Sq lite module6

MODULE 6: SQLITE AND THE STUNES
DATABASE
SQL and Scripting Training
(C) 2020-2021 Highervista, LLC 1

2
TOPICS
Next Steps with SQLite and DBBrowser
Launching the DBBrowser software
Open the sTunes Database
Exploring the sTunes Database
The Browse Data tab
The Execute tab
Getting started with SQLite queries
Notation techniques for queries
SQL query basics
Using an alias
Sorting results alphabetically
Limiting query results
Operators in SQL
The WHERE clause
Searching for text using wildcard values
The DATE ( ) function
Using OR and AND together
The CASE Statement
Summary

NEXT STEPS WITH SQLITE AND
DB BROWSER
SQL and Scripting
Training

4
SQLITE CLI AND DB BROWSER GUI: WHAT
WE′LL DO
Examine an existing database to get familiar with the SELECT commands
in order to Report and View the database (sTunes database)
Use a browser tool—DB Browser for SQLite
Explore several database query and view items using DB Browser and a
preconfigured sTunes Database
After using the GUI, return to the use of the command line CLI to
Create a database in SQLite CLI
Create a new database, create and load several tables, and enter code into the
CLI.
Briefly discuss how to use Python with SQLite

LAUNCHING THE DB BROWSER
SOFTWARE
SQL and Scripting
Training

6
MOVE THE STUNES DATABASE
Move the sTunes database to a location on your computer where
you can easily locate it.
The sTunes database is available in the SQL course resources.

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FROM A BROWSER, LAUNCH THE DB
BROWSER

OPEN THE STUNES DATABASE
SQL and Scripting
Training

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WITH THE DB BROWSER OPEN, CLICK OPEN
DATABASE

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FROM THE DIALOG BOX, SELECT THE STUNES
DB

EXPLORING THE STUNES
DATABASE
SQL and Scripting
Training

12
STUNES EXAMPLE DATABASE
Located in student resources (place in a folder like SQL Class)
Open DB Browser for SQLite

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STUNES DATABASE—INTENTION
Intention and scope:
Online retail music sales data
Contains product information (songs and albums), personal customer
information, employee records, and sales data.
Tasks will be to analyze the database and discover insights about
the data using SQL commands.
Explore the sTunes Database

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USING THE STUNES DATABASE
Think in terms of natural language questions. Example:
Instead of
How many entries are in the customer table?
Think
How many customers do we have?

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EXAMINE THE DATABASE STRUCTURE
WINDOW
13 tables
Fields: Expand the arrow to the left of the
table names.

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TABLES (13) AND FIELDS IN THE ALBUMS TABLE
What are the data types?
What is a database record?

THE BROWSE DATA TAB AWS SQL and Scripting Training

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VIEWING INDIVIDUAL RECORDS
Browse Data tab can be used to see
the records contained in each table.
Example: Albums table
In row 1:
o AlbumID = 1
o Title = For Those About to Rock We
Salute You
o ArtistId = 1
Note: ArtistId is a FK

THE EXECUTE TAB SQL and Scripting
Training

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EXECUTE SQL TAB
The Execute SQL Tab is where you write your SQL statements
(instead of writing SQL in a CLI, you are writing SQL in a window
or GUI)
Three main window components:
Query pane
Results pane
Messages pane

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EXECUTE SQL TAB
SQL code entered:
SELECT
*
FROM
albums;

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EXECUTE SQL TAB Results (below) include:
Number of rows returned
How much time the query
took to run
Error messages?
Entry screen below:

SQLITE QUERIES: GETTING
STARTED
SQL and Scripting
Training

26
NOTATION TECHNIQUES FOR QUERIES:
COMMENTS
Comments are not processed by the SQL
engine.
Helps and provides insight into the SQL
(especially important in maintenance)
Industry best practice
Comments: -- for a line comment or /*
*/ for a comment ‘block’

