DataBase DML - SQL. This content about SQL

 Writing basic SQL statements
Writing basic SQL statements
 Restricting and Sorting Data
Restricting and Sorting Data
 Single
Single-
-Row Functions
Row Functions
 Multiple
Multiple-
-Row Functions
Row Functions (Group functions)
(Group functions)
 Manipulating Data
Manipulating Data (DML)
(DML)
(Insert, Update and Delete)
(Insert, Update and Delete)
CH3 Part1
CH3 Part1

Writing Basic
Writing Basic
SQL Statements
SQL Statements

SQL Scripts
SQL Scripts
 Script: text file that contains a sequence of SQL
Script: text file that contains a sequence of SQL
commands
commands
 Usually have .sql extension
Usually have .sql extension
 To run from SQL*Plus:
To run from SQL*Plus:
 Start full file path
Start full file path
SQL> START path_to_script_file;
SQL> START path_to_script_file;
 @ full file path
@ full file path (
(SQL>
SQL> @
@ path_to_script_file;)
path_to_script_file;)
 Extension can be omitted if it is .sql
Extension can be omitted if it is .sql
 Path cannot contain any blank spaces
Path cannot contain any blank spaces

Objectives
Objectives
 After completing this lesson, you should be
After completing this lesson, you should be
able to do the following
able to do the following:
:
 List the capabilities of SQL SELECT
List the capabilities of SQL SELECT
statements
statements
 Execute a basic SELECT statement
Execute a basic SELECT statement
 Differentiate between SQL statements and
Differentiate between SQL statements and
SQL
SQL*
*Plus commands
Plus commands

Capabilities of SQL SELECT
Capabilities of SQL SELECT
Statements
Statements
Selection
Selection Projection
Projection
Table 1
Table 1 Table 2
Table 2
Table 1
Table 1 Table 1
Table 1
Join
Join

Basic SELECT Statement
Basic SELECT Statement
SELECT [DISTINCT] {*, column [alias],...}
FROM table;
 SELECT identifies
SELECT identifies what
what columns
columns.
.
 FROM identifies
FROM identifies which
which table
table.
.

Writing SQL Statements
Writing SQL Statements
 SQL statements are not case sensitive
SQL statements are not case sensitive.
.
 SQL statements can be on one or
SQL statements can be on one or
more lines
more lines.
.
 Keywords cannot be abbreviated or split
Keywords cannot be abbreviated or split
across lines
across lines.
.
 Clauses are usually placed on separate lines
Clauses are usually placed on separate lines.
.
 Tabs and indents are used to enhance
Tabs and indents are used to enhance
readability
readability.
.

Selecting All Columns
Selecting All Columns
DEPTNO DNAME LOC
--------- -------------- -------------
10 ACCOUNTING NEW YORK
20 RESEARCH DALLAS
30 SALES CHICAGO
40 OPERATIONS BOSTON
SQL> SELECT *
2 FROM dept;

Selecting Specific Columns
Selecting Specific Columns
DEPTNO LOC
--------- -------------
10 NEW YORK
20 DALLAS
30 CHICAGO
40 BOSTON
SQL> SELECT deptno, loc
2 FROM dept;

Column Heading Defaults
Column Heading Defaults
 Default justification
Default justification
 Left
Left:
: Date and character data
Date and character data
 Right
Right:
: Numeric data
Numeric data
 Default display
Default display:
: Uppercase
Uppercase

Arithmetic Expressions
Arithmetic Expressions
 Create expressions on NUMBER and DATE
Create expressions on NUMBER and DATE
data by using arithmetic operators
data by using arithmetic operators.
.
Operator
+
-
*
/
Description
Add
Subtract
Multiply
Divide

Using Arithmetic Operators
SQL> SELECT ename, sal, sal+300
2 FROM emp;
ENAME SAL SAL+300
---------- --------- ---------
KING 5000 5300
BLAKE 2850 3150
CLARK 2450 2750
JONES 2975 3275
MARTIN 1250 1550
ALLEN 1600 1900
...
14 rows selected.

Operator Precedence
Operator Precedence
 Multiplication and division take priority over
Multiplication and division take priority over
addition and subtraction
addition and subtraction.
.
 Operators of the same priority are evaluated
Operators of the same priority are evaluated
from left to right
from left to right.
.
 Parentheses are used to force prioritized
Parentheses are used to force prioritized
evaluation and to clarify statements
evaluation and to clarify statements.
.
*
* /
/ +
+ _
_

Operator Precedence
Operator Precedence
SQL> SELECT ename, sal, 12*sal+100
2 FROM emp;
ENAME SAL 12*SAL+100
---------- --------- ----------
KING 5000 60100
BLAKE 2850 34300
CLARK 2450 29500
JONES 2975 35800
MARTIN 1250 15100
ALLEN 1600 19300
...
14 rows selected.

Using Parentheses
Using Parentheses
SQL> SELECT ename, sal, 12*(sal+100)
2 FROM emp;
ENAME SAL 12*(SAL+100)
---------- --------- -----------
KING 5000 61200
BLAKE 2850 35400
CLARK 2450 30600
JONES 2975 36900
MARTIN 1250 16200
...
14 rows selected.

Defining a Null Value
Defining a Null Value
 A null is a value that is unavailable,
A null is a value that is unavailable,
unassigned, unknown, or inapplicable
unassigned, unknown, or inapplicable.
.
 A null is not the same as zero or a blank space
A null is not the same as zero or a blank space.
.
ENAME JOB SAL COMM
---------- --------- --------- ---------
KING PRESIDENT 5000
BLAKE MANAGER 2850
...
TURNER SALESMAN 1500 0
...
14 rows selected.
SQL> SELECT ename, job, sal, comm
2 FROM emp;

Null Values
Null Values
in Arithmetic Expressions
in Arithmetic Expressions
 Arithmetic expressions containing a null
Arithmetic expressions containing a null
value evaluate to null
value evaluate to null.
.
SQL> select ename, 12*sal+comm
2 from emp
3 WHERE ename='KING';
ENAME 12*SAL+COMM
---------- -----------
KING

Defining a Column Alias
Defining a Column Alias
 Renames a column heading
Renames a column heading
 Is useful with calculations
Is useful with calculations
 Immediately follows column name; optional
Immediately follows column name; optional
AS keyword between column name and alias
AS keyword between column name and alias
 Requires double quotation marks if it contains
Requires double quotation marks if it contains
spaces or special characters or is case sensitive
spaces or special characters or is case sensitive

Using Column Aliases
Using Column Aliases
SQL> SELECT ename AS name, sal salary
2 FROM emp;
NAME SALARY
------------- ---------
...
SQL> SELECT ename "Name",
2 sal*12 "Annual Salary"
3 FROM emp;
Name Annual Salary
------------- -------------
...

Concatenation Operator
Concatenation Operator
 Concatenates columns or character strings to
Concatenates columns or character strings to
other columns
other columns
 Is represented by two vertical bars
Is represented by two vertical bars (
(||
||)
)
 Creates a resultant column that is a character
Creates a resultant column that is a character
expression
expression

Using the Concatenation
Using the Concatenation
Operator
Operator
SQL> SELECT ename||job AS "Employees"
2 FROM emp;
Employees
-------------------
KINGPRESIDENT
BLAKEMANAGER
CLARKMANAGER
JONESMANAGER
MARTINSALESMAN
ALLENSALESMAN
...
14 rows selected.

Literal Character Strings
Literal Character Strings
 A literal is a character, a number, or a date
A literal is a character, a number, or a date
included in the SELECT list
included in the SELECT list.
.
 Date and character literal values must be
Date and character literal values must be
enclosed within single quotation marks
enclosed within single quotation marks.
.
 Each character string is output once for each
Each character string is output once for each
row returned
row returned.
.

