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@ -582,7 +582,6 @@
M. A Khan Secretary M. A Khan Secretary
``` ```
- DONE memo report - DONE memo report
- Format - Format
- Abstract - Abstract
@ -874,46 +873,46 @@
- LATER Block 1 - LATER Block 1
- DONE DBMS - DONE DBMS
- Database is :-> a shared collection of logically related data (and a description of this data), designed to meet the information needs of an organization. - Database is :-> a shared collection of logically related data (and a description of this data), designed to meet the information needs of an organization.
id:: 64895ec0-d724-4159-a95d-657afd171c29 id:: 648974ba-3221-48b2-8f9c-2d9275174f48
- Table :-> A collection of related data organized into rows (also called records) and columns (also called fields). - Table :-> A collection of related data organized into rows (also called records) and columns (also called fields).
id:: 64895ec0-2290-4f62-8711-45e99803c82e id:: 648974ba-7b5a-4cff-8d21-3bcc7e0c1fe8
- Row/Record :-> A single set of data in a table, representing a specific instance or entity. - Row/Record :-> A single set of data in a table, representing a specific instance or entity.
id:: 64895ec0-12a9-402d-8c1d-64c40e169bb2 id:: 648974ba-d192-4027-945a-9c6113ac218f
- Column/Field :-> A specific attribute or data element within a table. - Column/Field :-> A specific attribute or data element within a table.
id:: 64895ec0-2aed-4aa8-a34f-446fd7715db6 id:: 648974ba-89e7-434a-b242-68a1ea3f7f6b
- Primary Key :-> A unique identifier for each row/record in a table. It ensures the integrity and uniqueness of the data. - Primary Key :-> A unique identifier for each row/record in a table. It ensures the integrity and uniqueness of the data.
id:: 64895ec0-7339-477c-b765-b12fd18e9df4 id:: 648974ba-611e-4d5c-849b-9cd57b7bddb9
- Foreign Key :-> A field in one table that refers to the primary key in another table, establishing a relationship between the two tables. - Foreign Key :-> A field in one table that refers to the primary key in another table, establishing a relationship between the two tables.
id:: 64895ec0-75e5-4378-aa9c-b4af6d7d37c9 id:: 648974ba-bc0d-4b78-a8cb-7a081ca1b2ac
- Relationship :-> The connection between tables based on common data values, such as primary and foreign keys. - Relationship :-> The connection between tables based on common data values, such as primary and foreign keys.
id:: 64895ec0-ab80-4eed-bb91-0911b1954368 id:: 648974ba-851d-42a7-95c1-2619fed22d3a
- Normalization :-> The process of organizing and structuring a database design to eliminate redundancy and improve data integrity. - Normalization :-> The process of organizing and structuring a database design to eliminate redundancy and improve data integrity.
id:: 64895ec0-8b79-4172-8cad-25e4edada659 id:: 648974ba-53b0-4176-b67b-cd51d1ea09c6
- Index :-> A data structure that improves the retrieval speed of data from a database table by creating a quick reference to the location of the data. - Index :-> A data structure that improves the retrieval speed of data from a database table by creating a quick reference to the location of the data.
id:: 64895ec0-f3cd-4625-b2ca-6e94f870b34d id:: 648974ba-2246-42c3-aa0c-7609107af7c5
- Query :-> A request for data or information from a database, usually written using Structured Query Language (SQL). - Query :-> A request for data or information from a database, usually written using Structured Query Language (SQL).
id:: 64895ec0-df79-46a4-8fb2-09b34a414c9c id:: 648974ba-4b3e-4f99-90fd-b4c9a1a43a53
- SQL (Structured Query Language) :-> A programming language used to manage and manipulate relational databases. It allows you to create, modify, and retrieve data from databases. - SQL (Structured Query Language) :-> A programming language used to manage and manipulate relational databases. It allows you to create, modify, and retrieve data from databases.
id:: 64895ec0-4de4-4cfd-8042-7f92458a8a26 id:: 648974ba-a844-4e21-a1ca-e0b26668f1b7
- CRUD Operations :-> An acronym for Create, Read, Update, and Delete operations, which are the basic operations used to manage data in a database. - CRUD Operations :-> An acronym for Create, Read, Update, and Delete operations, which are the basic operations used to manage data in a database.
id:: 64895ec0-77ed-4253-947e-2a54c4235a05 id:: 648974ba-34d4-49df-91c9-b44b018120c6
- ACID (Atomicity, Consistency, Isolation, Durability) :-> A set of properties that guarantee the reliability and integrity of database transactions. - ACID (Atomicity, Consistency, Isolation, Durability) :-> A set of properties that guarantee the reliability and integrity of database transactions.
id:: 64895ec0-e18b-4340-8a24-98b2cbaec1fd id:: 648974ba-4174-45b7-8903-38ffea39a200
- Data Integrity :-> The accuracy, consistency, and reliability of data stored in a database. - Data Integrity :-> The accuracy, consistency, and reliability of data stored in a database.
id:: 64895ec0-023b-47dc-96bd-7a4c52fd9717 id:: 648974ba-7797-4a43-b644-f0780da5121b
- Database Schema :-> The structure or blueprint of a database, defining the tables, fields, relationships, and constraints. - Database Schema :-> The structure or blueprint of a database, defining the tables, fields, relationships, and constraints.
id:: 64895ec0-0c9b-49fc-923d-264841105690 id:: 648974ba-7b5c-45d1-ac86-ef7211c9672a
- Database Management System (DBMS) :-> Software that provides an interface to interact with databases, managing their creation, modification, and retrieval. - Database Management System (DBMS) :-> Software that provides an interface to interact with databases, managing their creation, modification, and retrieval.
id:: 64895ec0-60c1-468f-bc13-bd65c736a682 id:: 648974ba-627d-463c-9237-56777d45b8af
- DONE basic concepts of Relational model - DONE basic concepts of Relational model
- A data model :- > a graphical description of the - A data model :- > a graphical description of the
components of database. components of database.
