MySQL

Calling Database

USE dataBaseName;

SELECT

SELECT - Identifies the column(s) you want your query to select for your results.

# Syntax
SELECT columnName

# Examples

# Return one or more specific columns in results by naming them
# Seperate column names with a comma
SELECT
    customer_id,
    rental_date
FROM rental;

SELECT DISTINCT

FROM

Comes after SELECT.

# Syntax
SELECT columnName 
FROM tableName

# Examples of SELECT and FROM

# Selects ALL columns from the specified table
# Without using a WHERE clause will return the entire table (all columns, all rows)
SELECT * 
FROM tableName

TIP - SELECT * FROM tableNameis a great way to quickly see what data a table contains.

WHERE

# Syntax
SELECT columnName 
FROM tableName 
WHERE logicalCondition

# Example
SELECT
	customer_id,
    rental_id,
    amount,
    payment_date
FROM payment
WHERE amount = 0.99

# Example 2
SELECT
	customer_id,
    rental_id,
    amount,
    payment_date
FROM payment
WHERE payment_date > '2006-01-01'

Comes after FROM.

WHERE Operators

WHERE Examples

WHERE & AND

WHERE & OR

WHERE & IN

LIKE

WILDCARD

GROUP BY

# Syntax
SELECT columnName 
FROM tableName 
WHERE logicalCondition 
GROUP BY columnName

Comes after WHERE.

AGGREGATE FUNCTIONS

HAVING

# Syntax
SELECT columnName 
FROM tableName 
WHERE logicalCondition 
GROUP BY columnName 
HAVING logicalCondition

Comes after GROUP BY and can only be used when GROUP BY is present.

ORDER BY

ORDER BY - (Optional) Specifies the order (sorting records) in which your query results are displayed. Comes last in query.

# Syntax
SELECT columnName 
FROM tableName 
WHERE logicalCondition 
GROUP BY columnName 
HAVING logicalCondition 
ORDER BY columnName

COMMENTS & ALIASES