Using Literal Character Strings
Using Literal Character Strings
Employee Details
-------------------------
KING is a PRESIDENT
BLAKE is a MANAGER
CLARK is a MANAGER
JONES is a MANAGER
MARTIN is a SALESMAN
...
14 rows selected.
SQL> SELECT ename ||' is a '||job
2 AS "Employee Details"
3 FROM emp;

Duplicate Rows
Duplicate Rows
 The default display of queries is all rows,
The default display of queries is all rows,
including duplicate rows
including duplicate rows.
.
SQL> SELECT deptno
2 FROM emp;
DEPTNO
---------
10
30
10
20
...
14 rows selected.

Eliminating Duplicate Rows
Eliminating Duplicate Rows
Eliminate duplicate rows by using the
Eliminate duplicate rows by using the
DISTINCT keyword in the SELECT clause
DISTINCT keyword in the SELECT clause.
.
SQL> SELECT DISTINCT deptno
2 FROM emp;
DEPTNO
---------
10
20
30

SQL and SQL
SQL and SQL*
*Plus Interaction
Plus Interaction
SQL
SQL*
*Plus
Plus
SQL Statements
SQL Statements
Buffer
Buffer
SQL Statements
SQL Statements
Server
Query Results
Query Results
SQL
SQL*
*Plus
Plus
Commands
Commands
Formatted Report
Formatted Report

SQL Statements Versus
SQL Statements Versus
SQL
SQL*
*Plus Commands
Plus Commands
SQL
SQL
statements
statements
SQL
SQL
• A language
A language
• ANSI standard
ANSI standard
• Keyword cannot be
Keyword cannot be
abbreviated
abbreviated
• Statements manipulate
Statements manipulate
data and table
data and table
definitions in the
definitions in the
database
database
SQL
SQL*
*Plus
Plus
• An environment
An environment
• Oracle proprietary
Oracle proprietary
• Keywords can be
Keywords can be
abbreviated
abbreviated
• Commands do not
Commands do not
allow manipulation of
allow manipulation of
values in the database
values in the database
SQL
SQL
buffer
buffer
SQL
SQL*
*Plus
Plus
commands
commands
SQL
SQL*
*Plus
Plus
buffer
buffer

 Log in to SQL
Log in to SQL*
*Plus
Plus.
.
 Describe the table structure
Describe the table structure.
.
 Edit your SQL statement
Edit your SQL statement.
.
 Execute SQL from SQL
Execute SQL from SQL*
*Plus
Plus.
.
 Save SQL statements to files and append SQL
Save SQL statements to files and append SQL
statements to files
statements to files.
.
 Execute saved files
Execute saved files.
.
 Load commands from file to buffer
Load commands from file to buffer
to edit
to edit.
.
Overview of SQL
Overview of SQL*
*Plus
Plus

Logging In to SQL
Logging In to SQL*
*Plus
Plus
 From Windows environment
From Windows environment:
:
 From command line
From command line:
:
sqlplus
sqlplus [
[username
username[/
[/password
password
[
[@
@database
database]]]
]]]

Displaying Table Structure
 Use the SQL
Use the SQL*
*Plus DESCRIBE command to
Plus DESCRIBE command to
display the structure of a table
display the structure of a table.
.
DESC[RIBE] tablename

SQL> DESCRIBE dept
Name Null? Type
----------------- -------- ------------
DEPTNO NOT NULL NUMBER(2)
DNAME VARCHAR2(14)
LOC VARCHAR2(13)

SQL
SQL*
*Plus Editing Commands
Plus Editing Commands
 A
A[
[PPEND
PPEND]
] text
text
 C
C[
[HANGE
HANGE] /
] / old
old /
/ new
new
 C
C[
[HANGE
HANGE] /
] / text
text /
/
 CL
CL[
[EAR
EAR]
] BUFF
BUFF[
[ER
ER]
]
 DEL
DEL
 DEL
DEL n
n
 DEL
DEL m n
m n

SQL
SQL*
*Plus Editing Commands
Plus Editing Commands
 I
I[
[NPUT
NPUT]
]
 I
I[
[NPUT
NPUT]
] text
text
 L
L[
[IST
IST]
]
 L
L[
[IST
IST]
] n
n
 L
L[
[IST
IST]
] m n
m n
 R
R[
[UN
UN]
]
 n
n
 n
n text
text
 0
0 text
text

SQL
SQL*
*Plus File Commands
Plus File Commands
 SAVE
SAVE filename
filename
 GET
GET filename
filename
 START
START filename
filename
 @
@ filename
filename
 EDIT
EDIT filename
filename
 SPOOL
SPOOL filename
filename
 EXIT
EXIT

Summary
Summary
 Use SQL
Use SQL*
*Plus as an environment to
Plus as an environment to:
:
 Execute SQL statements
Execute SQL statements
 Edit SQL statements
Edit SQL statements
SELECT [DISTINCT] {*,column [alias],...}
FROM table;

Objectives
Objectives
 After completing this lesson, you should be able
After completing this lesson, you should be able
to do the following
to do the following:
:
 Limit the rows retrieved by a query
Limit the rows retrieved by a query
 Sort the rows retrieved by a query
Sort the rows retrieved by a query

Limiting Rows Using a Selection
Limiting Rows Using a Selection
"
"…retrieve all
…retrieve all
employees
employees
in department 10
in department 10"
"
EMP
EMP
EMPNO ENAME JOB ... DEPTNO
7839 KING PRESIDENT 10
7698 BLAKE MANAGER 30
7782 CLARK MANAGER 10
7566 JONES MANAGER 20
...
EMP
EMP
7934 MILLER CLERK 10

Limiting Rows Selected
Limiting Rows Selected
 Restrict the rows returned by using the
Restrict the rows returned by using the
WHERE clause
WHERE clause.
.
 The WHERE clause follows the FROM
The WHERE clause follows the FROM
clause
clause.
.
SELECT [DISTINCT] {*| column [alias], ...}
FROM table
[WHERE condition(s)];

Using the WHERE Clause
Using the WHERE Clause
SQL> SELECT ename, job, deptno
2 FROM emp
3 WHERE job='CLERK';
ENAME JOB DEPTNO
---------- --------- ---------
JAMES CLERK 30
SMITH CLERK 20
ADAMS CLERK 20
MILLER CLERK 10

Character Strings and Dates
Character Strings and Dates
 Character strings and date values are enclosed
Character strings and date values are enclosed
in single quotation marks
in single quotation marks.
.
 Character values are case sensitive and date
Character values are case sensitive and date
values are format sensitive
values are format sensitive.
.
 The default date format is DD
The default date format is DD-
-MON
MON-
-YY
YY.
.
SQL> SELECT ename, job, deptno
2 FROM emp
3 WHERE ename = ;
'JAMES'

Comparison Operators
Comparison Operators
Operator
=
>
>=
<
<=
<>, !=, ^=
Meaning
Equal to
Greater than
Greater than or equal to
Less than
Less than or equal to
Not equal to

Using the Comparison Operators
Using the Comparison Operators
SQL> SELECT ename, sal, comm
2 FROM emp
3 WHERE sal<=comm;
ENAME SAL COMM
---------- --------- ---------
MARTIN 1250 1400

Other Comparison Operators
Other Comparison Operators
Operator
BETWEEN
...AND...
IN(list)
LIKE
IS NULL
Meaning
Between two values (inclusive)
Match any of a list of values
Match a character pattern
Is a null value

Using the BETWEEN Operator
Using the BETWEEN Operator
ENAME SAL
---------- ---------
MARTIN 1250
TURNER 1500
WARD 1250
ADAMS 1100
MILLER 1300
SQL> SELECT ename, sal
2 FROM emp
3 WHERE sal BETWEEN 1000 AND 1500;
Lower
limit
Higher
limit
 Use the BETWEEN operator to display
Use the BETWEEN operator to display
rows based on a range of values
rows based on a range of values.
.