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EXAMPLE SQL QUERY (COMMANDS)
select burger
from kitchen
where patties=2
and toppings=‘jalopenos’
and condiment != ‘mayo’
limit 1;

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REVIEW: TYPES OF QUERIES
DDL (Data Definition Language): Used to create tables
create [temp] table table_name (column_definitions [,
constraints]);
DML (Data Manipulation Language): Used to insert data, modify, data
and/or update data in a database
select …

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THE STRUCTURE OF A BASIC QUERY
A query is like asking a question in a natural
language.
The order of words matters.
1.What database?
2.What table(s) within a database are we requesting information
from?
3.What fields are we interested in?
4.What do we want to exclude, filter, or omit? (a range of time, for
example)
5.In one concise sentence, what does the query do?
Questions when writing a query:

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WRITING THE QUERY
Write directly into the Query pane or ...
Write in a text editor (now a word processor) to save it.

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WRITING THE QUERY
Open the Query pane.
Identify who wrote it, a date,
and a description.

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THE STRUCTURE OF A BASIC QUERY
/*
Created by: Ron McFarland
Created on: October 5, 2020
Description: This query selects the first name, last name, and email from the
Customers table on the sTunes database.
*/
SELECT
FirstName,
LastName,
Email
FROM
customers;

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RESULTS
Messages Pane: 59 rows
in 3 milliseconds
Note: Writing SQL in a
consistent way is known
as coding standards.

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CODING SYNTAX VS. CODING
CONVENTION
All queries must conform with SQL syntax in order to be understood by the
SQL engine.
Coding convention varies based on the database environment.
Some conventions:
The * (asterisk) in the SELECT * means ″all.″ Some engines allow SELECT ALL (use * in SQLite).
The ; (semi-colon) at the end of a single line in SQLite is optional for some database engines.
When selecting fields in the SELECT clause, use a comma ( , ) between field names (except
the last one):
SELECT name, address, phone_number from xxx;
Use this notation in SQLite, yet other engines may not require the comma (,).

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CODING SYNTAX VS. CODING
CONVENTION
SQLite uses the SQL-92 standard, core to modern
RDBMS tools.
Some RDBMS tools go beyond SQL-92 standards.
SQL-92 is a major subset of several RDBMS products.
SQL-92 standard
Other RDBMS tools
(probable) extensions

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ALIAS
An alias allows you to provide an alternate name to a
display/report.
For example, an alias may be used if the table field name does
not reflect the field name the user would like to see on a report
or screen.

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ALIAS/*
Created by: Ron McFarland
Created on: 10/5/2020
Description: This query selects the first name, last name, email, and
phone number fields from the customers table and shows 4 different
ways to report/display the field information.
*/
SELECT
FirstName AS ‘First Name’,
LastName AS [Last Name],
Email AS EMAIL,
Phone CELL
FROM
customers;
Note: For most RDBMS tools, the
alias notation will work fine.
However, if you get an error on an
alias using another RDBMS tool,
double check the documentation
pertaining to alias.

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FIELD NAMES WITH/WITHOUT ALIAS
Without Alias With Alias

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SORTING: USING THE ORDER BY
Scenario: In the sTunes database, the customer service department may want a list of
customers sorted by customer last name.
The ORDER BY clause provides the option to sort based on the fields chosen.
The default sort order in the ORDER BY clause is in descending order. You could add
the DESC keyword if desired.
To sort in ascending order, use the ASC keyword with the ORDER BY clause.

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ORDER BY. ASC RESULTS
Note: Without the ORDER BY
clause, every query will return
data in the order that it was
initially saved in the table (FIFO).
SELECT
FirstName AS 'First Name',
LastName AS [Last Name],
Email AS EMAIL
FROM
customers
ORDER BY
LastName ASC

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SORTING ON MULTIPLE FIELDS
You can sort on multiple fields to create output that meets the user′s
requirements.
Sorting is in order of the field names.
Both ASC and DESC can be used in a sort.

