alternative check: OS kernels for SMP include scheduler and locking mechanisms to coordinate cores accessing shared memory and kernel structures. Why Other Options Are Wrong: Per-CPU OS copy: Describes cluster/MPP, not SMP. Uniprocessor bottlenecks statement: Not specific to SMP and overbroad. No memory contention / no locks: Unrealistic; synchronization is essential in SMP. Common Pitfalls: Confusing SMP with distributed systems, or assuming parallelism eliminates the need for careful concurrency control. Final Answer: SMP is useful for workloads where large shared data structures must remain in memory and be processed concurrently.

Question 15

Client/Server Essentials — What Is Not Required? Which of the following is NOT necessary to implement a client/server system?

Accepted Answer

Introduction: Client/server is a flexible architectural pattern in which client applications consume services provided by servers over a network. Many elements contribute to a successful deployment, but not every environment needs a file server. This question identifies the item that is not strictly required. Given Data / Assumptions: Client/server emphasizes service endpoints (for example, application and database servers). Middleware and tools must interoperate. Network capacity and security must be planned. A file server is optional, depending on use case. Concept / Approach: Differentiate hard requirements from optional components. Middleware compatibility, requirement analysis, bandwidth planning, and protocol/security choices are baseline needs. A file server is only necessary if the solution explicitly requires shared file storage; many client/server systems operate without any file shares at all. Step-by-Step Solution: 1) Mark requirement analysis and bandwidth checks as universal planning tasks.2) Confirm middleware/tool compatibility is essential for connectivity and deployment.3) Recognize that file servers are not mandatory in architectures centered on APIs, application servers, and databases.4) Choose the file-server option as “not necessary.” Verification / Alternative check: Modern web systems commonly use application and database servers without any SMB/NFS file shares; object storage or embedded storage may suffice. Why Other Options Are Wrong: Middleware/tool interoperability: Required to ensure components can communicate. Understanding requirements: Fundamental to any system design. Bandwidth capability: Impacts performance and viability. Protocol/security selection: Core to interoperability and protection. Common Pitfalls: Assuming every networked system needs shared file storage; many are purely service- and API-driven. Final Answer: Include the use of a file server.

Question 16

Is Query-by-Example (QBE) the most widely available direct-manipulation (graphical) database query interface across end-user tools?

Accepted Answer

Introduction / Context: Query-by-Example (QBE) popularized the idea that users can construct queries by filling in example values or selecting fields in a grid rather than writing textual SQL. Many end-user tools (e.g., Microsoft Access-style query designers, visual query builders in BI platforms) follow QBE-like patterns. Given Data / Assumptions: “Direct-manipulation” emphasizes graphical selection of tables/fields/criteria. Widespread in desktop database tools and many BI suites. Underlying engines still generate SQL or equivalent queries. Concept / Approach: QBE provides a visual canvas where users drag tables, specify joins, set filters, and choose aggregates. The interface generates the textual query behind the scenes, making relational querying accessible to non-programmers. Step-by-Step Solution: User selects tables/joins visually.User specifies criteria (e.g., city = “Boston”).Tool composes SELECT, FROM, JOIN, WHERE, GROUP BY accordingly.User previews results and iterates without hand-writing SQL.Tool translates final design into an executable query sent to the DBMS. Verification / Alternative check: Survey common office/BI suites; most offer a QBE-style builder or “visual query” mode for non-technical users, confirming the paradigm’s wide availability. Why Other Options Are Wrong: Claiming only SQL editors exist (option b) ignores pervasive visual designers. Options c, d, and e artificially limit QBE to specific platforms; in practice, QBE front-ends target many relational engines. Common Pitfalls: Assuming QBE can express every advanced SQL construct; overlooking performance implications of auto-generated queries; relying solely on visual tools without understanding joins and cardinality. Final Answer: Applies — QBE is a widely available direct-manipulation query paradigm

Question 17

In massively parallel processing (MPP) database systems, does each processing node require its own operating system instance resident in the node’s local memory?

Accepted Answer

Introduction / Context: MPP architectures distribute data and queries across many independent nodes. Each node has its own CPU, memory, and storage and executes parts of a query in parallel. This independence extends to the operating system: each node boots and runs its own OS. Given Data / Assumptions: Each node has dedicated memory and local resources. Communication happens over a high-speed network fabric. Contrast with SMP (shared-memory) systems where CPUs share memory and a single OS instance. Concept / Approach: Because MPP nodes are loosely coupled, the OS image (and DBMS process) resides on each node, managing the node’s resources. The DBMS coordinates parallel tasks across nodes via messaging, but the OS is not shared across the cluster as a single image. Step-by-Step Solution: Provision node hardware or VMs with CPU, memory, and storage.Install/boot an OS instance on each node.Install DBMS worker/segment processes per node.Distribute data and assign query fragments to nodes in parallel.Aggregate results via interconnect to return to the coordinator. Verification / Alternative check: Vendor documentation for MPP databases (e.g., Teradata-like architectures) describes per-node OS instances managing local memory and processes, validating the statement. Why Other Options Are Wrong: A single shared OS image (option b) describes SSI or SMP-like models, not classic MPP. Options c–e mis-scope the concept; MPP is about node independence regardless of virtualization or in-memory features. Common Pitfalls: Confusing MPP with shared-nothing vs. shared-memory; assuming OS-level memory sharing across nodes; underestimating network bottlenecks in shuffle phases. Final Answer: Applies — each MPP node runs its own OS instance

Question 18

In client/server computing, a local area network (LAN) connects personal computers that have their own storage while also enabling them to share printers, file shares, applications, and other services attached to the LAN. Does this description apply?