Using the IN Operator
Using the IN Operator
 Use the IN operator to test for values in a
Use the IN operator to test for values in a
list
list.
.
SQL> SELECT empno, ename, sal, mgr
2 FROM emp
3 WHERE mgr IN (7902, 7566, 7788);
EMPNO ENAME SAL MGR
--------- ---------- --------- ---------
7902 FORD 3000 7566
7369 SMITH 800 7902
7788 SCOTT 3000 7566
7876 ADAMS 1100 7788

Using the LIKE Operator
• Use the LIKE operator to perform
wildcard searches of valid search string
values.
• Search conditions can contain either
literal characters or numbers.
– % denotes zero or many characters.
– _ denotes one character.
SQL> SELECT ename
2 FROM emp
3 WHERE ename LIKE 'S%';

 You can combine pattern
You can combine pattern-
-matching characters
matching characters.
.
 You can use the ESCAPE identifier to search
You can use the ESCAPE identifier to search
for
for "%"
"%" or
or "
"_
_".
".
SQL> SELECT ename
2 FROM emp
3 WHERE ename LIKE '_A%';
ENAME
----------
MARTIN
JAMES
WARD

Using the IS NULL Operator
Using the IS NULL Operator
 Test for null values with the IS NULL
Test for null values with the IS NULL
operator
operator.
.
SQL> SELECT ename, mgr
2 FROM emp
3 WHERE mgr IS NULL;
ENAME MGR
---------- ---------
KING

Logical Operators
Logical Operators
Operator
AND
OR
NOT
Meaning
Returns TRUE if both component
conditions are TRUE
Returns TRUE if either component
condition is TRUE
Returns TRUE if the following
condition is FALSE

Using the AND Operator
Using the AND Operator
AND requires both conditions to be TRUE
AND requires both conditions to be TRUE.
.
SQL> SELECT empno, ename, job, sal
2 FROM emp
3 WHERE sal>=1100
4 AND job='CLERK';
EMPNO ENAME JOB SAL
--------- ---------- --------- ---------
7876 ADAMS CLERK 1100
7934 MILLER CLERK 1300

Using the OR Operator
Using the OR Operator
OR requires either condition to be TRUE
OR requires either condition to be TRUE.
.
SQL> SELECT empno, ename, job, sal
2 FROM emp
3 WHERE sal>=1100
4 OR job='CLERK';
EMPNO ENAME JOB SAL
--------- ---------- --------- ---------
7654 MARTIN SALESMAN 1250
...
7900 JAMES CLERK 950
...
14 rows selected.

Using the NOT Operator
Using the NOT Operator
SQL> SELECT ename, job
2 FROM emp
3 WHERE job NOT IN ('CLERK','MANAGER','ANALYST');
ENAME JOB
---------- ---------
KING PRESIDENT
MARTIN SALESMAN
ALLEN SALESMAN
TURNER SALESMAN
WARD SALESMAN

Rules of Precedence
Rules of Precedence
 Override rules of precedence by using
Override rules of precedence by using
parentheses
parentheses.
.
Order Evaluated Operator
1 All comparison
operators
2 NOT
3 AND
4 OR

Rules of Precedence
Rules of Precedence
ENAME JOB SAL
---------- --------- ---------
KING PRESIDENT 5000
MARTIN SALESMAN 1250
ALLEN SALESMAN 1600
TURNER SALESMAN 1500
WARD SALESMAN 1250
SQL> SELECT ename, job, sal
2 FROM emp
3 WHERE job='SALESMAN'
4 OR job='PRESIDENT'
5 AND sal>1500;

Rules of Precedence
Rules of Precedence
ENAME JOB SAL
---------- --------- ---------
KING PRESIDENT 5000
ALLEN SALESMAN 1600
Use parentheses to force priority
Use parentheses to force priority.
.
SQL> SELECT ename, job, sal
2 FROM emp
3 WHERE (job='SALESMAN'
4 OR job='PRESIDENT')
5 AND sal>1500;

ORDER BY Clause
ORDER BY Clause
 Sort rows with the ORDER BY clause
Sort rows with the ORDER BY clause
 ASC
ASC:
: ascending order, default
ascending order, default
 DESC
DESC:
: descending order
descending order
 The ORDER BY clause comes last in the
The ORDER BY clause comes last in the
SELECT statement
SELECT statement.
.
SQL> SELECT ename, job, deptno, hiredate
2 FROM emp
3 ORDER BY hiredate;
ENAME JOB DEPTNO HIREDATE
---------- --------- --------- ---------
SMITH CLERK 20 17-DEC-80
ALLEN SALESMAN 30 20-FEB-81
...
14 rows selected.

Sorting in Descending Order
Sorting in Descending Order
SQL> SELECT ename, job, deptno, hiredate
2 FROM emp
3 ORDER BY hiredate DESC;
ENAME JOB DEPTNO HIREDATE
---------- --------- --------- ---------
ADAMS CLERK 20 12-JAN-83
SCOTT ANALYST 20 09-DEC-82
MILLER CLERK 10 23-JAN-82
JAMES CLERK 30 03-DEC-81
FORD ANALYST 20 03-DEC-81
KING PRESIDENT 10 17-NOV-81
MARTIN SALESMAN 30 28-SEP-81
...
14 rows selected.

Sorting by Column Alias
Sorting by Column Alias
SQL> SELECT empno, ename, sal*12 annsal
2 FROM emp
3 ORDER BY annsal;
EMPNO ENAME ANNSAL
--------- ---------- ---------
7369 SMITH 9600
7900 JAMES 11400
7876 ADAMS 13200
7654 MARTIN 15000
7521 WARD 15000
7934 MILLER 15600
7844 TURNER 18000
...
14 rows selected.

Sorting by Multiple Columns
Sorting by Multiple Columns
 The order of ORDER BY list is the order of sort
The order of ORDER BY list is the order of sort.
.
• You can sort by a column that is not in the
SELECT list.
SQL> SELECT ename, deptno, sal
2 FROM emp
3 ORDER BY deptno, sal DESC;
ENAME DEPTNO SAL
---------- --------- ---------
KING 10 5000
CLARK 10 2450
MILLER 10 1300
FORD 20 3000
...
14 rows selected.

Summary
Summary
SELECT [DISTINCT] {*| column [alias], ...}
FROM table
[WHERE condition(s)]
[ORDER BY {column, expr, alias} [ASC|DESC]];

Practice Overview
Practice Overview
 Selecting data and changing the order of rows displayed
Selecting data and changing the order of rows displayed
 Restricting rows by using the WHERE clause
Restricting rows by using the WHERE clause
 Using the double quotation marks in column aliases
Using the double quotation marks in column aliases

Single
Single-
-Row Functions
Row Functions

Objectives
Objectives
:
 Describe various types of functions available
Describe various types of functions available
in SQL
in SQL
 Use character, number, and date functions in
Use character, number, and date functions in
SELECT statements
SELECT statements
 Describe the use of conversion functions
Describe the use of conversion functions

SQL Functions
SQL Functions
Function
Function
Input
Input
arg 1
arg 1
arg 2
arg 2
arg
arg n
n
Function
Function
performs action
performs action
Output
Output
Result
Result
value
value

Two Types of SQL Functions
Two Types of SQL Functions
Functions
Functions
Single
Single-
-row
row
functions
functions
Multiple
Multiple-
-row
row
functions
functions

Single
Single-
-Row Functions
Row Functions
 Manipulate data items
Manipulate data items
 Accept arguments and return one value
Accept arguments and return one value
 Act on each row returned
Act on each row returned
 Return one result per row
Return one result per row
 May modify the datatype
May modify the datatype
 Can be nested
Can be nested
function_name (column|expression, [arg1, arg2,...])

