1st Normal Form

PostgreSQL डेटाबेस बनाना

Darryl Reeves

Industry Assistant Professor, New York University

उदाहरण: छात्र रिकॉर्ड संभालना

CREATE TABLE student (
    id SERIAL PRIMARY KEY,
    name VARCHAR(50) NOT NULL,
    courses VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

अपडेट errors
इन्सर्शन errors
डिलीशन errors

उदाहरण: अपडेट के बाद डुप्लिकेटेड डेटा

id	name	courses	home_room
122	Susan Roth	Algebra I, Physics, Spanish II	101
413	Robert Cruz	History, Geometry, Biology	204
613	Thomas Wright	English III, Chemistry, Algebra II	102

उदाहरण: अपडेट के बाद डुप्लिकेटेड डेटा

id	name	courses	home_room
122	Susan Roth	Algebra I, Chemistry, Spanish II	101
413	Robert Cruz	History, Geometry, Biology	204
613	Thomas Wright	English III, Chemistry, Algebra II	102

उदाहरण: अपडेट के बाद डुप्लिकेटेड डेटा

id	name	courses	home_room
122	Susan Roth	Algebra I, Chemistry, Spanish II, Chemistry	101
413	Robert Cruz	History, Geometry, Biology	204
613	Thomas Wright	English III, Chemistry, Algebra II	102

उदाहरण: कॉलम प्रतिबंधों के साथ इन्सर्शन

CREATE TABLE student (
    id SERIAL PRIMARY KEY,
    name VARCHAR(50) NOT NULL,
    courses VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

id	name	courses	home_room
122	Susan Roth	Algebra I, Physics, Spanish II	101
413	Robert Cruz	History, Geometry, Biology	204
613	Thomas Wright	English III, Chemistry, Algebra II	102

उदाहरण: कॉलम प्रतिबंधों के साथ इन्सर्शन

CREATE TABLE student (
    id SERIAL PRIMARY KEY,
    name VARCHAR(50) NOT NULL,
    courses VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

id	name	courses	home_room
122	Susan Roth	Algebra I, Physics, Spanish II	101
413	Robert Cruz	History, Geometry, Biology, French Literature	204
613	Thomas Wright	English III, Chemistry, Algebra II	102

उदाहरण: रिकॉर्ड डिलीट करने से डेटा इंटीग्रिटी पर असर

id	name	courses	home_room
122	Susan Roth	Algebra I, Physics, Spanish II	101
413	Robert Cruz	History, Geometry, Biology	204
613	Thomas Wright	English III, Chemistry, Algebra II	102

उदाहरण: रिकॉर्ड डिलीट करने से डेटा इंटीग्रिटी पर असर

id	name	courses	home_room
122	Susan Roth	Algebra I, Physics, Spanish II	101
413	Robert Cruz	History, Geometry, Biology	204
613	Thomas Wright	???	102

1st Normal Form (1NF) पूरी करना

1NF आवश्यकता:
- टेबल वैल्यू atomic होनी चाहिए

उदाहरण: 1NF को संतुष्ट करती student टेबल

CREATE TABLE student (
    id SERIAL PRIMARY KEY,
    name VARCHAR(50) NOT NULL,
    courses VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

Example: student table satisfying 1NF

CREATE TABLE student (
    id INTEGER,
    name VARCHAR(50) NOT NULL,
    courses VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

Example: student table satisfying 1NF

CREATE TABLE student (
    id INTEGER,
    name VARCHAR(50) NOT NULL,
    course VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

Example: student table satisfying 1NF

id	name	course	home_room
122	Susan Roth	Algebra I	101
122	Susan Roth	Physics	101
122	Susan Roth	Spanish II	101
413	Robert Cruz	History	204
413	Robert Cruz	Geometry	204
413	Robert Cruz	Biology	204

Example: student table satisfying 1NF

CREATE TABLE student (
    id INTEGER,
    name VARCHAR(50) NOT NULL,
    course VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

Example: student table satisfying 1NF

CREATE TABLE student (
    student_id INTEGER,
    first_name VARCHAR(50) NOT NULL,
    last_name VARCHAR(50) NOT NULL,
    course VARCHAR(50) NOT NULL,
    home_room SMALLINT NOT NULL
);

Example: student table satisfying 1NF

id	first_name	last_name	course	home_room
122	Susan	Roth	Algebra I	101
122	Susan	Roth	Physics	101
122	Susan	Roth	Spanish II	101
413	Robert	Cruz	History	204
413	Robert	Cruz	Geometry	204
413	Robert	Cruz	Biology	204

Let's practice!

PostgreSQL डेटाबेस बनाना