Accepted Answer

Introduction / Context: Client/server environments rely on networks to connect user devices (clients) to shared resources hosted on servers. A LAN provides the communication fabric so clients can access printers, file servers, databases, application servers, and web services while still retaining local storage and processing. Given Data / Assumptions: Clients are PCs with their own CPUs, memory, and local disks. Servers publish shared services (file, print, application, database). The LAN may be wired or wireless; topology is not critical to the definition. Concept / Approach: Client/server separates concerns: user interface and some logic execute on clients; centralized services and data reside on servers. LAN connectivity (Ethernet/Wi-Fi) enables resource sharing, authentication, and centralized administration alongside local capabilities on each PC. Step-by-Step Solution: Clients join the LAN with IP configuration.Servers advertise resources via network protocols.Clients access shared devices or software while still saving files locally if permitted.Directory services apply policies and permissions across the LAN.Applications may use database connections over the LAN to a DB server. Verification / Alternative check: Observe common office networks: users print to shared printers and access shared drives while also using local drives, matching the description. Why Other Options Are Wrong: Option b denies basic LAN sharing capabilities. Option c is needlessly restrictive; wired/wireless both qualify. Option d contradicts “client/server.” Option e confuses LANs with thin-client or diskless environments, which are optional. Common Pitfalls: Assuming all processing must be server-side; ignoring security and access control; overlooking bandwidth and QoS needs for database-heavy applications. Final Answer: Applies — that is a correct description of client/server LANs

Question 19

Within a client/server database architecture, is the database server responsible for storage allocation, access (concurrency/locking), and query processing?

Accepted Answer

Introduction / Context: Database servers centralize critical data services. They own persistent storage, enforce transactional integrity, coordinate concurrency control, and execute query plans. Clients submit requests; the server performs the heavy lifting to ensure correctness and performance. Given Data / Assumptions: DB server hosts data files, logs, and system catalogs. Server engines implement locking, latching, MVCC, or equivalent. Server compiles and executes SQL, optimizing access paths. Concept / Approach: This centralization enables consistent backups, security policies, and performance tuning. Clients focus on presentation and some application logic; the DB server ensures reliable data management and scalable query execution. Step-by-Step Solution: Client sends a query/transaction request.Server parses and optimizes the request to a plan.Server accesses storage via buffer/cache managers and executes operators.Server enforces isolation/consistency and writes to logs/data files.Server returns results to the client. Verification / Alternative check: Monitoring tools on the DB server display I/O, buffer usage, lock waits, and CPU used by query execution — evidence that storage, access, and processing occur on the server. Why Other Options Are Wrong: Options b–e incorrectly push server responsibilities to clients; while client-side logic exists, data storage and core processing remain server duties in typical architectures. Common Pitfalls: Overburdening the server with avoidable computations; under-sizing buffer pools; poor index design causing excessive I/O. Final Answer: Applies — the server manages storage, access, and processing

Question 20

Does the term “fat client” describe a PC that handles UI and substantial application processing and typically includes meaningful local storage (as opposed to none or minimal storage)?

Accepted Answer

Introduction / Context: Client classifications describe how much work and data reside on the user device. A “fat client” (also called thick client) performs substantial processing locally and commonly stores data/configuration locally. A “thin client” minimizes local state and computation, relying heavily on servers. Given Data / Assumptions: Fat clients run rich applications natively (desktop apps, native mobile apps). Local storage may include caches, datasets, offline files, or application binaries. Thin clients offload most logic and storage to servers or remote desktops. Concept / Approach: The statement claims fat clients have no or limited local storage, which conflates fat with thin clients. In practice, fat clients leverage local CPU/GPU and disk/flash to improve responsiveness, enable offline capability, and reduce server load. Step-by-Step Solution: Identify fat client traits: rich UI, local processing, local storage.Contrast with thin client traits: lightweight UI, server-side processing, minimal local data.Evaluate the statement: it describes thin clients, not fat clients.Therefore, the claim does not apply. Verification / Alternative check: Examples: full-featured desktop accounting software or CAD tools store significant local data and perform intensive processing — classic fat clients. Browser-based SaaS with minimal local storage aligns with thin clients. Why Other Options Are Wrong: Option b restates the incorrect definition. Options c and d misclassify thin/browser or VDI models as fat clients. Option e is incorrect; fat clients, by definition, execute logic locally. Common Pitfalls: Mislabeling clients can lead to poor architecture choices: e.g., assuming offline capability where none exists, or underestimating server load for thin clients. Final Answer: Does not apply — a fat client usually includes significant local storage

The Client-Server Database Questions