Single
Single-
-Row Functions
Row Functions
Conversion
Conversion
Character
Character
Number
Number
Date
Date
General
General
Single
Single-
-row
row
functions
functions

Character Functions
Character Functions
Character
Character
functions
functions
LOWER
LOWER
UPPER
UPPER
INITCAP
INITCAP
CONCAT
CONCAT
SUBSTR
SUBSTR
LENGTH
LENGTH
INSTR
INSTR
LPAD, RPAD
LPAD, RPAD
TRIM, LTRIM, RTRIM
TRIM, LTRIM, RTRIM
REPLACE
REPLACE
Case conversion
Case conversion
functions
functions
Character manipulation
Character manipulation
functions
functions

Character Functions
Character Functions
 CONCAT – joins 2 character strings
CONCAT – joins 2 character strings
 INITCAP – returns a string with the initial letter only uppercase
INITCAP – returns a string with the initial letter only uppercase
 LENGTH – returns the length of a string
LENGTH – returns the length of a string
 LPAD, RPAD – returns a string with a specific number of
LPAD, RPAD – returns a string with a specific number of
characters added on the left or right side
characters added on the left or right side
 LTRIM, RTRIM – returns a string with all instances of a specific
LTRIM, RTRIM – returns a string with all instances of a specific
character trimmed from the left or right side
character trimmed from the left or right side
 REPLACE – replaces all instances of a character with another
REPLACE – replaces all instances of a character with another
character
character
 UPPER/LOWER – returns a string in all upper/lower case
UPPER/LOWER – returns a string in all upper/lower case
letters
letters
 SUBSTR
SUBSTR
 INSTR
INSTR

Function Result
Case Conversion Functions
Case Conversion Functions
 Convert case for character strings
Convert case for character strings
LOWER('SQL Course')
UPPER('SQL Course')
INITCAP('SQL Course')
sql course
SQL COURSE
Sql Course

Using Case Conversion
Using Case Conversion
Functions
Functions
 Display the employee number, name, and
Display the employee number, name, and
department number for employee Blake
department number for employee Blake.
.
SQL> SELECT empno, ename, deptno
2 FROM emp
3 WHERE ename = 'blake';
no rows selected
no rows selected
EMPNO ENAME DEPTNO
--------- ---------- ---------
7698 BLAKE 30
SQL> SELECT empno, ename, deptno
2 FROM emp
3 WHERE ename = UPPER('blake');

CONCAT('Good', 'String')
SUBSTR('String',1,3)
LENGTH('String')
INSTR('String', 'r')
LPAD(sal,10,'*')
TRIM('S' FROM 'SSMITH')
GoodString
Str
6
3
******5000
MITH
Function Result
Character Manipulation
Character Manipulation
Functions
Functions
 Manipulate character strings
Manipulate character strings

Using the Character
Using the Character
Manipulation Functions
Manipulation Functions
SQL> SELECT ename, CONCAT (ename, job), LENGTH(ename),
2 INSTR(ename, 'A')
3 FROM emp
4 WHERE SUBSTR(job,1,5) = 'SALES';
ENAME CONCAT(ENAME,JOB) LENGTH(ENAME) INSTR(ENAME,'A')
---------- ------------------- ------------- ----------------
MARTIN MARTINSALESMAN 6 2
ALLEN ALLENSALESMAN 5 1
TURNER TURNERSALESMAN 6 0
WARD WARDSALESMAN 4 2

Number Functions
Number Functions
 ABS - absolute value
ABS - absolute value
 CEIL – rounds a number up to the next integer
CEIL – rounds a number up to the next integer
 FLOOR – rounds a number down to the previous
FLOOR – rounds a number down to the previous
integer
integer
 MOD – returns the remainder of a number and a
MOD – returns the remainder of a number and a
divisor
divisor
 POWER - raises a number to an exponent
POWER - raises a number to an exponent
 ROUND - rounds a number
ROUND - rounds a number
 SQRT – returns the square root of a value
SQRT – returns the square root of a value
 TRUNC - truncates a number to the nearest whole
TRUNC - truncates a number to the nearest whole
number
number

Number Functions
Number Functions
 ROUND
ROUND:
: Rounds value to specified
Rounds value to specified
decimal
decimal
ROUND
ROUND(
(45.926, 2
45.926, 2)
)
45.93
45.93
 TRUNC
TRUNC:
: Truncates value to specified
Truncates value to specified
decimal
decimal
TRUNC
TRUNC(
(45.926, 2
45.926, 2)
)
45.92
45.92
 MOD
MOD:
: Returns remainder of division
Returns remainder of division
MOD
MOD(
(1600, 300
1600, 300)
)

Using the ROUND Function
Using the ROUND Function
SQL> SELECT ROUND(45.923,2), ROUND(45.923,0),
2 ROUND(45.923,-1)
3 FROM DUAL;
ROUND(45.923,2) ROUND(45.923,0) ROUND(45.923,-1)
--------------- -------------- -----------------
45.92 46 50

SQL> SELECT TRUNC(45.923,2), TRUNC(45.923),
2 TRUNC(45.923,-1)
3 FROM DUAL;
TRUNC(45.923,2) TRUNC(45.923) TRUNC(45.923,-1)
--------------- ------------- ---------------
45.92 45 40
Using the TRUNC Function
Using the TRUNC Function

Using the MOD Function
Using the MOD Function
 Calculate the remainder of the ratio of
Calculate the remainder of the ratio of
salary to commission for all employees
salary to commission for all employees
whose job title is salesman
whose job title is salesman.
.
SQL> SELECT ename, sal, comm, MOD(sal, comm)
2 FROM emp
3 WHERE job = 'SALESMAN';
ENAME SAL COMM MOD(SAL,COMM)
---------- --------- --------- -------------
MARTIN 1250 1400 1250
ALLEN 1600 300 100
TURNER 1500 0 1500
WARD 1250 500 250

Working with Dates
Working with Dates
 Oracle stores dates in an internal numeric
Oracle stores dates in an internal numeric
format
format:
: century, year, month, day, hours,
century, year, month, day, hours,
minutes, seconds
minutes, seconds.
.
 The default date format is DD
The default date format is DD-
-MON
MON-
-YY
YY.
.
 SYSDATE is a function returning date and
SYSDATE is a function returning date and
time
time.
.
 DUAL is a dummy table used to view
DUAL is a dummy table used to view
SYSDATE
SYSDATE.
.

Arithmetic with Dates
Arithmetic with Dates
 Add or subtract a number to or from a date
Add or subtract a number to or from a date
for a resultant
for a resultant date
date value
value.
.
 Subtract two dates to find the
Subtract two dates to find the number
number of days
of days
between those dates
between those dates.
.
 Add
Add hours
hours to a date by dividing the number of
to a date by dividing the number of
hours by 24
hours by 24.
.

Date Arithmetic
Date Arithmetic
 To find a date that is a specific number of
To find a date that is a specific number of
days before or after a known date, add or
days before or after a known date, add or
subtract the number from the known date
subtract the number from the known date
 Example:
Example:
SELECT order_date + 30
SELECT order_date + 30
FROM cust_order;
FROM cust_order;

Date Arithmetic
Date Arithmetic
 To find the number of days between two
To find the number of days between two
known dates, subtract the later date from
known dates, subtract the later date from
the earlier date
the earlier date
 Example:
Example:
SELECT SYSDATE – s_dob
SELECT SYSDATE – s_dob
FROM my_students;
FROM my_students;

with Dates
with Dates
SQL> SELECT ename, (SYSDATE-hiredate)/7 WEEKS
2 FROM emp
3 WHERE deptno = 10;
ENAME WEEKS
---------- ---------
KING 830.93709
CLARK 853.93709
MILLER 821.36566

Date Functions
Date Functions
Number of months
between two dates
MONTHS_BETWEEN
ADD_MONTHS
NEXT_DAY
LAST_DAY
ROUND
TRUNC
Add calendar months to
date
Next day of the date
specified
Last day of the month
Round date
Truncate date
Function Description

• MONTHS_BETWEEN
MONTHS_BETWEEN (
('01-SEP-95','11-JAN-94'
'01-SEP-95','11-JAN-94')
)
Using Date Functions
• ADD_MONTHS
ADD_MONTHS (
('11-JAN-94',6
'11-JAN-94',6)
)
• NEXT_DAY
NEXT_DAY (
('01-SEP-95','FRIDAY'
'01-SEP-95','FRIDAY')
)
• LAST_DAY
LAST_DAY(
('01-SEP-95'
'01-SEP-95')
)
19.6774194
19.6774194
'11-JUL-94'
'11-JUL-94'
'08-SEP-95'
'08-SEP-95'
'30-SEP-95'
'30-SEP-95'

