Databases and tables
SQL can execute a query against a database, retrieve information from a database, insert new information into a database, remove old information from a database, update current information, create new databases and more.
The next step is to create a database.
Creating a database
The first thing that this tutorial is going to focus on is creation of databases.
A database is a collection of items, in the case of SQL, tables .
A database may consist of many tables. A table consists of records and fields .
The very first thing to do when working with MySQL after connecting successful is to create a database. This is done with the syntax as below:
CREATE DATABASE my_db
This will create a new database with the name
Creating a table
Creating a table is not much different, except that fields need to be added when it is created.
A table is created in the same way with brackets following which contain the names of the fields:
CREATE TABLE People ( ID INT, Name VARCHAR(255), Address VARCHAR(255), Phone VARCHAR(255) )
In this example, there are four fields:
|Field name||Field type|
It's common when creating a table to use multiple lines for a single query with each row on a new line and the closing bracket on a new line.
Getting a list of all databases and tables
Getting a list of all of the databases and tables is done using the
SHOW DATABASES SHOW TABLES
Deleting (dropping) a database or table
Deleting a database or table is called
it. It uses the
keyword to do precisely this.
DROP TABLE mydb.mytable DROP DATABASE mydb