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Showing posts from July, 2021

Database

  9/7 ## Database - Organized collection of structured information or data. - Database is a collection of entity(also called as table). - Entity is a collection of records. ## Types of database 1) Local database (installed in PC) 2) Web database  (host, server side) ## Python support database 1) MySQL 2) Microsoft SQL server 3) Mongo DB 4) SQL lite  ## Database Library  1) PySQL 2) PyMongo ## Database Terminology 1) field-represent the record ex. name,age,etc. ## Types of fields 1) Single value field - accept only one value at a time  ex. aadhaar card, pancard 2) Multi-value field- ex.name(firstname, lastname), country(city,state) 3) Null value field(blank) ex. mobile no. ## Tuple - complete info is called tuple roll     name      city  1           A         ngp 2           B        delhi 3          ...