• ROUND
ROUND(
('25-JUL-95','MONTH'
'25-JUL-95','MONTH')
) 01-AUG-95
01-AUG-95
• ROUND
ROUND(
('25-JUL-95','YEAR'
'25-JUL-95','YEAR')
) 01-JAN-96
01-JAN-96
• TRUNC
TRUNC(
('25-JUL-95','MONTH'
'25-JUL-95','MONTH')
) 01-JUL-95
01-JUL-95
• TRUNC
TRUNC(
('25-JUL-95','YEAR'
'25-JUL-95','YEAR')
) 01-JAN-
01-JAN-
95
95

Date Functions
Date Functions
 ADD_MONTHS
ADD_MONTHS
 returns a date that is a specific number of months
returns a date that is a specific number of months
after a given date
after a given date
 Example:
Example:
SELECT ADD_MONTHS(SYSDATE, 6)
SELECT ADD_MONTHS(SYSDATE, 6)
FROM dual;
FROM dual;

Date Functions
Date Functions
 LAST_DATE
LAST_DATE
 Returns the date that is the last day of the month
Returns the date that is the last day of the month
specified in the current date
specified in the current date
 Example:
Example:
SELECT LAST_DATE(order_date)
SELECT LAST_DATE(order_date)
FROM cust_order
FROM cust_order
WHERE order_id = 1057;

Date Functions
Date Functions
 MONTHS_BETWEEN
MONTHS_BETWEEN
 Returns the number of months between two
Returns the number of months between two
input dates
input dates
 Example:
Example:
SELECT MONTHS_BETWEEN(order_date,
SELECT MONTHS_BETWEEN(order_date,
SYSDATE)
SYSDATE)
FROM cust_order
FROM cust_order

Conversion Functions
Conversion Functions
Implicit datatype
Implicit datatype
conversion
conversion
Explicit datatype
Explicit datatype
conversion
conversion
Datatype
Datatype
conversion
conversion

Implicit Datatype Conversion
 For assignments, the Oracle Server can
For assignments, the Oracle Server can
automatically convert the following
automatically convert the following:
:
VARCHAR2 or CHAR
From To
VARCHAR2 or CHAR
NUMBER
DATE
NUMBER
DATE
VARCHAR2
VARCHAR2

 For expression evaluation, the Oracle Server
For expression evaluation, the Oracle Server
can automatically convert the following
can automatically convert the following:
:
VARCHAR2 or CHAR
From To
VARCHAR2 or CHAR
NUMBER
DATE

Explicit Datatype Conversion
Explicit Datatype Conversion
NUMBER
NUMBER CHARACTER
CHARACTER
TO_CHAR
TO_CHAR
TO_NUMBER
TO_NUMBER
DATE
DATE
TO_CHAR
TO_CHAR
TO_DATE
TO_DATE

TO_CHAR Function with Dates
TO_CHAR Function with Dates
 The format model:
 Must be enclosed in single quotation marks and is
Must be enclosed in single quotation marks and is
case sensitive
case sensitive
 Can include any valid date format element
Can include any valid date format element
 Has an
Has an fm
fm element to remove padded blanks or
element to remove padded blanks or
suppress leading zeros
suppress leading zeros
 Is separated from the date value by a comma
Is separated from the date value by a comma
TO_CHAR(date, 'fmt')

YYYY
Elements of Date Format Model
YEAR
MM
MONTH
DY
DAY
Full year in numbers
Year spelled out
Two-digit value for month
Three-letter abbreviation of the
day of the week
Full name of the day
Full name of the month

Time elements format the time portion of
Time elements format the time portion of
the date
the date.
.
Add character strings by enclosing them in
Add character strings by enclosing them in
double quotation marks
double quotation marks.
.
Number suffixes spell out numbers
Number suffixes spell out numbers.
.
HH24:MI:SS AM 15:45:32 PM
DD "of" MONTH 12 of OCTOBER
ddspth fourteenth

Using TO_CHAR Function
with Dates
with Dates
SQL> SELECT ename,
2 TO_CHAR(hiredate, 'fmDD Month YYYY') HIREDATE
3 FROM emp;
ENAME HIREDATE
---------- -----------------
KING 17 November 1981
BLAKE 1 May 1981
CLARK 9 June 1981
JONES 2 April 1981
MARTIN 28 September 1981
ALLEN 20 February 1981
...
14 rows selected.

TO_CHAR Function with Numbers
TO_CHAR Function with Numbers
 Use these formats with the TO_CHAR function
Use these formats with the TO_CHAR function
to display a number value as a character
to display a number value as a character:
:
TO_CHAR(number, 'fmt')
9
0
$
L
.
,
Represents a number
Forces a zero to be displayed
Places a floating dollar sign
Uses the floating local currency symbol
Prints a decimal point
Prints a thousand indicator

with Numbers
with Numbers
SQL> SELECT TO_CHAR(sal,'$99,999') SALARY
2 FROM emp
3 WHERE ename = 'SCOTT';
SALARY
--------
$3,000

TO_NUMBER and
TO_NUMBER and
TO_DATE Functions
TO_DATE Functions
 Convert a character string to a number format
Convert a character string to a number format
using the
using the TO_NUMBER
TO_NUMBER function
function
TO_NUMBER(char[, 'fmt'])
• Convert a character string to a date
format using the TO_DATE function
TO_DATE(char[, 'fmt'])

NVL Function
NVL Function
 Converts null to an actual value
Converts null to an actual value
 Datatypes that can be used are date, character,
Datatypes that can be used are date, character,
and number
and number.
.
 Datatypes must match
Datatypes must match
 NVL
NVL(
(comm,0
comm,0)
)
 NVL
NVL(
(hiredate,'01-JAN-97'
hiredate,'01-JAN-97')
)
 NVL
NVL(
(job,'No Job Yet'
job,'No Job Yet')
)

SQL> SELECT ename, sal, comm, (sal*12)+NVL(comm,0)
2 FROM emp;
Using the NVL Function
ENAME SAL COMM (SAL*12)+NVL(COMM,0)
---------- --------- --------- --------------------
KING 5000 60000
BLAKE 2850 34200
CLARK 2450 29400
JONES 2975 35700
MARTIN 1250 1400 16400
ALLEN 1600 300 19500
...
14 rows selected.

Nesting Functions
Nesting Functions
 Single
Single-
-row functions can be nested to any level
row functions can be nested to any level.
.
 Nested functions are evaluated from deepest level to
Nested functions are evaluated from deepest level to
the least
the least-
-deep level
deep level.
.
F3(F2(F1(col,arg1),arg2),arg3)
Step 1 = Result 1
Step 2 = Result 2
Step 3 = Result 3

Nesting Functions
Nesting Functions
SQL> SELECT ename,
2 NVL(TO_CHAR(mgr),'No Manager')
3 FROM emp
4 WHERE mgr IS NULL;
ENAME NVL(TO_CHAR(MGR),'NOMANAGER')
---------- -----------------------------
KING No Manager

Summary
Summary
 Use functions to do the following
Use functions to do the following:
:
 Perform calculations on data
Perform calculations on data
 Modify individual data items
Modify individual data items
 Manipulate output for groups of rows
Manipulate output for groups of rows
 Alter date formats for display
Alter date formats for display
 Convert column datatypes
Convert column datatypes

Aggregating Data
Aggregating Data
Using Group Functions
(
(multiple row functions
multiple row functions)
)

Objectives
Objectives
:
 Identify the available group functions
Identify the available group functions
 Describe the use of group functions
Describe the use of group functions
 Group data using the GROUP BY clause
Group data using the GROUP BY clause
 Include or exclude grouped rows by using the
Include or exclude grouped rows by using the
HAVING clause
HAVING clause

