Databases

 Databases..

1. Create Database :

• A database is used to store the collection of records in an organized form. 
• It allows us to hold the data into tables, rows, columns, and indexes to find the relevant information frequently. 
• We can access and manage the records through the database very easily.

Syntax :

CREATE DATABASE mydb;

2. Drop Database : 

• The DROP DATABASE statement is used to drop an existing SQL database.

Syntax :

DROP DATABASE databasename;

3. Select Database : 

• Select Database use to select particular database which available in Databases.

Syntax :

USE databasename;

4. Show Database : 

• Show Database use to show list of all databases which available in Databases.

Syntax :

SHOW databasename;

Tables in Mysql  

1. Create Table : 

• The CREATE TABLE statement is used to create a new table in a database.

Syntax :

CREATE TABLE table_name (

    column1 datatype,

);

2. Drop Table : 

• The DROP TABLE statement is used to drop an existing table in a database.

Syntax :

DROP TABLE table_name;

3. Truncate Table : 

• The TRUNCATE TABLE statement is used to delete the data inside a table, but not the table itself.

Syntax :

TRUNCATE TABLE table_name;

4. Alter table Statement : 

• The ALTER TABLE statement is used to add, delete, or modify columns in an existing table.
• The ALTER TABLE statement is also used to add and drop various constraints on an existing table.

• Add column :

Ex :

ALTER TABLE Customers

ADD Email varchar(255);

• Drop Column :

Ex :

ALTER TABLE Customers

DROP COLUMN Email;