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ORDER BY WITH MULTIPLE FIELDS (ASC AND
DESC KEYWORDS)
Note: If you use the ORDER BY
statement on a column where
some of the corresponding rows
have empty values, these values
will show as NULL at the top if
you are using ASC order.

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LIMITING QUERY RESULTS: LIMIT KEYWORD
You can limit results to a specified number of rows using the LIMIT
keyword.
The LIMIT keyword is useful in testing scenarios or, for example, when
you are creating a query to look for the top values (e.g., highest sales).

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LIMIT—CHECK YOUR
MESSAGES

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COMPARISON, LOGICAL, AND
ARITHMETIC OPERATORS IN SQL
• Operators are special keywords used
with SQL clauses to compare the
values of fields, select subsets of
fields, or perform operators.
• Operators cannot exist as their own
SQL clause. They must be used with
other clauses like SELECT and
WHERE.
• These different types of operators can
be combined to make more complex
queries.

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ARITHMETIC OPERATORS USED WITH A
SELECT CLAUSE
SELECT
Total AS [Original Amount],
Total + 10 AS [Addition Operator],
Total – 10 AS [Subtraction Operator],
Total / 10 AS [Division Operator],
Total * 10 AS [Multiplication Operator],
Total % 10 AS [Modulus Operator]
FROM
invoices
ORDER BY
Total DESC

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FILTERING RECORDS BY NUMBERS WITHIN
THE WHERE CLAUSE
The WHERE operator clause will be encountered often.
WHERE limits the results of queries so that only data
satisfying the query is displayed.
1.Numbers
2.Text
3.Dates
Common types of data that can be filtered:

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USING THE WHERE CLAUSE
On sTunes, how many customers
purchased just two $.0.99
songs? One way to find out is
by looking in the invoices table
for amounts of $1.98, which
would probably represent two
songs.

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WHERE CLAUSE
Note: The WHERE Clause always
comes after FROM but before
ORDER BY.

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LOGICAL OPERATORS
Logical operators can help you
write more complex and
specific queries.
For example, if you were
asked to find out how many
invoices existed within a range,
such as $1.98 to $5.00.

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LOGICAL OPERATORS
Note: Using comparison operators, you could
write:
Total >= 1.98 AND Total <= 5.00
SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
WHERE
Total BETWEEN 1.98 AND 5.00
ORDER BY
InvoiceDate

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THE IN OPERATOR
IN is used to find a list of
precise values.
Note: BETWEEN is a range,
while IN is specific.

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THE IN OPERATOR
Note: With the = operator, we can find only one
value.
With the IN operator, we can add as many values,
separated by commas, as we need.
SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
WHERE
Total IN (1.98, 3.96)
ORDER BY
InvoiceDate

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FILTERING RECORDS BY TEXT
You can search for a specific text string
using the WHERE clause and looking for
a specific value of a field.
The values specified must be surrounded
by single quotes for text fields.

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RESULTS—ONLY TUCSON SHOWS

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FILTERING RECORDS BY TEXT: USING THE
IN CLAUSE
SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
WHERE
BillingCity IN ('Tucson', 'Paris', 'London')
ORDER BY
InvoiceDate

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SEARCHING FOR STRINGS: USING LIKE
TO SEARCH FOR WILDCARDS
Previously, we used the = operator to search for the exact text.
LIKE is useful when you are not sure how a text value is spelled in the
database.
LIKE operators can use wildcards to indicate variability for a given text
item.
The wildcard character is %.
For example: LIKE ′T%; will return any cities that start with T

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LIKE EXAMPLE
USING A WILDCARD

60
LIKE
EXAMPLE
USING A
WILDCARD
(LIKE T
ANYWHERE)

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LIKE EXAMPLE: WILDCARD USAGE

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DATE( ) FUNCTION: FILTERING RECORDS
EXAMPLE
Note: Look at the format of the date. Keep in mind
that the comparison format (the item to the right) must
be the same format as the field (left side).
You may need to look at the data dictionary or the
field description to verify the field format.
Dates are enclosed in single quotes, just as text fields
are.