What Are Group Functions?
What Are Group Functions?
 Group functions operate on sets of rows to give
Group functions operate on sets of rows to give
one result per group
one result per group.
.
EMP
EMP
“
“maximum
maximum
salary in
salary in
the EMP table”
the EMP table”
DEPTNO SAL
--------- ---------
10 2450
10 5000
10 1300
20 800
20 1100
20 3000
20 3000
20 2975
30 1600
30 2850
30 1250
30 950
30 1500
30 1250
MAX(SAL)
---------
5000

Types of Group Functions
Types of Group Functions
 AVG
AVG
 COUNT
COUNT
 COUNT(*)
COUNT(*)
 MAX
MAX
 MIN
MIN
 SUM
SUM

SELECT [column,] group_function(column)
FROM table
[WHERE condition]
[GROUP BY column]
[ORDER BY column];

Using AVG and SUM Functions
Using AVG and SUM Functions
AVG(SAL) MAX(SAL) MIN(SAL) SUM(SAL)
-------- --------- --------- ---------
1400 1600 1250 5600
 You can use AVG and SUM for numeric data
You can use AVG and SUM for numeric data.
.
SQL> SELECT AVG(sal), MAX(sal),
2 MIN(sal), SUM(sal)
3 FROM emp
4 WHERE job LIKE 'SALES%';

Using MIN and MAX Functions
Using MIN and MAX Functions
 You can use MIN and MAX for any datatype
You can use MIN and MAX for any datatype.
.
SQL> SELECT MIN(hiredate), MAX(hiredate)
2 FROM emp;
MIN(HIRED MAX(HIRED
--------- ---------
17-DEC-80 12-JAN-83

Using the COUNT Function
COUNT(*)
---------
6
SQL> SELECT COUNT(*)
2 FROM emp
 COUNT
COUNT(*)
(*) returns the number of rows in a
returns the number of rows in a
table
table.
.

 COUNT
COUNT(
(expr
expr)
) returns the number of
returns the number of
nonnull rows
nonnull rows.
.
SQL> SELECT COUNT(comm)
2 FROM emp
COUNT(COMM)
-----------
4

Group Functions and Null
Group Functions and Null
Values
Values
 Group functions ignore null values in the
Group functions ignore null values in the
column
column.
.
SQL> SELECT AVG(comm)
2 FROM emp;
AVG(COMM)
---------
550

with Group Functions
with Group Functions
 The NVL function forces group functions to
The NVL function forces group functions to
include null values
include null values.
.
SQL> SELECT AVG(NVL(comm,0))
2 FROM emp;
AVG(NVL(COMM,0))
----------------
157.14286

Creating Groups of Data
EMP
EMP
“
“average
average
salary
salary
in EMP
in EMP
table
table
for each
for each
department”
department”
2916.6667
2916.6667
2175
2175
1566.6667
1566.6667
DEPTNO SAL
--------- ---------
10 2450
10 5000
10 1300
20 800
20 1100
20 3000
20 3000
20 2975
30 1600
30 2850
30 1250
30 950
30 1500
30 1250
DEPTNO AVG(SAL)
------- ---------
10 2916.6667
20 2175
30 1566.6667

Creating Groups of Data:
:
GROUP BY Clause
GROUP BY Clause
SELECT column, group_function(column)
FROM table
[WHERE condition]
[GROUP BY group_by_expression]
[ORDER BY column];
 Divide rows in a table into smaller groups by
Divide rows in a table into smaller groups by
using the GROUP BY clause
using the GROUP BY clause.
.

Using the GROUP BY Clause
 All columns in the SELECT list that are not
All columns in the SELECT list that are not
in group functions must be in the GROUP
in group functions must be in the GROUP
BY clause
BY clause.
.
SQL> SELECT deptno, AVG(sal)
2 FROM emp
3 GROUP BY deptno;
DEPTNO AVG(SAL)
--------- ---------
10 2916.6667
20 2175
30 1566.6667

 The GROUP BY column does not have to
The GROUP BY column does not have to
be in the SELECT list
be in the SELECT list.
.
SQL> SELECT AVG(sal)
2 FROM emp
3 GROUP BY deptno;
AVG(SAL)
---------
2916.6667
2175
1566.6667

Grouping by More
Grouping by More
Than One Column
Than One Column
EMP
EMP
“
“sum salaries in
sum salaries in
the EMP table
the EMP table
for each job,
for each job,
grouped by
grouped by
department”
department”
DEPTNO JOB SAL
--------- --------- ---------
10 MANAGER 2450
10 PRESIDENT 5000
10 CLERK 1300
20 CLERK 800
20 CLERK 1100
20 ANALYST 3000
20 ANALYST 3000
20 MANAGER 2975
30 SALESMAN 1600
30 MANAGER 2850
30 SALESMAN 1250
30 CLERK 950
30 SALESMAN 1500
30 SALESMAN 1250
JOB SUM(SAL)
--------- ---------
CLERK 1300
MANAGER 2450
PRESIDENT 5000
ANALYST 6000
CLERK 1900
MANAGER 2975
CLERK 950
MANAGER 2850
SALESMAN 5600
DEPTNO
--------
10
10
10
20
20
20
30
30
30

on Multiple Columns
on Multiple Columns
SQL> SELECT deptno, job, sum(sal)
2 FROM emp
3 GROUP BY deptno, job;
DEPTNO JOB SUM(SAL)
--------- --------- ---------
10 CLERK 1300
10 MANAGER 2450
10 PRESIDENT 5000
20 ANALYST 6000
20 CLERK 1900
...
9 rows selected.

Illegal Queries
Illegal Queries
 Any column or expression in the SELECT
Any column or expression in the SELECT
list that is not an aggregate function must be
list that is not an aggregate function must be
in the GROUP BY clause
in the GROUP BY clause.
.
SQL> SELECT deptno, COUNT(ename)
2 FROM emp;
SELECT deptno, COUNT(ename)
*
ERROR at line 1:
ORA-00937: not a single-group group function
Column missing in the GROUP BY clause
Column missing in the GROUP BY clause

Illegal Queries
Illegal Queries
 You cannot use the WHERE clause to restrict groups
You cannot use the WHERE clause to restrict groups.
.
 You use the HAVING clause to restrict groups
You use the HAVING clause to restrict groups.
.
SQL> SELECT deptno, AVG(sal)
2 FROM emp
3 WHERE AVG(sal) > 2000
4 GROUP BY deptno;
WHERE AVG(sal) > 2000
*
ERROR at line 3:
ORA-00934: group function is not allowed here
Cannot use the WHERE clause
Cannot use the WHERE clause
to restrict groups
to restrict groups

Excluding Group Results
“
“maximum
maximum
salary
salary
per department
per department
greater than
greater than
$2900”
$2900”
EMP
EMP
5000
5000
3000
3000
2850
2850
DEPTNO SAL
--------- ---------
10 2450
10 5000
10 1300
20 800
20 1100
20 3000
20 3000
20 2975
30 1600
30 2850
30 1250
30 950
30 1500
30 1250
DEPTNO MAX(SAL)
--------- ---------
10 5000
20 3000

Excluding Group Results:
:
HAVING Clause
HAVING Clause
 Use the HAVING clause to restrict groups
Use the HAVING clause to restrict groups
 Rows are grouped
Rows are grouped.
.
 The group function is applied
The group function is applied.
.
 Groups matching the HAVING clause are
Groups matching the HAVING clause are
displayed
displayed.
.
SELECT column, group_function
FROM table
[WHERE condition]
[HAVING group_condition]
[ORDER BY column];

Using the HAVING Clause
SQL> SELECT deptno, max(sal)
2 FROM emp
3 GROUP BY deptno
4 HAVING max(sal)>2900;
DEPTNO MAX(SAL)
--------- ---------
10 5000
20 3000

SQL> SELECT job, SUM(sal) PAYROLL
2 FROM emp
3 WHERE job NOT LIKE 'SALES%'
4 GROUP BY job
6 ORDER BY SUM(sal);
JOB PAYROLL
--------- ---------
ANALYST 6000
MANAGER 8275
5 HAVING SUM(sal)>5000

Nesting Group Functions
Nesting Group Functions
SQL> SELECT max(avg(sal))
2 FROM emp
3 GROUP BY deptno;
MAX(AVG(SAL))
-------------
2916.6667
 Display the maximum average salary
Display the maximum average salary.
.

