1. Chapter 4 6e & 8 5e: Basic SQL Prof. Steven A. Demurjian, Sr.
Computer Science & Engineering Department
The University of Connecticut
191 Auditorium Road, Box U-155
Storrs, CT
(860)
About one third of these slides are being used with the permission of Dr. Ling Lui, Associate Professor, College of Computing, Georgia Tech.
About one-half of these slides have been adapted from the AWL web site for the textbook.

2. Relational Languages A Relational Language
Defines Operations to Manipulate Relations
Used to Specify Retrieval Requests (Queries)
Query Result is Expressed in the Form of a Relation
Classification
Relational Algebra (We’ve Discussed)
Relational Calculus
To be Briefly Explored as the Basis of ...
Structured Query Language (SQL)
Relational calculus
non-procedural
state what the properties that should hold in the result relation are
Relational algebra
procedural
closed: use operators which work on one or two relations and produce another relation
chaining of operations

3. Relational Calculus Based on First-Order Predicate Logic
Symbol Alphabet
Logic Symbols (e.g., ¬
a Set of Constants
a Set of Variables
a Set of n-ary Predicates
a Set of n-ary Functions
Parentheses
Expressions (called well-formed formulae (wff)) Built from this Symbol Alphabet
Classification:
Tuple Relational Calculus
Domain Relational Calculus
Relational Calculus:
Instead of specifying how to obtain the result, specify what the result is, i.e., the relationships that is supposed to hold in the result.
Classification:
according to the primitive variable used in specifying the queries
tuple relational calculus
domain relational calculus

4. Tuple Relational Calculus
The Primitive Variable is a Tuple Variable Which
Specifies a Tuple of a Relation
Ranges Over the Tuples of a Relation
In Tuple Relational Calculus, Queries are Specified as {t | F(t)} where t is a Tuple Variable and F is a Formula Consisting of the Atoms and Operators

5. Example EMP(ENO, ENAME, AGE) PROJ(PNO, PNAME, LOC, MGR)
WORKS(ENO, PNO, DUR)
Find the Names of Employees under age 30
{ t[ENAME] | tEMP t[AGE]<30}
Find the Names of Employees working on the CAD/CAM Project
{ t[ENAME] | tEMP u(u WORKS t[ENO]u
v(vPROJu[PNO]=v[PNO] v[PNAME]=‘CAD/CAM’))
ENAME (AGE < 30 (EMP))
ENAME (PNAME=‘CAD/CAM” (PROJ) PNO (WORKS ENOEMP))

6. Tuple Relational Calculus
A formula F is Composed of
Atoms
Boolean operators ¬
Existential Qualifier 
Universal Qualifier 
Formation rules:
Each Atom is a Formula
If F and G are Formulae, so are FG, FG, ¬F, and ¬G
If F is a Formula, so is (F)
If F is a Formula and t is a Free variable in F, then  t(F) and t(F) are also Formulae
Nothing else is a Formula

7. Tuple Relational Calculus
The Atoms are the Following :
Tuple variables R.t or R(t)
Conditions
s[A] t
where s and t are Tuple Variables and A and B are Components of s and t, Respectively, and
<><=>=
specifies that Component A of s stands in relation to component B of t (e.g., s[SALARY] > t[SALARY])
s[A] c
where s, A and  are as Defined above and c is a Constant e.g., s[NAME] = 'Smith'.

8. Example
Find the names of Employees who have Worked for a Project for more than Two Years
{ t[ENAME] | tEMP u(u WORKS t[ENO]u
u[DUR]=‘24’))
Find all Managers who are less than 40 years old?
{ t[MGR] | tPROG u(u WORKS t[PNO]uPN
v(vEMPu[ENO]=v[ENO] v[AGE]<40)) 
ENAME (DUR=24 (WORKS) ENO EMP)
MGR (AGE<40 EMP ENO (WORKS PNOPROJ))

9. SQL: Tuple Relational Calculus-Based
SQL is a Partial Example of a Tuple Relational Language
Simple Queries are all Declarative
More Complex Queries are both Declarative and Procedural (e.g., joins, nested queries)
Find the names of employees working on the CAD/CAM project
SELECT EMP.ENAME
FROM EMP, WORKS, PROJ
WHERE (EMP.ENO= WORKS.ENO)
AND (WORKS.PNO = PROJ.PNO)
AND (PROJ.PNAME = “CAD/CAM”)
Tuple Variables are Implicit

10. Explicit Tuple Variables
Find the Pairs of all Project Names for those Projects that are Located at the same Place
SELECT (P1.PNAME, P2.PNAME)
FROM PROJ P1, PROJ P2
WHERE P1.LOC = P2.LOC
PNAME, PNAME1 (PROJ LOC = LOC1 PROJ1)
Let Proj1(PNAME1, LOC1) = PNAME, LOC (PROJ)