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USING THE DATE( ) FUNCTION
SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
WHERE
DATE (InvoiceDate) = ‘2009-01-03’
ORDER BY
Total
Note: The result is identical to the
previous DATE query. However, it can be
more precise by feeding the comparison
value (on the right-hand side) into the
query as a parameter.

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USING THE AND OPERATORS WITH TWO
SEPARATE FIELDSSELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
WHERE
DATE (InvoiceDate) > ‘2010-01-02’ AND
Total < 3
ORDER BY
Total
Note: AND means both conditions must be true.
You can add more AND operators. You are
not limited to two values.

65
USING THE OR OPERATORS WITH TWO
SEPARATE FIELDSSELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
WHERE
BillingCity LIKE ‘p%’ OR BillingCity LIKE
‘d%’
ORDER BY
Total
Note: OR means only one condition must be true.

66
USING PARENTHESES WITH AND/OR TO
SPECIFY THE ORDER OF OPERATIONS
Note: As written, SQL processes the two conditions on either side of the
AND condition first (Total > 1.98 AND City begins with a P). Then the
OR condition is applied (City begins with a D). Results are returned for
BOTH conditions on both sides of the OR in ascending order. This may
not be the result you want!

67
Again, SQL processes the AND operator first (like
multiplication) and the OR operator next (like
addition), unless you use parentheses.
Without parenthesis, the AND will be processed in
the same way that 3*2+1 = 7. But with
parenthesis, 3*(2+1) = 9.

68
Note: The results shows invoices > than $1.98 from both cities that
start with a P or a D.
A best practice is to use parenthesis to clearly identify how you want
the query to execute.

69
THE CASE STATEMENT
The CASE statement allows you to create a new, temporary field in your database
that serves as a label for your data, based on unique user-specified conditions.
For example:
The sTunes sales team would like sTunes customers to spend $7 to $15 in the online store. They
have created categories: Baseline Purchase, Low Purchase, Target Purchase, and Top Performer.
Since the cost of a song varies from $0.99 to $1.99
Any invoice in this range is a Baseline Purchase.
$2.00 to $6.99 is a Low Purchase.
$7.00 to $15.00 is a Target Purchase.
Above $15.00 is a Top Performer.

70
THE CASE STATEMENT
The CASE statement is used to create a new field in the invoices table.
Let’s call the new field PurchaseType. This new field will appear
alongside the other pre-existing fields in our query, as if it were another
field in the database.

71
CODING THE CASE STATEMENT: STEP 1
Start with a SELECT statement with
the pre-existing database fields of
interest from the invoices table.
For this example, let’s use sales
totals by city.
SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total
FROM
invoices
ORDER BY
BillingCity

72
To add the CASE statement to the query,
place it at the bottom of the SELECT portion
of the query after the existing fields.
Start by adding the keyword CASE followed
by the END keyword.
Each test begins with the keyword WHEN.
The ELSE keyword is the last explicit
condition listed (ELSE is optional and if not
used, fields not identified by the WHEN are
ignored).
SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total,
CASE
…
END
FROM
invoices
ORDER BY
BillingCity

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SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total,
CASE
WHEN TOTAL < 2.00 THEN ‘Baseline Purchase’
WHEN TOTAL BETWEEN 2.00 AND 6.99 THEN ‘Low Purchase’
WHEN TOTAL BETWEEN 7.00 AND 15.00 THEN ‘Target
Purchase’
ELSE ‘Top Performers’
END AS PurchaseType
FROM
invoices
ORDER BY
BillingCity

74
CASE STATEMENT APPLIED TO THE
STUNES DB
Note: Use the ORDER BY
to order results, perhaps in
the new PurchaseType
field.