- A relation, is :-> a two-dimensional table arranged in columns and rows. - A relation, is :-> a two-dimensional table arranged in columns and rows.
id:: 64895ec0-a8ef-4e61-8e31-ce2b319a459b id:: 648974ba-40ec-4600-af39-d438a5f75339
- A relational database is :-> a collection of relations. - A relational database is :-> a collection of relations.
id:: 64895ec0-4f99-4abd-a0f1-a0707ff20bd7 id:: 648974ba-c76d-4f2b-a8ad-ef1ad3a16b2c
- Candidate Key #flashcard - Candidate Key #flashcard
id:: 64895ec0-44d2-4816-9201-492149a1e26e id:: 648974ba-a2f3-43a1-a5ea-c170c68314e1
- A set of attributes that uniquely identifies a tuple within a - A set of attributes that uniquely identifies a tuple within a
relation. relation.
- Uniqueness : In each tuple, candidate key uniquely identify - Uniqueness : In each tuple, candidate key uniquely identify
@ -921,36 +920,36 @@
- Irreducibility: No proper subset of the candidate key has the - Irreducibility: No proper subset of the candidate key has the
uniqueness property. uniqueness property.
- Primary Key #flashcard - Primary Key #flashcard
id:: 64895ec0-057c-49f6-8fd9-0fc599e49e0a id:: 648974ba-c5dc-44cb-8894-8f5838714f2a
- Candidate key selected to identify tuples uniquely within - Candidate key selected to identify tuples uniquely within
relation. relation.
- Foreign Key #flashcard - Foreign Key #flashcard
id:: 64895ec0-2bf4-4bf5-92f3-b266cfcce167 id:: 648974ba-da05-48b6-aded-75d1ea5f1342
- Attribute, or set of attributes, within one relation that - Attribute, or set of attributes, within one relation that
matches candidate key of some (possibly same) relation. matches candidate key of some (possibly same) relation.
- Composite Key #flashcard - Composite Key #flashcard
id:: 64895ec0-7b2e-4031-97ca-157c1864ac1c id:: 648974ba-7242-4c00-b67b-5418c3f71e77
- A candidate key that consists of two or more attributes. - A candidate key that consists of two or more attributes.
- Recursive Relationship #flashcard - Recursive Relationship #flashcard
id:: 64895ec0-96f6-4a17-8d67-ddd8c7679066 id:: 648974ba-eb07-4e80-a1c3-87555fb04d1a
- Relationship type where same entity type participates - Relationship type where same entity type participates
more than once in different roles. more than once in different roles.
- Multiplicity :-> number (or range) of possible - Multiplicity :-> number (or range) of possible
id:: 64895ec0-3514-4e82-acf6-f25238116bb7 id:: 648974ba-5d96-4c64-a1b0-e9e61aa3563a
occurrences of an entity type that may relate to a occurrences of an entity type that may relate to a
single occurrence of an associated entity type single occurrence of an associated entity type
through a particular relationship. through a particular relationship.
![image.png](../assets/image_1686723218703_0.png) ![image.png](../assets/image_1686723218703_0.png)
- Cardinality #flashcard - Cardinality #flashcard
id:: 64895ec0-4ad7-43f2-80fc-489bc0a07ec1 id:: 648974ba-b24d-40a3-8669-9dbc85dedaf7
- Describes {{c1 maximum}} number of possible relationship occurrences for an entity participating in a given relationship type. - Describes {{c1 maximum}} number of possible relationship occurrences for an entity participating in a given relationship type.
id:: 64895ec0-e8d2-47e1-97b8-d81ed8d62f64 id:: 648974ba-ea33-489d-bb7b-1951685babd0
- Participation #flashcard - Participation #flashcard
id:: 64895ec0-c4c3-400e-9cb6-08f722328773 id:: 648974ba-6dc5-4805-9dfd-7db5a83efe3f
- Determines whether all or only some entity occurrences participate in a relationship. - Determines whether all or only some entity occurrences participate in a relationship.
- Gives the minimum number for an entity occurrences participating in a given relationship type. - Gives the minimum number for an entity occurrences participating in a given relationship type.
- Ternary relationship #flashcard - Ternary relationship #flashcard
id:: 64895ec0-0897-4857-b763-0349ae186d62 id:: 648974ba-9b7a-4543-b243-e7a78cfc8175
- a ternary relationship is not the same as three binary relationships! - a ternary relationship is not the same as three binary relationships!
- LATER basic concepts associated with Entity-Relationship(ER) model. - LATER basic concepts associated with Entity-Relationship(ER) model.
- LATER Forming sql queries - LATER Forming sql queries
@ -1215,4 +1214,4 @@
SCHEDULED: <2023-06-19 Mon> SCHEDULED: <2023-06-19 Mon>
- {{embed ((647bf024-41f1-45e7-afaf-f49026e826d6))}} - {{embed ((647bf024-41f1-45e7-afaf-f49026e826d6))}}
- ![2023-06-09-13-21-19.jpeg](../assets/2023-06-09-13-21-19.jpeg) - ![2023-06-09-13-21-19.jpeg](../assets/2023-06-09-13-21-19.jpeg)
- -