DBMS
25 articles in this topic
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.
SQL Queries for Placement Interviews: Second Highest Salary, Joins and GROUP BY Step by Step
SQL queries for placement interviews built step by step on one schema: second highest salary three approaches, joins with results shown, GROUP BY and HAVING.
DBMS Interview Questions for Freshers: Top 50 with Answers That Survive Follow-Ups
50 DBMS interview questions for freshers, grouped the way interviews actually run: keys, the normalization-to-BCNF-to-denormalization chain, SQL joins, transactions and isolation levels, and indexing, answered as chains so rote definitions become explanations.
IBPS SO IT Officer DBMS: the professional knowledge topics that matter
The DBMS core of the IBPS SO IT Officer Mains Professional Knowledge paper: the ER model, keys, normalization with a worked example, SQL essentials and transactions, and how each is tested.
B+ Trees and Database Indexing: why indexes are fast, with a worked insert
B+ trees and database indexing explained: dense vs sparse, primary clustering and secondary indexes, B-tree vs B+ tree, with a worked B+ tree insert example.
SQL Queries and Joins in DBMS: sublanguages, joins, and GROUP BY worked out
SQL queries and joins in DBMS: DDL DML DCL TCL sublanguages, SELECT and WHERE, inner and outer joins, GROUP BY with HAVING, plus a worked join example.
Transactions and concurrency control in DBMS: ACID, schedules, serializability
Transactions in DBMS explained: ACID properties, schedules, conflict serializability with a worked precedence graph, two-phase locking, and the exam angle.
Normalization in DBMS: 1NF to BCNF, with the exam angle
Normalization in DBMS explained: functional dependencies, the exact 1NF, 2NF, 3NF and BCNF rules, a worked decomposition of one relation, and 3NF vs BCNF.