11. SQL Components Data Definition Language (DDL)
For External and Conceptual Schemas
Views - DDL for External Schemas
Data Manipulation Language (DML)
Interactive DML Against External and Conceptual Schemas
Embedded DML in Host PLs (EQL, JDBC, etc.)
Others
Integrity (Allowable Values/Referential)
Catalog and Dictionary Facilities
Transaction Control (Long-Duration and Batch)
Authorization (Who can Do What When)

12. SQL DDL and DML Data Definition Language (DDL)
Defining the Relational Schema - Relations, Attributes, Domains - The Meta-Data
CREATE TABLE Student:
Name(CHAR(30)), SSN(CHAR(9)), GPA(FLOAT(2))
CREATE TABLE Courses:
Course#(CHAR(6)), Title(CHAR(20)), Descrip(CHAR(100)), PCourse#(CHAR(6))
Data Manipulation Language (DML)
Defining the Queries Against the Schema
SELECT Name, SSN
From Student
Where GPA > 3.00

13. History of SQL SQL is based on the Relational Tuple Calculus
Evolved from SEQUEL: Structured English QUEry Language - part of IBM’s SYSTEM R, 1974
SQL2 Supported by
ORACLE, SYBASE, INFORMIX,
IBM DB2, SQL SERVER, …
MS Access, MySQL, …
SQL2 also called SQL/92 is evolved from SQL/86, SQL/89, all were ANSI & ISO standard
Ongoing work on SQL3 with OO Extensions

14. Data Definition Language - DDL
A Pre-Defined set of Primitive Types
Numeric
Character-string
Bit-string
Additional Types
Defining Domains
Defining Schema
Defining Tables
Defining Views
Note: Each DBMS May have their Own DBMS Specific Data Types - Is this Good or Bad?
primitive types
numeric (integers, floating-point real number REAL, DOUBLE PRECISION, FLOAT(N) DECIMAL(P,D), with P digits of which D are to the right of the decimal point
character-string
CHAR(N) (or CHARACTER(N)) is a fixed-length character string
VARCHAR(N) (or CHAR VARYING(N), or CHARACTER VARYING(N)) is a variable-length character string with at most N characters
bit-strings
BIT(N) is a fixed-length bit string
VARBIT(N) (or BIT VARYING(N)) is a bit string with at most N bits

15. DDL - Primitive Types Numeric INTEGER (or INT), SMALLINT
REAL, DOUBLE PRECISION
FLOAT(N) Floating Point with at Least N Digits
DECIMAL(P,D) (DEC(P,D) or NUMERIC(P,D)) have P Total Digits with D to Right of Decimal
Note that INTs and REALs are Machine Dependent (Based on Hardware/OS Platform)
primitive types
numeric (integers, floating-point real number REAL, DOUBLE PRECISION, FLOAT(N) DECIMAL(P,D), with P digits of which D are to the right of the decimal point
character-string
CHAR(N) (or CHARACTER(N)) is a fixed-length character string
VARCHAR(N) (or CHAR VARYING(N), or CHARACTER VARYING(N)) is a variable-length character string with at most N characters
bit-strings
BIT(N) is a fixed-length bit string
VARBIT(N) (or BIT VARYING(N)) is a bit string with at most N bits

16. DDL - Primitive Types Character-String CHAR(N) or CHARACTER(N) - Fixed
VARCHAR(N), CHAR VARYING(N), or CHARACTER VARYING(N) Variable with at Most N Characters
Bit-Strings
BIT(N) Fixed
VARBIT(N) or BIT VARYING(N) Variable with at Most N Bits
primitive types
numeric (integers, floating-point real number REAL, DOUBLE PRECISION, FLOAT(N) DECIMAL(P,D), with P digits of which D are to the right of the decimal point
character-string
CHAR(N) (or CHARACTER(N)) is a fixed-length character string
VARCHAR(N) (or CHAR VARYING(N), or CHARACTER VARYING(N)) is a variable-length character string with at most N characters
bit-strings
BIT(N) is a fixed-length bit string
VARBIT(N) (or BIT VARYING(N)) is a bit string with at most N bits

17. DDL - Primitive Types These Specialized Primitive Types are Used to:
Simplify Modeling Process
Include “Popular” Types
Reduce Composite Attributes/Programming
DATE : YYYY-MM-DD
TIME: HH-MM-SS
TIME(I): HH-MM-SS-F....F - I Fraction Seconds
TIME WITH TIME ZONE: HH-MM-SS-HH-MM
TIME-STAMP: YYYY-MM-DD-HH-MM-SS-F...F{-HH-MM}
NOTE: Different DBMS have Different Date/Time
primitive types
numeric (integers, floating-point real number REAL, DOUBLE PRECISION, FLOAT(N) DECIMAL(P,D), with P digits of which D are to the right of the decimal point
character-string
CHAR(N) (or CHARACTER(N)) is a fixed-length character string
VARCHAR(N) (or CHAR VARYING(N), or CHARACTER VARYING(N)) is a variable-length character string with at most N characters
bit-strings
BIT(N) is a fixed-length bit string
VARBIT(N) (or BIT VARYING(N)) is a bit string with at most N bits

