This is a draft cheat sheet. It is a work in progress and is not finished yet.
Important Commands
SELECT - gets data from a database |
UPDATE - updates data in a database |
DELETE - deletes data from a database |
INSERT INTO - inserts new data into a database |
CREATE DATABASE - creates a new database |
ALTER DATABASE - modifies a database |
CREATE TABLE - creates a new column in a database |
ALTER TABLE - modifies a column |
DROP TABLE - deletes a table |
CREATE INDEX - creates an index (search key) |
DROP INDEX - deletes an index |
Statements
SELECT * FROM Customers; - select all records and fieldsin Customers |
SELECT column1, column 2, .... FROM table_name WHERE condition; |
SELECT DISTINCT column1, column2 ... FROM table_name; - returns different values |
SELECT COUNT(DISTINCT Country) FROM Customers; - lists number of different values |
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Operators
= Equal |
> Greater than |
< less than |
>= greater than or equal |
<= less than or equal |
<> Not eqal |
BETWEEN - between a certain range |
LIKE - search for a pattern |
IN - to specify multiple possible values for a column |
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