75
USING THE NEW FIELD: PURCHASETYPE
Additional questions using PurchaseType:
What cities do the top-performing sales come from?
Are the top-performing sales mainly from the US or are they from other
parts of the world?
From what cities are the most baseline purchase made?
And others …

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SELECT
InvoiceDate,
BillingAddress,
BillingCity,
Total,
CASE
WHEN TOTAL < 2.00 THEN ‘Baseline Purchase’
WHEN TOTAL BETWEEN 2.00 AND 6.99 THEN ‘Low
Purchase’
WHEN TOTAL BETWEEN 7.00 AND 15.00 THEN ‘Target
Purchase’
ELSE ‘Top Performers’
END AS PurchaseType
FROM
invoices
WHERE PurchaseType = ’Top Performers’
ORDER BY
BillingCity
USING THE NEW FIELD:
PURCHASETYPE = ′TOP
PERFORMERS′

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RESULTS: PURCHASETYPE = ′TOP
PERFORMERS′

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SUMMARY
Adding comments to queries is considered a best practice.
When composing a query, it is useful to phrase what you want from the query in a natural language first, then
decide what keywords you need.
The basic query usually begins with a SELECT clause that specifies what fields to display from the table using
the FROM clause. (e.g., SELECT … FROM …).
An alias used after the AS keyword can rename the field names in your query results. The ALIAS does not
affect the data in the database nor does it modify the field metadata.
The ORDER BY clause allows you to sort alphabetically either in ASC (ascending) or DESC (descending) order.
The LIMIT keyword, which is used after the ORDER BY clause, will limit the number of records in the query
results (you must include the number of results you wish to show).

79
SUMMARY
Operators are special SQL keywords that are used with SQL clauses to filter data by specific
conditions.
Using the WHERE clause with a combination of different operators can enable the user to search
records for specific text, dates, and numbers.
The Date ( ) function allows us to exclude the timecode when specifying our date criteria.
The order of operations when using logical operators (such as AND/OR) can be controlled by
parentheses ( ).
The CASE statement allows you to label records with a special field name based on user-specified
logical conditions.

80
REFERENCES
Allen, G., & Owens, M. (2010). The definitive guide to SQLite.
Draw.io. (2020). Diagrams.net. Free flowchart maker and diagrams online. Retrieved
November 23, 2020, from https://app.diagrams.net/
Shields, W. (2019). Sql quickstart guide: the simplified beginner's guide to
managing, analyzing, and manipulating data with Sql. Clydebank Media.
SQLite Browser. (2020, November 09). DB Browser for SQLite. Retrieved November 23, 2020,
from https://sqlitebrowser.org/
SQLite. (2020). SQLite Main Website. Retrieved November 23, 2020, from
https://sqlite.org/index.html
Tutorialspoint. (2020). SQLite Tutorial. Retrieved November 23, 2020, from
https://www.tutorialspoint.com/sqlite/index.htm

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INTRODUCTION
Ron McFarland
Technologist, Educator
Source: Microsoft Images

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ABOUT THIS COURSE
This course is distributed free. I use several
sources. But importantly, I use the book noted
on the next slide.
If you are using these PowerPoints, please
attribute Highervista, LLC and me (Ron
McFarland). IN ADDITION, please attribute
the author noted on the next slide, as the
author’s textbook provides essential
information for this course.
Source: Microsoft Images

83
INTRODUCTION
This course is offered to you free. HOWEVER, please
purchase the following book, as it is a primary resource for
this course. I do not make any $ from this course or this
book. So, since a handful of good content is derived from the
following text, please support this author!
Title: SQL Quickstart Guide
Author: Walter Shields
Available: Amazon, B&N, and through ClydeBank media
website at:
https://www.clydebankmedia.com/books/programming-
tech/sql-quickstart-guide

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