18. DDL - What are Domains?
Domains are Similar in Concepts to Programming Language Type Definitions
A Domain can be Defined as Follows:
CREATE DOMAIN CITY CHAR(15) DEFAULT ‘<Storrs>’;
CREATE DOMAIN SSNFORMAT CHAR(9);
Advantage of Using Domains
Changing a Domain Definition in One Place Changes it Consistently Everywhere it is Used
Default Values Can Be Defined for Domains
Constraints Can Be Defined for Domains

19. DDL - Dropping a Domain A Domain is Dropped As Follows:
DROP DOMAIN CITY RESTRICT;
DROP DOMAIN SSNFORMAT CASCADE;
Restrict:
Drop Operation Fails If the Domain is Used in Column Definitions
Cascade:
Drop Operation Causes Columns to be Defined Directly on the Underlying Data Type

20. What is a SQL Schema? A Schema in SQL is the Major Meta-Data Construct
Create a DB to Contain Multiple Tables
Supports the Definition of:
Relation - Table with Name
Attributes - Columns and their Types
Identification - Primary Key
Constraints - Referential Integrity (FK)
Two Part Definition
CREATE Schema - Named Database or Conceptually Related Tables
CREATE Table - Individual Tables of the Schema

21. DDL-Create/Drop a Schema
Creating a Schema: CREATE SCHEMA MY_COMPANY AUTHORIZATION Demurjian;
Schema MY_COMPANY bas Been Created and is Owner by the User “Demurjian”
Tables can now be Created and Added to Schema
Dropping a Schema: DROP SCHEMA MY_COMPANY RESTRICT; DROP SCHEMA MY_COMPANY CASCADE;
Restrict:
Drop Operation Fails If Schema is Not Empty
Cascade:
Drop Operation Removes Everything in the Schema

22. DDL - Create Tables CREATE TABLE EMPLOYEE
( FNAME VARCHAR(15) NOT NULL ,
MINIT CHAR ,
LNAME VARCHAR(15) NOT NULL ,
SSN CHAR(9) NOT NULL ,
BDATE DATE
ADDRESS VARCHAR(30) ,
SEX CHAR ,
SALARY DECIMAL(10,2) ,
SUPERSSN CHAR(9) ,
DNO INT NOT NULL ,
PRIMARY KEY (SSN) ,
FOREIGN KEY (SUPERSSN) REFERENCES EMPLOYEE(SSN) ,
FOREIGN KEY (DNO)
REFERENCES DEPARTMENT(DNUMBER) ) ;

23. DDL - Create Tables (continued)
CREATE TABLE DEPARTMENT
( DNAME VARCHAR(15) NOT NULL , DNUMBER INT NOT NULL , MGRSSN CHAR(9) NOT NULL ,
MGRSTARTDATE DATE ,
PRIMARY KEY (DNUMBER) ,
UNIQUE (DNAME) ,
FOREIGN KEY (MGRSSN)
REFERENCES EMPLOYEE(SSN) ) ;
CREATE TABLE DEPT_LOCATIONS
(DNUMBER INT NOT NULL ,
DLOCATION VARCHAR(15) NOT NULL , PRIMARY KEY (DNUMBER, DLOCATION) ,
FOREIGN KEY (DNUMBER)
REFERENCES DEPARTMENT(DNUMBER) ) ;

24. DDL - Create Tables (continued)
CREATE TABLE PROJECT
(PNAME VARCHAR(15) NOT NULL , PNUMBER INT NOT NULL , PLOCATION VARCHAR(15) , DNUM INT NOT NULL , PRIMARY KEY (PNUMBER) , UNIQUE (PNAME) ,
FOREIGN KEY (DNUM) REFERENCES DEPARTMENT(DNUMBER) ) ;
CREATE TABLE WORKS_ON
(ESSN CHAR(9) NOT NULL , PNO INT NOT NULL ,
HOURS DECIMAL(3,1) NOT NULL , PRIMARY KEY (ESSN, PNO) , FOREIGN KEY (ESSN) REFERENCES EMPLOYEE(SSN) , FOREIGN KEY (PNO) REFERENCES PROJECT(PNUMBER) ) ;

25. DDL - Create Tables with Constraints
CREATE TABLE EMPLOYEE
( ,
DNO INT NOT NULL DEFAULT 1,
CONSTRAINT EMPPK
PRIMARY KEY (SSN) ,
CONSTRAINT EMPSUPERFK
FOREIGN KEY (SUPERSSN)
REFERENCES EMPLOYEE(SSN)
ON DELETE SET NULL
ON UPDATE CASCADE ,
CONSTRAINT EMPDEPTFK
FOREIGN KEY (DNO)
REFERENCES DEPARTMENT(DNUMBER)
ON DELETE SET DEFAULT
ON UPDATE CASCADE );

