DBMS
20 articles in this topic
Data Warehousing and Data Mining in DBMS: Star Schema, OLAP Operations and Apriori with Worked Examples
Move from warehouse vocabulary to hand-worked answers. Build a star schema, operate on a data cube, run Apriori, and follow two k-means iterations.
Relational Calculus in DBMS: Tuple and Domain Calculus Explained with Worked Examples
Learn TRC and DRC through one small database, then trace existential and universal queries without getting caught by quantifier or safety mistakes.
File Organization and Indexing in DBMS: Complete Guide with Worked Block-Access Examples
Carry one 30,000-record EMPLOYEE file through heap, ordered, indexed, B+ tree, and hash access paths. See where every block-access figure comes from.
SQL Tutorial: The Complete Learning Path from First Query to Transactions
Learn SQL in a deliberate order, using one small dataset to practise table creation, filtering, joins, grouping, subqueries and transactions.
CNF and GNF for GATE: CFG Simplification and Normal-Form Conversion, Step by Step
Run epsilon, unit and useless-production removal in the right order, convert one full grammar to CNF, and verify the two derivation-count formulas.
SQL Window Functions Explained: ROW_NUMBER, RANK, and DENSE_RANK with Interview Problems
See why window functions preserve rows, then calculate three ranking columns on the same tied-score table.
File Organization and Indexing in DBMS for GATE: Dense, Sparse, Primary and Secondary Indexes
Build one sorted file, count its blocks, and index it in enough ways to make dense, sparse, primary, secondary, and multilevel questions routine.
SQL Subqueries and Correlated Subqueries: How to Read, Write and Solve Placement-Test Questions
Read nested SQL from the inside out, distinguish once-only and per-row evaluation, and solve common placement questions with one small employee dataset.
GROUP BY and HAVING in SQL: Aggregation Questions from Placement Tests, Solved Step by Step
Trace two placement-style SQL queries from raw rows to grouped results. Learn exactly when to use WHERE, HAVING, COUNT(*), and COUNT(column).
Cyber Threats and Malware Attacks: Types, Attack Chains and a Worked Incident
Learn to separate vectors, techniques and payloads, classify mixed malware behaviour, calculate exposure, and map controls to each incident stage.
Relational Algebra for GATE: Operators, Tuple-Counting and Query Equivalence Drills
Calculate set, join, and outer-join cardinalities on concrete relations, then use selection and projection pushdown without changing query meaning.
ER Model to Relational Mapping for GATE: Minimum Number of Tables Questions Solved
Count the minimum relations from cardinality and participation, then check the special rules for weak entities, relationship attributes, and multivalued attributes.