15 Jan 2022
Day2⃣4⃣of #50daysofDBMS
✅Extended Features of ER:
Non binary Relationship sets
Cardinality on Non binary (1 arrow)
✅Specialization:
overlapping and disjoint
represent into schema:
1) including primary key of higher entity sets
2)including all Attributes of "
1
5
9 Jan 2022
Day 2⃣3⃣of #50daysofDBMS
ER diagram:
-Representation of Entity ,Relationship with attributes,
Roles
Cardinality Constraint:
-directed line: one,Undirected:Many
-Total & Partial Participation,writing MIN_MAX Cardinality
-Dealing with Composite Attributes
-Expressing Weak Entity
1
4
7 Jan 2022
Day 2⃣2⃣of #50daysofDBMS
Design Process of DBMS:
-> Conceptual->Logical->Physical
Design Approaches: ER Model
->Entity sets,Relationship sets,Degree
->Mapping Cardinality:1-1,M-1,1-M,M-M
->Complex Attributes: Simple,Composite,Single & Multivalued,Derived
->Weak Entity sets
4
7 Jan 2022
Day 2⃣1⃣of #50daysofDBMS
Learnt:
Formal Relational Query Language:
->Relational Algebra:
- 8 Operators: select,project,union,set diffrence,x,rename,intersection,division.
->Tuple & Domain Relational Calculus Overview.
-> Equivalence of Algebra and Calculus.
5
1 Jan 2022
Day 2⃣0⃣of #50daysofDBMS
Learnt:
-> Using SQL with Programming Language: JDBC,ODBC,Embedded SQL.
-> Functions and Procedures in SQL
-> Language Constructs
-> Triggers
4
26 Dec 2021
Day 1⃣ 8️⃣of #50daysofDBMS
Learnt
Continuing Intermediate SQL
->Integrity Constraints:
not null, unique, check(Predicate)
->Referential Integrity
on delete <action>
on update <action>
action{cascade, set null, no action, set default}
More on data types:
date,time,timestamp
(1/2)
1
6
26 Dec 2021
Day 1⃣7️⃣of #50daysofDBMS
Learnt:
Intermediate SQL
-> Cross,inner,outer,left,right,natural,equi Join,on and using keyword.
->creating view(virtual relation),creating view using other views, recursive view.
-> intro to Transaction.
3
23 Dec 2021
Day 1⃣6⃣of #50daysofDBMS
Solved:
183. Customers Who Never Order
627. Swap Salary
Continuing Nested Queries:
using in FROM and SELECT.
with clause
Modification of database:
delete,insert,update,set,case condition updates.
5
23 Dec 2021
Day of1⃣5⃣ #50daysofDBMS
Learn about:
-> Nested Queries:
using in WHERE:(in (set membership),some,all(set comparison),
test for empty relation (exists)
test for absence of duplicates(unique)
3
19 Dec 2021
Day 1⃣4️⃣of #50daysofDBMS
Revised topics which i learnt.
Solved:
LC 181. Employees earning more then their Manager
LC 620. Not Boring Movies
4
12 Dec 2021
Day 1⃣3⃣of #50daysofDBMS
Learnt:
ER Diagrams:
-> Converting Data Storage requirements to ER Diagram
to Database Schema.
-> Special Symbols meaning.
-> Weak entity and identity relationship.
-> partitions,cardinality.
-> 5 Steps to convert ER to Schema.
1
11 Dec 2021
Day 1⃣2⃣of #50daysofDBMS
Learn about:
-> Nested Queries
-> Concept of Deleting Records having foreign keys
(ON DELETE SET NULL / CASCADE)
-> Triggers
4
10 Dec 2021
Day 1⃣1⃣of #50daysofDBMS
-> Practiced and learn some more SQL Queries
SOLVED:
175. Combine Two Tables (LC)
182. Duplicate Emails(LC)
595. Big Countries (LC)
2
9 Dec 2021
Day 1⃣0⃣of #50daysofDBMS
-> Setup MYSQL server
-> Practiced and Played with SQL commands which i learn on DAY 8⃣.
5
5 Dec 2021
Day 9⃣of #50daysofDBMS
Learnt:
String operations (like, %,_,||)
Ordering the display of tuples (order by, desc, asc)
comparison (between,tuple)
Set operations (union,intersect,except)
multiset versions of set operation (operation all)
Null values (is null)
Aggregate functions
2
4 Dec 2021
Day 8⃣of #50daysofDBMS
Started SQL ->
-> Creating Tables
->Providing Integrity Constraint: (not null, keys)
Update Table:
->insert, delete, drop table, alter table
Basic Query Structure
select An ( ,-,*,/)
from Rn
where P (or not and)
Keywords: distinct, all, as.
4
2 Dec 2021
Day 6⃣of #50daysofDBMS
Relational DB:
->Attribute types and domain
->Relation Schema and Instance
->Keys:Super,Candidate,Primary,Surrogate,Alternate,
Simple,Composite,Foreign,Compound.
->Declarative programming.
->Operations:Select,Project,Union,-,X,composite.
->NoSQL vs SQL
5
27 Nov 2021
Day5⃣of #50daysofDBMS
->Transcation management,Concurrency control manager.
->Database Users and Administrators
->Database internals and its Architecture.
->Architecture of DB also depends on Computer System on which it is running.(Centralised,Distributed,clientserver,Parallel)
4
27 Nov 2021
Day4⃣of #50daysofDBMS(26/Nov)
->Design Methodology (ER Model Normalisation)
->Overview of Object Relational Model and use XML
in data interchange formats.
->Database Engine(Storage manager query processor {Parsing,translation,optimisation,evaluation})
5