DBMS

10 articles in this topic

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.

Updated 14 Jul 20265 min readDBMS

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.

Updated 14 Jul 20265 min readDBMS

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.

Updated 14 Jul 20267 min readDBMS

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 ACID, and indexing, each answered with the natural follow-up so rote definitions become explanations.

Updated 14 Jul 20269 min readDBMS

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.

Updated 14 Jul 20265 min readDBMS

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.

Updated 14 Jul 20265 min readDBMS

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.

Updated 14 Jul 20265 min readDBMS

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.

Updated 14 Jul 20265 min readDBMS

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.

13 Jul 20265 min readDBMS

DBMS Normalization Explained Simply (With the Questions That Test It)

Normalization confuses almost everyone the first time. Here is a plain-English walk from functional dependencies to BCNF, and the exact question patterns that test it.

Updated 10 Jul 20266 min readDBMS