SQL Basics — Part I

Definition: SQL (Structured Query Language, pronounced as “sequel”, or “S-Q-L”) is a programming language used to query, analyze, and manipulate data from databases.

Basics

• CREATE TABLE creates a new table.
• INSERT INTO adds a new row to a table.
• SELECT queries data from a table.
• UPDATE edits a row in a table.
• DELETE FROM deletes rows from a table.
• ALTER TABLE changes an existing table. In other words add something to a table.

Let’s dive deeper into each of their syntax.

Create a table

CREATE TABLE table_name (
    column1 datatype,
    column2 datatype,
    column3 datatype
);

Insert into a table

INSERT INTO table_name (column1, column2, column3)
VALUES (value1, 'value2', value3);

Select

SELECT column_name FROM table_name;
// OR
SELECT * FROM table_name;  -- For all fields in the table

Update

UPDATE table_name 
SET column1 = value1
WHERE some_column = some_value;

Delete

DELETE FROM table_name 
WHERE column1 = value1;

Alter a table

ALTER TABLE table_name 
ADD column_name datatype;

Thank you for reading!

Next up is more about writing queries in SQL…