SQL

1. Statements

1.1. DDL

1.1.1. Create

1.1.2. Alter

1.1.3. Drop

1.2. DML

1.2.1. Insert

1.2.2. Update

1.2.3. Delete

1.2.4. Select

2. Key Constraints

2.1. Primary Key

2.2. Foreign Key

2.3. Unique Key

3. Aggregate functions

3.1. COUNT

3.2. MIN

3.2.1. with integers

3.2.1.1. lowest value

3.2.2. with varchar

3.2.2.1. first value (alphabetically - A to Z)

3.3. MAX

3.3.1. with integers

3.3.1.1. largest value

3.3.2. with varchar

3.3.2.1. last value (alphabetically - Z to A)

3.4. AVG

3.4.1. used with numbers only!

3.5. SUM

3.5.1. used with numbers only!

4. Data Types

4.1. Integer

4.2. Varchar

4.3. Datetime

5. Clauses

5.1. Where

5.1.1. filters rows based on a condition

5.2. Having

5.2.1. filters groups based on a condition

5.3. Order by

5.3.1. sorts records based on specified columns

5.4. Group by

5.4.1. arranges similar data into groups (based on specified criteria)