CS Fundamentals
451 articles in this topic
SQL OUTER JOINs: LEFT, RIGHT, and FULL with Worked Examples
Learn outer joins from a five-employee, four-department dataset. Trace preserved rows, NULLs, filter placement, row counts, and four exact exercise answers.
Updated 20 Sep 20266 min readDBMS
Closure Properties of Formal Languages: Worked Examples and Exam Traps
Learn what closure means at the language-class level. Build a product DFA, disprove CFL intersection closure, and use known results without falling into common traps.
Updated 20 Sep 20265 min readTheory of Computation
Basic Addressing Modes in Computer Architecture: Worked Effective-Address Examples and Exam Traps
Stop mixing up the instruction field, effective address, and operand. Reuse one machine state to calculate each basic addressing mode step by step.
Updated 20 Sep 20266 min readComputer Organization & Architecture
Multiplexers (MUX): Selection Logic, Boolean Function Realization and GATE Worked Examples
Learn how a MUX selects data, realizes Boolean functions, and scales through cascading. Trace two exact circuits and repair the mistakes that usually change the answer.
Updated 20 Sep 20265 min read100 viewsDigital Logic
C Structures: Declaration, Initialization and Union Comparison with Worked Examples
Learn what a structure declaration creates, how each initializer form behaves, and why a union makes a different storage promise. Worked traces cover pointers, copying, padding and tagged unions.
Updated 19 Sep 20265 min readC Programming & Data Structures
Cloud Storage and Databases Explained: Models, Replication and Worked Examples
Understand when to use object, block or file storage and when a database fits better. Follow two reproducible examples for IoT capacity and replica quorums.
Updated 19 Sep 20266 min readComputer Networks
Operator Precedence Parsing: Build the Table and Parse an Expression Step by Step
Build an operator-precedence table from a grammar, then use it to trace every shift and reduction for i+i*i.
Updated 19 Sep 20266 min readCompiler Design
Definition of a Function: Domain, Codomain, Range and Counting Formula
Build the definition from first principles, separate the three sets, verify one finite map, and count all functions before handling common restrictions.
Updated 19 Sep 20266 min readEngineering Mathematics
Windows OS Architecture: Processes, Memory, NTFS and Worked Examples
Follow one coherent map of Windows OS architecture, then solve thread scheduling, virtual-address translation and NTFS allocation examples step by step.
Updated 19 Sep 20266 min readOperating Systems
ORDER BY and LIMIT in SQL: Tutorial with Exact Outputs
Learn to sort SQL results deterministically, resolve ties, select top rows, and paginate with LIMIT and OFFSET using one eight-row orders table.
Updated 19 Sep 20266 min readDBMS
CFL Identification: Decision Rules, Worked Examples and Exam Traps
Learn a repeatable way to classify context-free languages, from constructive grammar and stack evidence to safe closure arguments and a complete non-CFL proof.
Updated 19 Sep 20267 min readTheory of Computation
Cache Mapping Techniques and Memory Units: Direct, Associative and Set-Associative Worked Example
Use one address to learn memory-unit conversion, cache organisation and the exact tag, index and offset fields for all three mapping techniques.
Updated 18 Sep 20266 min readComputer Organization & Architecture