26. DDL - Create Tables with Constraints
CREATE TABLE DEPARTMENT
( ,
MGRSSN CHAR(9) NOT NULL
DEFAULT ' ' ,
. . . ,
CONSTRAINT DEPTPK
PRIMARY KEY (DNUMBER) ,
CONSTRAINT DEPTSK
UNIQUE (DNAME),
CONSTRAINT DEPTMGRFK
FOREIGN KEY (MGRSSN)
REFERENCES EMPLOYEE(SSN)
ON DELETE SET DEFAULT ON UPDATE CASCADE );

27. Create and Drop: Summary
Defines Types and Order of Attributes in a Relation
May Specify Which Attribute Are Keys and Which Cannot Be Null
Create a New Empty Table
May Define DELETION Effect by Cascade/Restricted
CREATE TABLE Supplier_Parts
( S# CHAR(5) NOT NULL,
P# CHAR(6) NOT NULL,
QTY INTEGER,
PRIMARY KEY (S# P#)
FOREIGN KEY S#
REFERENCE SUPPLIER
ON DELETE CASCADE,
REFERENCE PART
ON DELETE RESTRICT);

28. SQL Data Definition Drop Table A Relation Can Be Dropped at Any Time
Drop Will Delete Both Definition and Data
All Views, Indexes, and FKs are Dropped DROP TABLE SUPPLIER;
Alter Table
Add New Attributes or PK and FK to the Table
All Existing Records are Expanded With Nulls, but Not Physically Changed. ALTER TABLE SUPPLIER ADD DISCOUNT SMALLINT;

29. DDL - Drop Tables Command: DROP TABLE EMPLOYEE RESTRICT;
DROP TABLE DEPARTMENT CASCADE;
Restrict:
Drop Operation fails if the Table is Referenced by View and/or Constraint Definitions
Cascade:
Drop Operation Removes Referencing View and Constraint Definitions

30. DDL - Change Table Structure
Add a Column to a Table:
ALTER TABLE EMPLOYEE
ADD JOB VARCHAR(12);
No DEFAULT Implies NULL Values for all Tuples
Drop a Column from a table ALTER TABLE EMPLOYEE DROP JOB RESTRICT (or CASCADE);
Restrict: Drop Operation Fails if Column is Referenced
Cascade: Drop Operation Removes Referencing View and Constraint Definitions

31. Chinook sql file

32. Chinook sql file

33. Chinook sql file

34. Chinook sql file

35. Chinook sql file

36. Data Manipulation Language - DML
SQL has the SELECT Statement for Retrieving Info. from a Database (Not Relational Algebra Select)
SQL vs. Formal Relational Model
SQL Allows a Table (Relation) to have Two or More Identical Tuples in All Their Attribute Values
Hence, an SQL Table is a Multi-set (Sometimes Called a Bag) of Tuples; it is Not a Set of Tuples
SQL Relations Can Be Constrained to Sets by
PRIMARY KEY or UNIQUE Attributes
Using the DISTINCT Option in a Query
primitive types
numeric (integers, floating-point real number REAL, DOUBLE PRECISION, FLOAT(N) DECIMAL(P,D), with P digits of which D are to the right of the decimal point
character-string
CHAR(N) (or CHARACTER(N)) is a fixed-length character string
VARCHAR(N) (or CHAR VARYING(N), or CHARACTER VARYING(N)) is a variable-length character string with at most N characters
bit-strings
BIT(N) is a fixed-length bit string
VARBIT(N) (or BIT VARYING(N)) is a bit string with at most N bits

37. Interactive DML - Main Components
Select-from-where Statement Contains:
Select Clause - Chosen Attributes/Columns
From Clause - Involved Tables
Where Clause - Constrain Tuple Values
Tuple Variables - Distinguish Among Same Names in Different Tables
String Matching - Detailed Matching Including
Exact
Starts With
Near
Ordering of Rows - Sorting Tuple Results

38. Interactive DML - Main Components
Select-from-where Statement Contains:
Set Operations - Search to See if a Value is in Set
Built-in Functions - Count, Mix, Max, Sum, Avg
Nested Subqueries - Queries within Queries
Joins - As Discussed for Relational Algebra
Recursive Queries (Defer - Part of SQL3)
Modification-Based Selects for
Insert - Create a New Tuple
Delete - Remove Existing Tuple(s)
Update - Change Existing Tuple(s)

39. SQL Data Manipulation target-listconditionrelation-list
Skeleton Query:
SELECT target-list
FROM relation-list
WHERE condition or subquery
GROUP BY attribute-list
HAVING condition
ORDER BY attribute-list
SELECT - relational “project”
WHERE - relational “select” and/or “join”
In principle, a SQL query equals to an algebra expression
target-listconditionrelation-list

40. Simple Select-From-Where
Format:
Equivalent Algebra Statement:
SELECT Specifies the Columns of the Query Result
FROM Specifies the Tables to Be Used in the Query
WHERE Specifies the Query Condition
Restriction: Must Refer to Columns of the Tables in the FROM Clause
SELECT A1, A2, ... An
FROM R1 , R2 , ... Rm
WHERE Predicate (Boolean/Set Expression) p A 1 , 2
, ... n ( s P R
 R m ))
 ... 