Summary
Summary
SELECT column, group_function(column)
FROM table
[WHERE condition]
[HAVING group_condition]
[ORDER BY column];
 Order of evaluation of the clauses
Order of evaluation of the clauses:
:
 WHERE clause
WHERE clause
 GROUP BY clause
GROUP BY clause
 HAVING clause
HAVING clause

Manipulating Data
Manipulating Data

Objectives
Objectives
:
 Describe each DML statement
Describe each DML statement
 Insert rows into a table
Insert rows into a table
 Update rows in a table
Update rows in a table
 Delete rows from a table
Delete rows from a table
 Control transactions
Control transactions

Data Manipulation Language
Data Manipulation Language
 A DML statement is executed when you
A DML statement is executed when you:
:
 Add new rows to a table
Add new rows to a table
 Modify existing rows in a table
Modify existing rows in a table
 Remove existing rows from a table
Remove existing rows from a table
 A
A transaction
transaction consists of a collection of DML
consists of a collection of DML
statements that form a logical unit of work
statements that form a logical unit of work.
.

Transactions
Transactions
 Transaction
Transaction: series of action queries that represent a logical unit
: series of action queries that represent a logical unit
of work
of work
 consisting of one or more SQL DML commands
consisting of one or more SQL DML commands
 INSERT, UPDATE, DELETE
INSERT, UPDATE, DELETE
 All transaction commands must succeed or none can succeed
All transaction commands must succeed or none can succeed
 User can commit (save) changes
User can commit (save) changes
 User can roll back (discard) changes
User can roll back (discard) changes
 Pending transaction
Pending transaction: a transaction waiting to be committed or
: a transaction waiting to be committed or
rolled back
rolled back
 Oracle DBMS locks records associated with pending transactions
Oracle DBMS locks records associated with pending transactions
 Other users cannot view or modify locked records
Other users cannot view or modify locked records

Adding a New Row to a Table
Adding a New Row to a Table
DEPT
DEPT
DEPTNO DNAME LOC
------ ---------- --------
20 RESEARCH DALLAS
30 SALES CHICAGO
New row
New row
50 DEVELOPMENT DETROIT
DEPT
DEPT
DEPTNO DNAME LOC
------ ---------- --------
20 RESEARCH DALLAS
30 SALES CHICAGO
“…
“…insert a new row
insert a new row
into DEPT table…”
into DEPT table…”

The INSERT Statement
The INSERT Statement
 Add new rows to a table by using the INSERT
Add new rows to a table by using the INSERT
statement
statement.
.
 Only one row is inserted at a time with this
Only one row is inserted at a time with this
syntax
syntax.
.
INSERT INTO table [(column [, column...])]
VALUES (value [, value...]);

Inserting New Rows
Inserting New Rows
 Insert a new row containing values for each
Insert a new row containing values for each
column
column.
.
 List values in the default order of the columns
List values in the default order of the columns
in the table
in the table.
.
 Optionally list the columns in the INSERT
Optionally list the columns in the INSERT
clause
clause.
.
 Enclose character and date values within single
Enclose character and date values within single
quotation marks
quotation marks.
.
SQL> INSERT INTO dept (deptno, dname, loc)
2 VALUES (50, 'DEVELOPMENT', 'DETROIT');
1 row created
1 row created.
.

Inserting Rows with Null Values
Inserting Rows with Null Values
 Implicit method
Implicit method:
: Omit the column from the
Omit the column from the
column list
column list.
.
SQL> INSERT INTO dept (deptno, dname )
2 VALUES (60, 'MIS');
1 row created
1 row created.
.
• Explicit method: Specify the NULL
keyword.
SQL> INSERT INTO dept
2 VALUES (70, 'FINANCE', NULL);
1 row created
1 row created.
.

Inserting Special Values
Inserting Special Values
 The SYSDATE function records the
The SYSDATE function records the
current date and time
current date and time.
.
SQL> INSERT INTO emp (empno, ename, job,
2 mgr, hiredate, sal, comm,
3 deptno)
4 VALUES (7196, 'GREEN', 'SALESMAN',
5 7782, SYSDATE, 2000, NULL,
6 10);
1 row created
1 row created.
.

Inserting Specific Date Values
Inserting Specific Date Values
 Add a new employee
Add a new employee.
.
SQL> INSERT INTO emp
2 VALUES (2296,'AROMANO','SALESMAN',7782,
3 TO_DATE('FEB 3, 1997', 'MON DD, YYYY'),
4 1300, NULL, 10);
1 row created
1 row created.
.
• Verify your addition.
EMPNO ENAME JOB MGR HIREDATE SAL COMM DEPTNO
----- ------- -------- ---- --------- ---- ---- ------
2296 AROMANO SALESMAN 7782 03-FEB-97 1300 10

Inserting Values by Using
Inserting Values by Using
Substitution Variables
Substitution Variables
 Create an interactive script by using SQL
Create an interactive script by using SQL*
*Plus
Plus
substitution parameters
substitution parameters.
.
SQL> INSERT INTO dept (deptno, dname, loc)
2 VALUES (&department_id,
3 '&department_name', '&location');
Enter value for department_id: 80
80
Enter value for department_name: EDUCATION
EDUCATION
Enter value for location: ATLANTA
ATLANTA
1 row created.

Creating a Script
Creating a Script
with Customized Prompts
with Customized Prompts
 ACCEPT stores the value in a variable
ACCEPT stores the value in a variable.
.
 PROMPT displays your customized text
PROMPT displays your customized text.
.
ACCEPT department_id PROMPT 'Please enter the -
department number:'
ACCEPT department_name PROMPT 'Please enter -
the department name:'
ACCEPT location PROMPT 'Please enter the -
location:'
INSERT INTO dept (deptno, dname, loc)
VALUES (&department_id, '&department_name',
'&location');

Copying Rows
Copying Rows
from Another Table
from Another Table
 Write your INSERT statement with a
Write your INSERT statement with a
subquery
subquery.
.
 Do not use the VALUES clause
Do not use the VALUES clause.
.
 Match the number of columns in the INSERT
Match the number of columns in the INSERT
clause to those in the subquery
clause to those in the subquery.
.
SQL> INSERT INTO managers(id, name, salary, hiredate)
2 SELECT empno, ename, sal, hiredate
3 FROM emp
4 WHERE job = 'MANAGER';
3 rows created
3 rows created.
.

Changing Data in a Table
Changing Data in a Table
EMP
EMP
“…
“…update a row
update a row
in EMP table…”
in EMP table…”
EMP
EMP
...
20
...

The UPDATE Statement
The UPDATE Statement
 Modify existing rows with the UPDATE
Modify existing rows with the UPDATE
statement
statement.
.
 Update more than one row at a time, if
Update more than one row at a time, if
required
required.
.
UPDATE table
SET column = value [, column = value, ...]
[WHERE condition];

Updating Rows in a Table
Updating Rows in a Table
 Specific row or rows are modified when you
Specific row or rows are modified when you
specify the WHERE clause
specify the WHERE clause.
.
 All rows in the table are modified if you omit
All rows in the table are modified if you omit
the WHERE clause
the WHERE clause.
.
SQL> UPDATE emp
2 SET deptno = 20
3 WHERE empno = 7782;
1 row updated
1 row updated.
.
SQL> UPDATE employee
2 SET deptno = 20;
14 rows updated
14 rows updated.
.

Updating with
Updating with
Multiple
Multiple-
-Column Subquery
Column Subquery
SQL> UPDATE emp
2 SET (job, deptno) =
3 (SELECT job, deptno
4 FROM emp
5 WHERE empno = 7499)
1 row updated
1 row updated.
.
 Update employee 7698’s job and department
Update employee 7698’s job and department
to match that of employee 7499
to match that of employee 7499.
.

