Explore Library
Databases & SQLBasic SQL Queries (SELECT, WHERE, ORDER BY)

78 items

1

Filtering Rows With NULL Values

Code Quiz
2

SQL Clause Execution Order

Quiz
3

Filter Aggregates with HAVING

Code Quiz
4

Filtering and Sorting Results

Quiz
5

Core SQL Querying Essentials

Slides / Video
6

Filtering Aggregated Results

Quiz
7

SQL Query Building Blocks

Flashcard
8

Selecting All Columns With The Wildcard

Slides / Video
9

Removing Duplicates With DISTINCT

Quiz
10

Set Membership With IN

Quiz
11

Logical Order Of Clauses

Quiz
12

Selecting All Columns

Quiz
13

Selecting Specific Columns

Quiz
14

Column Aliases With AS

Quiz
15

Filtering With WHERE

Quiz
16

Comparison Operators

Quiz
17

Combining With AND / OR

Quiz
18

Negating With NOT

Quiz
19

Range Filtering With BETWEEN

Quiz
20

Pattern Matching With LIKE

Quiz
21

Filtering NULL Values

Quiz
22

Sorting With ORDER BY

Quiz
23

Ascending vs Descending Sort

Quiz
24

Sorting By Multiple Columns

Quiz
25

Limiting Result Rows

Quiz
26

String Literals And Quoting

Quiz
27

SQL Syntax Basics

Slides / Video
28

Limiting Rows With LIMIT and TOP

Slides / Video
29

Removing Duplicates With DISTINCT

Slides / Video
30

Sorting by Multiple Columns

Slides / Video
31

Ascending and Descending Order

Slides / Video
32

Sorting Results With ORDER BY

Slides / Video
33

Handling NULLs With IS NULL

Slides / Video
34

Set Membership Filtering With IN

Slides / Video
35

Range Filtering With BETWEEN

Slides / Video
36

Pattern Matching With LIKE

Slides / Video
37

Combining Conditions With AND, OR, NOT

Slides / Video
38

SQL Comparison Operators in WHERE

Slides / Video
39

Filtering Rows With WHERE

Slides / Video
40

Renaming Columns With AS Aliases

Slides / Video
41

Specifying Tables With FROM

Slides / Video
42

Limiting Returned Rows

Code Quiz
43

Sorting By Multiple Columns

Code Quiz
44

Clause Order In A Query

Code Quiz
45

Removing Duplicates With DISTINCT

Code Quiz
46

Selecting All Columns

Code Quiz
47

Selecting Specific Columns

Code Quiz
48

Column Aliases With AS

Code Quiz
49

WHERE Comparison Operator

Code Quiz
50

Combining Conditions

Code Quiz
51

Filtering Ranges With BETWEEN

Code Quiz
52

Filtering With IN

Code Quiz
53

Pattern Matching With LIKE

Code Quiz
54

Handling NULL Values

Code Quiz
55

Sorting With ORDER BY

Code Quiz
56

Sorting Descending

Code Quiz
57

Selecting Specific Columns by Name

Slides / Video
58

The SELECT Statement's Purpose

Slides / Video
59

WHERE Clause for Filtering

Flashcard
60

Selecting Specific Columns

Flashcard
61

Statement Termination with Semicolon

Flashcard
62

ORDER BY for Sorting

Flashcard
63

LIKE Operator and Wildcards

Flashcard
64

Logical Operators AND, OR, NOT

Flashcard
65

Column Aliases with AS

Flashcard
66

LIMIT Clause to Restrict Rows

Flashcard
67

Ascending vs Descending Sort

Flashcard
68

Filtering with IS NULL / IS NOT NULL

Flashcard
69

BETWEEN Operator for Ranges

Flashcard
70

Comparison Operators

Flashcard
71

SELECT DISTINCT for Unique Values

Flashcard
72

FROM Clause and Table Name

Flashcard
73

Selecting All Columns with *

Flashcard
74

SELECT Statement Basic Syntax

Flashcard
75

Case Sensitivity and Conventions

Flashcard
76

String Literals and Quoting

Flashcard
77

Sorting by Multiple Columns

Flashcard
78

IN Operator for Value Lists

Flashcard
Code QuizAdvanced

Filtering Rows With NULL Values

Spot why a WHERE clause comparing a column to NULL returns no rows.

Codesql
SELECT id, name, email
FROM users
WHERE email = NULL
ORDER BY name ASC;

This query should return users who have no email, but it returns zero rows. What is the bug?