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== Arithmetic Operators==

Arithmetic operators are used for mathematical computations.
Operator
Example
Usage
**
10**5
The exponentiation operator. 10**5 = 100,000.
*
2*3
The multiplication operator. 2 * 3 = 6.
/
6/2
The division operator. 6/2 = 3.
+
2+2
The addition operator. 2+2 = 4.
-
4-2
The subtraction operator. 4 -2 = 2.
-
-5
The negation operator.
+
+5
It complements the negation operator.
The basic arithmetic operators in action.



<source lang="sql">
SQL>
SQL> SET SERVEROUTPUT ON
SQL> BEGIN
2 DBMS_OUTPUT.PUT_LINE(4 * 2); --multiplication
3 DBMS_OUTPUT.PUT_LINE(24 / 3); --division
4 DBMS_OUTPUT.PUT_LINE(4 + 4); --addition
5 DBMS_OUTPUT.PUT_LINE(16 - 8); --subtraction
6 END;
7 /
8
8
8
8
PL/SQL procedure successfully completed.
SQL></source>

== Comparison Operators==

Comparison operators are used to compare one value or expression to another.
All comparison operators return a boolean result.
Operator
Example
Usage
=
IF A = B THEN
The equality operator.
<>
IF A <> B THEN
The inequality operator.
!=
IF A != B THEN
Another inequality operator, synonymous with <>.
~=
IF A ~= B THEN
Another inequality operator, synonymous with <>.
<
IF A 
IF A > B THEN
The greater than operator.
<=
IF A <= B THEN
The less than or equal to operator.
>=
IF A >= B THEN
The greater than or equal to operator.
LIKE
IF A LIKE B THEN
The pattern-matching operator.
BETWEEN
IF A BETWEEN B AND C THEN
Checks to see if a value lies within a specified range of values.
IN
IF A IN (B,C,D) THEN
Checks to see if a value lies within a specified list of values.
IS NULL
IF A IS NULL THEN
Checks to see if a value is null.

== Exponentiation==



<source lang="sql">
SQL>
SQL> SET SERVEROUTPUT ON
SQL> BEGIN
2 DBMS_OUTPUT.PUT_LINE(4 ** 2);
3 END;
4 /
16
PL/SQL procedure successfully completed.
SQL>
SQL></source>

== Logical Operators==

PL/SQL has three logical operators: AND, OR, and NOT.
The NOT operator is typically used to negate the result of a comparison expression.
The AND and OR operators are typically used to link together multiple comparisons.
The Syntax for the NOT Operator:



<source lang="sql">
NOT boolean_expression</source>

== Logical Operators in PL/SQL==

x
y
x AND y
x OR y
NOT x
True
True
True
True
False
True
False
False
True
False
False
True
False
True
True
False
False
False
False
True

== Operators==

PL/SQL operators are either unary or binary.
Binary operators act on two values.
An example of binary operators is the addition operator, which adds two numbers together.
Unary operators only operate on one value.
The negation operator is unary.
PL/SQL operators can be divided into the following categories:
<OL><LI>Arithmetic operators</LI><LI>Comparison operators</LI><LI>Logical operators</LI><LI>String operators</LI></OL>
23. 1. Operators
23. 1. 1.
Operators
23. 1. 2.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Thebasicarithmeticoperatorsinaction.htm">The basic arithmetic operators in action</a>
23. 1. 3.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/LogicalOperatorsinPLSQL.htm">Logical Operators in PL/SQL</a>
23. 1. 4.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/RunningAnonymousBlocksofCode.htm">Running Anonymous Blocks of Code</a>
23. 1. 5.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/ArithmeticOperators.htm">Arithmetic Operators</a>
23. 1. 6.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Exponentiation.htm">Exponentiation</a>
23. 1. 7.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Thenegationandidentityoperatorsinaction.htm">The negation and identity operators in action.</a>
23. 1. 8.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/ComparisonOperators.htm">Comparison Operators</a>
23. 1. 9.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/TheRelationalOperators.htm">The Relational Operators: =, <>, !=, ~=, <, >, <=, >=</a>
23. 1. 10.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/LogicalOperators.htm">Logical Operators</a>
23. 1. 11.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/StringOperators.htm">String Operators</a>
23. 1. 12.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/UseofComparisonOperatorswithStrings.htm">Use of Comparison Operators with Strings</a>

