Sql Operators
1. Relational
Operators (>,>=, <, <=, < > or! = (not equal to))
2. Logical
Operators (AND, OR, NOT)
3. Special
Operators (IN, BETWEEN, LIKE and Is)
Queries using
Where Clause (Relational & Logical)
- List The Employees Belonging To The Department
20
- Select * from emp where deptno = 20 ;
- List the details of the employees who have
joined before the end of september 1981.
- Select * from emp where hiredate <=
’30-Sep-1981’ ;
Using Special
Operators
IN: The
IN operator is used to determine if a given value matches any value in a sub
query or in a list
Syntax : [ Not ] In <List of Values>
Examples :
Using In Operator
- select * from emp where empno in
(7369,7499,7788);
Between
The Between
operator is used to specify a
range of values. It retrieves the values by depending on the condition, on the
range of any column
Syntax : [ Not ] Between <Begin
Expression And End Expression>
Note : Unlike in
ordinary English, “Between” is an inclusive operator ie both
the values will be included in the range. The Not
Between is an Exclusion
operator
Examples :
Using Between Operator
- select * from emp where sal between 3000 and
5000;
- List the employees details whose salary is not
between 3000 and 5000
- select * from emp where not sal>=3000 and
sal<=5000;
Using Between
Operator
- select * from emp where sal not between 3000
and 5000;
Like
Operator
The Like
Operators is only used with Char and Varchar2 data types to match a pattern of
characters
It determines whether or not a given
character string matches the specified pattern.
A pattern can include regular
characters and wild card characters. During pattern matching regular characters
must exactly match the characters specified in the character string.
Oracle supports two types of wild
cards, they are
- _ (underscore) : Represents a Single Character
- % (Percentage): Represents Multiple Characters
syntax : [ Not ] Like < Pattern >
Note : This Like Operator can only be used with Varchar2 and Char data types only.
Examples :
- List the details of the employees whose names
starting letter is ‘S’
- select * from emp where ename like ‘S%’;
The special
operator “is” is used with
the key word “NULL” to locate Null Values
Is
Operator
This operator is used to find or
locate the Null values in the given column or expression
Examples :
1. List the details of the employees who are not Eligible for
Commission
- select * from emp where comm is NULL;
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