41. Recall Prior Schema

42. …and Corresponding DB Tables
Which Represent Tuples/Instances of Each Relation A S C
null W B 1 4 5

43. …and Corresponding DB Tables

44. Simple SQL Queries
Query 0: Retrieve the Birthdate and Address of the Employee whose Name is 'John B. Smith'. SELECT BDATE, ADDRESS FROM EMPLOYEE WHERE FNAME='John' AND MINIT='B’ AND LNAME='Smith’
Which Row(s) are Selected?
Note: While All of these Next Queries are from Chapter 4, Some are From “Earlier” Edition B S C
null W

45. Simple SQL Queries
Query 1: Retrieve Name and Address of all Employees who work for the 'Research' Department SELECT FNAME, MINIT, LNAME, ADDRESS, DNAME FROM EMPLOYEE, DEPARTMENT WHERE DNAME='Research' AND DNUMBER=DNO
What Action is Being Performed?

46. Simple SQL Queries - Result
Theta Join on DNO=DNUMBER

47. Simple SQL Queries – Fully Qualified
The Full Table Name with “.” Notation Differentiates Among the Attributes
Query 1: Retrieve Name and Address of all Employees who work for the 'Research' Department SELECT EMPLOYEE.FNAME, EMPLOYEE.MINIT, EMPLOYEE. LNAME,EMPLOYEE.ADDRESS, DEPARTMENT.DNAME FROM EMPLOYEE, DEPARTMENT WHERE DEPARTMENT.DNAME='Research' AND DEPARTMENT.DNUMBER= EMPLOYEE.DNO

48. Simple SQL Queries
Query 2: For Every Project in 'Stafford', list the Project Number, the Controlling Dept. Number, and the Dept. Manager's Last Name, Address, and Birthdate SELECT PNUMBER, DNUM, LNAME, BDATE,ADDRESS FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE DNUM=DNUMBER AND MGRSSN=SSN AND PLOCATION='Stafford'
In Q2, there are Two Join Conditions:
The Join Condition DNUM=DNUMBER Relates a Project to its Controlling Department
The Join Condition MGRSSN=SSN Relates the Controlling Department to the Employee who Manages that Department

49. Query Results
SELECT PNUMBER, DNUM, LNAME, BDATE,ADDRESS FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE DNUM=DNUMBER AND MGRSSN=SSN AND PLOCATION='Stafford' A S C
null W B

50. Qualification of Attributes
In SQL, the Same Name for Two (or More) Attributes is Allowed if Attributes are in Different Relations
In Those Cases, Query Must Qualify by Prefixing the Relation Name to the Attribute Name
EMPLOYEE.LNAME, DEPARTMENT.DNAME
Aliases: When Queries Must Refer to the Same Relation Twice
Alias is Akin to a Variable in a PL - Reference
In These Situations, it is Considered that there are Two Different Copies of the Same Relation
Let’s See Examples of Both Concepts

51. Attribute Qualification
Query 8: For Each Employee, Retrieve the Employee's Name, and Name of his or her Immediate Supervisor SELECT E.FNAME, E.LNAME, S.FNAME, S.LNAME FROM EMPLOYEE E S WHERE E.SUPERSSN=S.SSN
E and S are aliases for the EMPLOYEE relation
E Represents Employees in the Role of Supervisees
S Represents Employees in the Role of Supervisor
Another Form of Query 8 is: SELECT E.FNAME, E.LNAME, S.FNAME, S.LNAME FROM EMPLOYEE AS E, EMPLOYEE AS S WHERE E.SUPERSSN=S.SSN

52. Query Results – Refer to Same Table Twice
SELECT E.FNAME, E.LNAME, S.FNAME, S.LNAME FROM EMPLOYEE AS E, EMPLOYEE AS S WHERE E.SUPERSSN=S.SSN A S C
null W B

53. Conceptually There are two Separate Tables
System Goes Through Every Row of Top Against Every Row of Bottom
This is Conceptual
In Reality – Only 1 Table Exists
EMPLOYEE AS E A S C
null W B
EMPLOYEE AS S A S C
null W B

54. Unspecified WHERE Clause
A Missing Where-clause Indicates No Condition; All Tuples of Relations in From-clause Are Selected
Query 9: Retrieve the SSN Values for All Employees SELECT SSN FROM EMPLOYEE

55. Unspecified WHERE Clause
More Than One Relation and No Join Condition Results in the CARTESIAN PRODUCT of Tuples
Query 10: SELECT SSN, DNAME FROM EMPLOYEE, DEPARTMENT
Overlooking Selection and Join Conditions in the Where-Clause Likely Yields Incorrect and Very Large Relations May Result – What Happens with these?

56. How Many Tuples are Generated?
Every Row of Employee table is matched with Every Row of the Department table
8 times 3 – means 24 Rows
Most are useless….