== Running Anonymous Blocks of Code==



<source lang="sql">
SQL>
SQL> set serveroutput on
SQL> declare
2 v_length NUMBER :=5.5;
3 v_width NUMBER :=3.5;
4 v_area NUMBER;
5 begin
6 v_area:=v_length*v_width;
7 DBMS_OUTPUT.put_line("Area:"||v_area);
8 end;
9 /
Area:19.25
PL/SQL procedure successfully completed.
SQL></source>

== String Operators==

PL/SQL has two operators specifically designed to operate only on character string data.
These are the LIKE operator and the concatenation (||) operator.
The Syntax for the Concatenation Operator:



<source lang="sql">
string_1 || string_2</source>

== The basic arithmetic operators in action==



<source lang="sql">
SQL>
SQL> SET ECHO ON
SQL> SET SERVEROUTPUT ON
SQL>
SQL> BEGIN
2 DBMS_OUTPUT.PUT_LINE(4 * 2); --multiplication
3 DBMS_OUTPUT.PUT_LINE(24 / 3); --division
4 DBMS_OUTPUT.PUT_LINE(4 + 4); --addition
5 DBMS_OUTPUT.PUT_LINE(16 - 8); --subtraction
6 END;
7 /
8
8
8
8
PL/SQL procedure successfully completed.
SQL>
SQL></source>

== The negation and identity operators in action.==



<source lang="sql">
SQL>
SQL> SET SERVEROUTPUT ON
SQL> DECLARE
2 x NUMBER;
3 BEGIN
4 DBMS_OUTPUT.PUT_LINE(-242.24);
5 x := 5;
6 DBMS_OUTPUT.PUT_LINE(-x);
7 x := -5;
8 DBMS_OUTPUT.PUT_LINE(-x);
9 DBMS_OUTPUT.PUT_LINE(+10);
10 DBMS_OUTPUT.PUT_LINE(+x);
11 END;
12 /
-242.24
-5
5
10
-5
PL/SQL procedure successfully completed.
SQL></source>

== The Relational Operators: =, <>, !=, ~=, <, >, <=, >===

String comparisons are case-sensitive.
String comparisons are dependent on the character set being used.
String comparisons are affected by the underlying datatype.
Comparing two values as CHAR strings might yield different results than the same values compared as VARCHAR2 strings.
It"s important to remember that Oracle dates contain a time component
True Expressions
False Expressions
5 = 5
5 = 3
"AAAA" = "AAAA"
"AAAA " = "AAAA"
5 != 3
5 <> 5
"AAAA " ~= "AAAA"
"AAAA" ~= "AAAA"
10 < 200
10.1 < 10.05
"Jeff" < "Jenny"
"jeff" < "Jeff"
TO_DATE("15-Nov-61" < "15-Nov-97")
TO_DATE("1-Jan-97" < "1-Jan-96")
10.1 <= 10.1
10 <= 20
"A" <= "B"
"B" <= "A"
TO_DATE("1-Jan-97") <= TO_DATE("1-Jan-97)
TO_DATE("15-Nov-61") <= TO_DATE("15-Nov-60)

== Use of Comparison Operators with Strings==

When using character strings in comparison expressions, the result depends on several things:
<OL><LI>Character set</LI><LI>Datatype</LI><LI>Case (upper versus lower)</LI></OL>
In the typical ASCII environment,
<OL><LI>all lowercase letters are actually greater than all uppercase letters,</LI><LI>digits are less than all letters, and</LI><LI>the other characters fall in various places depending on their corresponding ASCII codes.</LI></OL>
23. 1. Operators
23. 1. 1.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Operators.htm">Operators</a>
23. 1. 2.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Thebasicarithmeticoperatorsinaction.htm">The basic arithmetic operators in action</a>
23. 1. 3.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/LogicalOperatorsinPLSQL.htm">Logical Operators in PL/SQL</a>
23. 1. 4.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/RunningAnonymousBlocksofCode.htm">Running Anonymous Blocks of Code</a>
23. 1. 5.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/ArithmeticOperators.htm">Arithmetic Operators</a>
23. 1. 6.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Exponentiation.htm">Exponentiation</a>
23. 1. 7.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/Thenegationandidentityoperatorsinaction.htm">The negation and identity operators in action.</a>
23. 1. 8.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/ComparisonOperators.htm">Comparison Operators</a>
23. 1. 9.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/TheRelationalOperators.htm">The Relational Operators: =, <>, !=, ~=, <, >, <=, >=</a>
23. 1. 10.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/LogicalOperators.htm">Logical Operators</a>
23. 1. 11.
<A href="/Tutorial/Oracle/0460__PL-SQL-Operators/StringOperators.htm">String Operators</a>
23. 1. 12.
Use of Comparison Operators with Strings

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