SQL

Create A SQL Database

So you’re ready to write some software? Or test some cool stuff. Or build something awesome. You can use the CREATE DATABASE statement to get started, by creating a database. To do so is pretty easy, simply run that statement followed by a name for the database (called Customers):

CREATE DATABASE Customers;

Once you’ve created a database, it’s time to create tables, which can be done using the CREATE TABLE statement. The Syntax of that statement looks something like this, defining a set of columns, their data type and the size of the column (in the form of a maximum length), all wrapped in parenthesis with each column separated by a comma:

CREATE TABLE nameoftable
(
column datatype(size),
column datatype(size),
);

So to create the Customers table that we’ve been using through these articles, we’ll use the following SQL Statement:

CREATE TABLE Customers
(
ID integer(255),
Site varchar(255),
Contact varchar(255),
Address varchar(255),
City varchar(255),
Zip integer(255),
Country varchar(255),
);

Columns are created with data types. In the previous example, we named columns of integers and varchars. The available data types include the following:

  • CHARACTER: A string of characters using a defined length
  • VARCHAR: A variable length string of characters using a maximum length
  • BINARY: A binary string
  • BOOLEAN: TRUE or FALSE
  • VARBINARY: Binary string in a variable length, with a defined maximum length
  • INTEGER: A number with no decimals
  • SMALLINT: A 5 digit or less number with no decimals
  • BIGINT: A 19 digit or less number with no decimals
  • DECIMAL: Number with decimals
  • FLOAT: Floating number in base 10
  • REAL: Number
  • DOUBLEPRECISION: Approximate number
  • DATE: Year, month, and day in separated values
  • TIME: Hour, minute, and second in separated values
  • TIMESTAMP: Time in the form of year, month, day, hour, minute, and second
  • INTERVAL: A period of time
  • ARRAY: Ordered collection of data
  • MULTISITE: Unordered collection of data
  • XML: Stores XML