57. Use of * and Distinct
When a * is Used, All of the Attributes are Chosen Q1C: SELECT * FROM EMPLOYEE WHERE DNO=5

58. Use of * and Distinct
When a * is Used, All of the Attributes are Chosen Q1D: SELECT * FROM EMPLOYEE, DEPARTMENT WHERE DNAME='Research' AND DNO=DNUMBER

59. Use of * and Distinct
SQL Does Not Support Sets so Duplicates are Retrieved Q11: SELECT SALARY FROM EMPLOYEE
Q11A: SELECT DISTINCT SALARY FROM EMPLOYEE

60. SELECT * in MySQL WorkBench

61. SELECT * in MySQL WorkBench

62. Set Operations - Union/Intersection/Minus
Not all DBMS Support Intersection/Minus
Union: The two Relations must have Same Attributes and the Attributes must Appear in the Same Order
Query 4: All Project Numbers for Projects with Employee 'Smith' as a Worker or as a Manager (SELECT PNAME FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE DNUM=DNUMBER AND MGRSSN=SSN AND LNAME='Smith') UNION (SELECT PNAME FROM PROJECT, WORKS_ON, EMPLOYEE WHERE PNUMBER=PNO AND ESSN=SSN AND LNAME='Smith')

63. Set Operations - Union/Intersection/Minus
(SELECT PNAME FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE DNUM=DNUMBER AND MGRSSN=SSN AND LNAME='Smith')
UNION
(SELECT PNAME FROM PROJECT, WORKS_ON, EMPLOYEE WHERE PNUMBER=PNO AND ESSN=SSN AND LNAME='Smith')

64. Set Operations - Union/Intersection/Minus
Utilizing the DISTINCT KEYWORD
Query 4: Make a list of all project numbers for projects that involve an employee whose last name is ‘Smith’, either as a worker or as a manager of the department that controls the project. (SELECT DISTINCT PNAME FROM PROJECT, DEPARTMENT, EMPLOYEE WHERE DNUM=DNUMBER AND MGRSSN=SSN AND LNAME='Smith') UNION (SELECT DISTINCT PNAME FROM PROJECT, WORKS_ON, EMPLOYEE WHERE PNUMBER=PNO AND ESSN=SSN AND LNAME='Smith')

65. Substring Comparison in SQL Queries
In Regard to Strings, Most DBMSs Support SQL Queries for Exact, Near, and Starts with Matching
LIKE is Used to Compare Partial Strings
'%' (or '*') Replaces an Arbitrary # of characters '_' replaces a single arbitrary character
Query 12: Retrieve all Employees whose Address is in Houston, Texas. SELECT FNAME, LNAME FROM EMPLOYEE WHERE ADDRESS LIKE '%Houston,TX% '
Houston, TX can be anywhere within the ADDRESS VAR CHAR String

66. Substring Comparison in SQL Queries
The LIKE Operator Allows us to get Around the Fact that each Value is Considered Atomic and Indivisible
SQL: Character String Attribute values are not Atomic
Query 12A: Retrieve all employees who were born during the 1950s. SELECT FNAME, LNAME FROM EMPLOYEE WHERE BDATE LIKE ' __5_______'
There are two “_” before 5 and seven “_” after 5
Underscores are “blanks”

67. Arithmetic Operations in SQL Queries
Standard Arithmetic Operators '+', '-'. '*', and '/' can be Applied to Numeric Values in an SQL Query Result
Query 13: Show the Effect of Giving all Employees who work on the 'ProductX' project a 10% raise. SELECT FNAME, LNAME, 1.1*SALARY FROM EMPLOYEE, WORKS_ON, PROJECT WHERE SSN=ESSN AND PNO=PNUMBER AND PNAME='ProductX'
This Doesn’t Change the Table – just Output!

68. ORDER BY Clause in SQL Queries
ORDER BY used to Sort the Tuples in a Query Result based on the Values of one or More Attribute(s)
Query 15: Retrieve a list of Employees and the Projects each works in, ordered by Dept., and within each Dept., alphabetically by Employee last name SELECT DNAME, LNAME, FNAME, PNAME FROM DEPARTMENT, EMPLOYEE, WORKS_ON, PROJECT WHERE DNUMBER=DNO AND SSN=ESSN AND PNO=PNUMBER ORDER BY DNAME, LNAME
Default is Ascending - Can be ASC/DESC as we’ll see in a Later Example in Chapter 5

69. Natural Join Queries
Specially Tells SQL that a Natural Join is Defined Between Tables
SELECT * FROM COUNTRIES NATURAL JOIN CITIES
SELECT * FROM COUNTRIES JOIN CITIES USING (COUNTRY, COUNTRY_ISO_CODE)
Note that * Expands the JOIN in 1st Query to:
All the common columns
Every column in the first (left) table that is not a common column
Every column in the second (right) table that is not a common column
Natural Join in the FROM LIST