Updating Rows Based
Updating Rows Based
on Another Table
on Another Table
 Use subqueries in UPDATE statements to
Use subqueries in UPDATE statements to
update rows in a table based on values from
update rows in a table based on values from
another table
another table.
.
SQL> UPDATE employee
2 SET deptno = (SELECT deptno
3 FROM emp
4 WHERE empno = 7788)
5 WHERE job = (SELECT job
6 FROM emp
7 WHERE empno = 7788);
2 rows updated
2 rows updated.
.

UPDATE emp
*
ERROR at line 1:
ORA-02291: integrity constraint (USR.EMP_DEPTNO_FK)
violated - parent key not found
SQL> UPDATE emp
2 SET deptno = 55
Updating Rows
Updating Rows:
:
Integrity Constraint Error
 Department number 55 does not exist
Department number 55 does not exist

“…
“…delete a row
delete a row
from DEPT table…”
from DEPT table…”
Removing a Row from a Table
Removing a Row from a Table
DEPT
DEPT
DEPTNO DNAME LOC
------ ---------- --------
20 RESEARCH DALLAS
30 SALES CHICAGO
60 MIS
...
DEPT
DEPT
DEPTNO DNAME LOC
------ ---------- --------
20 RESEARCH DALLAS
30 SALES CHICAGO
60 MIS
...

The DELETE Statement
The DELETE Statement
 You can remove existing rows from a table by
You can remove existing rows from a table by
using the DELETE statement
using the DELETE statement.
.
DELETE [FROM] table
[WHERE condition];

 Specific rows are deleted when you specify the
Specific rows are deleted when you specify the
WHERE clause
WHERE clause.
.
 All rows in the table are deleted if you omit
All rows in the table are deleted if you omit
the WHERE clause
the WHERE clause.
.
Deleting Rows from a Table
Deleting Rows from a Table
SQL> DELETE FROM department
2 WHERE dname = 'DEVELOPMENT';
1 row deleted
1 row deleted.
.
SQL> DELETE FROM department;
4 rows deleted
4 rows deleted.
.

Deleting Rows Based
Deleting Rows Based
on Another Table
on Another Table
 Use subqueries in DELETE statements to
Use subqueries in DELETE statements to
remove rows from a table based on values from
remove rows from a table based on values from
another table
another table.
.
SQL> DELETE FROM employee
2 WHERE deptno =
3 (SELECT deptno
4 FROM dept
5 WHERE dname ='SALES');
6 rows deleted
6 rows deleted.
.

Deleting Rows
Deleting Rows:
:
SQL> DELETE FROM dept
DELETE FROM dept
*
ERROR at line 1:
ORA-02292: integrity constraint (USR.EMP_DEPTNO_FK)
violated - child record found
You cannot delete a row
You cannot delete a row
that contains a primary key
that contains a primary key
that is used as a foreign key
that is used as a foreign key
in another table
in another table.
.

Database Transactions
 Consist of one of the following statements
Consist of one of the following statements:
:
 DML statements that make up one consistent
DML statements that make up one consistent
change to the data
change to the data
 One DDL statement
One DDL statement
 One DCL statement
One DCL statement

 Begin when the first executable SQL
Begin when the first executable SQL
statement is executed
statement is executed
 End with one of the following events
End with one of the following events:
:
 COMMIT or ROLLBACK is issued
COMMIT or ROLLBACK is issued
 DDL or DCL statement executes
DDL or DCL statement executes (
(automatic
automatic
commit
commit)
)
 User exits
User exits
 System crashes
System crashes

Advantages of COMMIT
Advantages of COMMIT
and ROLLBACK Statements
and ROLLBACK Statements
 Ensure data consistency
Ensure data consistency
 Preview data changes before making changes
Preview data changes before making changes
permanent
permanent
 Group logically related operations
Group logically related operations

DELETE
DELETE
Controlling Transactions
Controlling Transactions
 Transaction
Transaction
Savepoint A
Savepoint A
ROLLBACK to Savepoint B
ROLLBACK to Savepoint B
DELETE
DELETE
Savepoint B
Savepoint B
COMMIT
COMMIT
INSERT
INSERT
UPDATE
UPDATE
ROLLBACK to Savepoint A
ROLLBACK to Savepoint A
INSERT
INSERT
UPDATE
UPDATE
INSERT
INSERT
ROLLBACK
ROLLBACK
INSERT
INSERT

 An automatic commit occurs under the
An automatic commit occurs under the
following circumstances
following circumstances:
:
 DDL statement is issued
DDL statement is issued
 DCL statement is issued
DCL statement is issued
 Normal exit from SQL
Normal exit from SQL*
*Plus, without explicitly
Plus, without explicitly
issuing COMMIT or ROLLBACK
issuing COMMIT or ROLLBACK
 An automatic rollback occurs under an
An automatic rollback occurs under an
abnormal termination of SQL
abnormal termination of SQL*
*Plus or a
Plus or a
system failure
system failure.
.
Implicit Transaction Processing
Implicit Transaction Processing

State of the Data Before
State of the Data Before
COMMIT or ROLLBACK
COMMIT or ROLLBACK
 The previous state of the data can be recovered
The previous state of the data can be recovered.
.
 The current user can review the results of the DML
The current user can review the results of the DML
operations by using the SELECT statement
operations by using the SELECT statement.
.
 Other users
Other users cannot
cannot view the results of the DML
view the results of the DML
statements by the current user
statements by the current user.
.
 The affected rows are
The affected rows are locked
locked; other users cannot
; other users cannot
change the data within the affected rows
change the data within the affected rows.
.

State of the Data After COMMIT
State of the Data After COMMIT
 Data changes are made permanent in the
Data changes are made permanent in the
database
database.
.
 The previous state of the data is permanently lost
The previous state of the data is permanently lost.
.
 All users can view the results
All users can view the results.
.
 Locks on the affected rows are released; those
Locks on the affected rows are released; those
rows are available for other users to manipulate
rows are available for other users to manipulate.
.
 All savepoints are erased
All savepoints are erased.
.

Committing Data
Committing Data
SQL> UPDATE emp
2 SET deptno = 10
1 row updated
1 row updated.
.
 Make the changes
Make the changes.
.
• Commit the changes.
SQL> COMMIT;
Commit complete
Commit complete.
.

State of the Data After ROLLBACK
State of the Data After ROLLBACK
 Discard all pending changes by using the
Discard all pending changes by using the
ROLLBACK statement
ROLLBACK statement.
.
 Data changes are undone
Data changes are undone.
.
 Previous state of the data is restored
Previous state of the data is restored.
.
 Locks on the affected rows are released
Locks on the affected rows are released.
.
SQL> DELETE FROM employee;
14 rows deleted
14 rows deleted.
.
SQL> ROLLBACK;
Rollback complete
Rollback complete.
.

Rolling Back Changes
Rolling Back Changes
to a Marker
to a Marker
 Create a marker in a current transaction by using the
Create a marker in a current transaction by using the
SAVEPOINT statement
SAVEPOINT statement.
.
 Roll back to that marker by using the ROLLBACK
Roll back to that marker by using the ROLLBACK
TO SAVEPOINT statement
TO SAVEPOINT statement.
.
SQL> UPDATE...
SQL> SAVEPOINT update_done;
Savepoint created
Savepoint created.
.
SQL> INSERT...
SQL> ROLLBACK TO update_done;
Rollback complete
Rollback complete.
.

Truncating Tables
Truncating Tables
 Removes all table data without saving any
Removes all table data without saving any
rollback information
rollback information
 Advantage: fast way to delete table data
Advantage: fast way to delete table data
 Disadvantage: can’t be undone
Disadvantage: can’t be undone
 Syntax:
Syntax:
TRUNCATE TABLE
TRUNCATE TABLE tablename
tablename;
;

Summary
Summary
Description
Adds a new row to the table
Modifies existing rows in the table
Removes existing rows from the table
Makes all pending changes permanent
Allows a rollback to the savepoint marker
Discards all pending data changes
Statement
INSERT
UPDATE
DELETE
COMMIT
SAVEPOINT
ROLLBACK

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