70. Homework 3 from Spr 2015
Problem 6.18 from the 6th edition done in SQL and NOT relational expressions

71. Problem 6.18 in 6th edition
How many copies of the book titled The Lost Tribe are owned by the
library branch whose name is ‘Sharpstown’?
SELECT NoOfCopies
FROM ( (BOOK NATURAL JOIN BOOK_COPIES )
NATURAL JOIN LIBRARY_BRANCH )
WHERE Title='The Lost Tribe' AND BranchName='Sharpstown’
BaB= (BOOKCOPIES *(Title=‘The Lost Tribe’ (BOOK))) )
BookId
Ans = No_Of_Copies( (BranchName=‘Sharpstown’ (LIBRARY-BRANCH)) * BaB)
BranchID

72. Problem 6.18 in 6th edition BranchId
b. How many copies of the book titled The Lost Tribe are owned by each
library branch?
SELECT BranchName, NoOfCopies
FROM ( (BOOK NATURAL JOIN BOOK_COPIES )
NATURAL JOIN LIBRARY_BRANCH )
WHERE Title='The Lost Tribe'
CaB = BOOKCOPIES * LIBRARY_BRANCH)
BranchId
Ans = BranchName, No_Of_Copies( (Title=‘The Lost Tribe’ (BOOK)) * CaB)
BookId

73. Homework 3 from Spr 2015
Problem 4.10 in 6th edition

74. Problem 4.10 in 6th edition

75. Problem 4.10 in 6th edition
(a) Retrieve the names of employees in department 5 who
work more than 10 hours per week on the 'ProductX' project.
SELECT LNAME, FNAME
FROM EMPLOYEE, WORKS_ON, PROJECT
WHERE DNO=5 AND SSN=ESSN AND
PNO=PNUMBER AND PNAME='ProductX' AND HOURS>10
Result:
LNAME FNAME
Smith John
English Joyce

76. Problem 4.10 in 6th edition Result (empty):
(b) List the names of employees who have a dependent
with the same first name as themselves.
SELECT LNAME, FNAME
FROM EMPLOYEE, DEPENDENT
WHERE SSN=ESSN AND FNAME=DEPENDENT_NAME
Result
(empty):

77. Problem 4.10 in 6th edition (c) Find the names of employees that are
directly supervised by 'Franklin Wong'.
SELECT E.LNAME, E.FNAME
FROM EMPLOYEE E, EMPLOYEE S
WHERE S.FNAME='Franklin' AND
S.LNAME='Wong' AND E.SUPERSSN=S.SSN
Result:
LNAME FNAME
Smith John
Narayan Ramesh
English Joyce

78. Problem 4.10 in 6th edition Result: AVG(SALARY) 31000
(h) Retrieve the average salary of all female employees.
SELECT AVG (SALARY)
FROM EMPLOYEE
WHERE SEX='F’
Result:
AVG(SALARY)
31000

79. Other SQL Queries Hmwk 4 Spring 2015
Problem 3.4 for the Northwind Database Schema
Find and print the company names and company addresses of all Suppliers that supply the category name Seafood.
Count and print the number of suppliers for each of the eight different categories of food which by name are: Beverages, Condiments, Confections, Dairy Products, Grains/Cereals, Meat/Poultry, Produce, Seafood.
For each country (ShipCountry in Orders), total the Freight charges. The countries are: France, Germany, Brazil, Belgium, Switzerland, Venezuela, Austria, Mexico, USA, Sweden, Finland, Italy, Spain, UK, Ireland, Portugal, Canada, Denmark, Poland, Norway, Argentina

80. Explaining Northwind Schema
Suppliers: A Suppliers Contact Info and web link.
Products: Names, suppliers, and Prices
Categories: Categories of Northwind products such as Beverages, Condiments, Confections, Dairy Products, Grains/Cereals, Meat/Poultry, Produce, Seafood
Orders: For each Customer with dates &Shipping
Order Details: Products, quantities, and price.
Employees: Typical Info.
Customers: Typical Info.
Shippers: Typical Info.

81. Northwind Schema

82. Northwind Schema – Key Types

83. Find and print the company names and company addresses of all Suppliers that supply the category name Seafood.
SELECT DISTINCT suppliers.CompanyName, suppliers.Address
FROM northwind.suppliers, northwind.categories, northwind.products
WHERE suppliers.SupplierID = products.SupplierID
AND categories.CategoryID = products.CategoryID
AND categories.CategoryName = 'Seafood';

84. Count/the number of suppliers for each of the eight different categories of food which by name are: Beverages, Condiments, Confections, Dairy Products, Grains/Cereals, Meat/Poultry, Produce, Seafood.
SELECT categories.CategoryName, COUNT(suppliers.SupplierID)
FROM northwind.categories, northwind.products, northwind.suppliers
WHERE suppliers.SupplierID = products.SupplierID
AND products.categoryID = categories.CategoryID
GROUP BY categories.CategoryName;

85. For each country (ShipCountry in Orders), total the Freight charges.
SELECT orders.ShipCountry, SUM(orders.Freight)
FROM northwind.orders
GROUP BY orders.ShipCountry;

86. Other SQL Queries Hmwk 2 Fall 2015
Problem 3.4 for the Northwind Database Schema
Find the list of all customers from United Kingdom sorted by Company Name in ascending order and return the company Name and Country.
Find the number of customers that are located in each country.
Find the Product Name, UnitPrice, and UnitsInStock and Sorted by ProductName for all products where the product name starts with “Ch”.

87. Find list of all customers from United Kingdom
SELECT northwind.suppliers.CompanyName, northwind.suppliers.country
FROM northwind.suppliers
WHERE northwind.suppliers.Country="UK"
ORDER BY northwind.suppliers.CompanyName ASC
Exotic Liquids UK
Specialty Biscuits, Ltd.

88. Find number of customers in each country.
Argentina 3
Austria 2
Belgium
Brazil 9
Canada
Denmark
Finland
France 11
Germany
Ireland 1
Italy
Mexico 5
Norway
Poland
Portugal
Spain
Sweden
Switzerland UK 7
USA 13
Venezuela 4
SELECT northwind.customers.country, COUNT(*)
FROM northwind.customers
WHERE northwind.customers.country IS NOT NULL
GROUP BY northwind.customers.country

89. Find the Product Name …starts with “Ch”.
SELECT northwind.products.productid, northwind.products.productname,
northwind.products.UnitsinStock
FROM northwind.products
WHERE northwind.products.productname LIKE 'CH%'; 1
Chai 39 2
Chang 17
Chartreuse verte 69 4
Chef Anton's Cajun Seasoning 53 5
Chef Anton's Gumbo Mix 48
Chocolade 15

90. INSERT SQL Queries
Add one or more Tuples to a Relation, with Attribute values Listed in the order specified in the CREATE
Update 1: INSERT INTO EMPLOYEE VALUES ('Richard','K','Marini', ' ', '30-DEC-52', '98 Oak Forest,Katy,TX', 'M', ,' ', 4 )
Another Form of Update 1: INSERT INTO EMPLOYEE (FNAME, LNAME, SSN) VALUES ('Richard','K','Marini')
All PK and FK Values must be Provided
Nulls are Allowed
DDL Constraints are Enforced

91. INSERT SQL Queries More Sophisticated Insert can Involve Query
Update 3A: CREATE TABLE DEPTS_INFO (DEPT_NAME VARCHAR(10), NO_OF_EMPS INTEGER, TOTAL_SAL INTEGER);
Update 3B: INSERT INTO DEPTS_INFO (DEPT_NAME, NO_OF_EMPS, TOTAL_SAL) SELECT DNAME, COUNT (*), SUM (SALARY) FROM DEPARTMENT, EMPLOYEE WHERE DNUMBER=DNO GROUP BY DNAME ;

92. Program Level INSERTS
Mass Import into DB Consider Chinook_MySql.sql

93. Program Level INSERTS Importing Excel Directly into MySQL
Many Available Tools
Importing an XML File directly into MySQL
LOAD XML LOCAL INFILE '/pathtofile/file.xml' INTO TABLE my_tablename SET ID=NULL;
Tools such as:
Likewise – Ability to EXPORT as well
SQL Data Export and Import Wizard
For MySQL See:

94. DELETE SQL Queries Sample Deletes Include
DELETE FROM EMPLOYEE WHERE LNAME='Brown'
DELETE FROM EMPLOYEE WHERE SSN=' ’
DELETE FROM EMPLOYEE WHERE DNO IN (SELECT DNUMBER FROM DEPARTMENT WHERE DNAME='Research')
DELETE FROM EMPLOYEE
No. of Tuples Deleted Dependent on WHERE Clause
Referential Integrity is Enforced During DELETE

95. UPDATE SQL Queries
Used to Modify Attribute Values of One or More Selected Tuples
A Where-clause Selects the Tuples to Be Modified
An Additional Set-Clause Specifies the Attributes to Be Modified and Their New Values
Each Command Modifies Tuples in the Same Relation
Referential Integrity Must Be Enforced UPDATE PROJECT SET PLOCATION = 'Bellaire', DNUM = 5 WHERE PNUMBER=10

96. UPDATE SQL Queries
Give all Employees in the 'Research' Dept. a 10% raise UPDATE EMPLOYEE SET SALARY = SALARY *1.1 WHERE DNO IN (SELECT DNUMBER FROM DEPARTMENT WHERE DNAME='Research')
Modified SALARY Value Depends on the Original SALARY Value in each Tuple
SALARY = SALARY *1.1 - Use PL Interpretation

97. Concluding Remarks What have we Seen in Chapter 4?
Complete Data Definition in SQL
Creating Schema
Creating/Dropping Tables
FKs and PKs
Basic Data Manipulation in SQL
Different Selects
Aggregate Functions
Insert, Update, and Delete
Strongly Encouraged to Engage in Practice with your DBMS of Choice for your Project

98. Jump to Homework 2 in cse4701ann.pptx