Using the LIKE Condition

Use the LIKE condition 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.

SELECT       first_name

FROM         employees

WHERE        first_name LIKE 'S%' ;

Using the IN Condition

Use the IN membership condition to test for values in a list:

SELECT employee_id, last_name, salary, manager_id

FROM   employees

WHERE  manager_id IN (100, 101, 201) ;

EMPLOYEE_ID	LAST_NAME	SALARY	MANAGER_ID
201	Edi	1000	100
202	Laki	2000	100
203	John	1500	101
204	Haan	3000	201

Using Comparison Conditions

SELECT last_name, salary

FROM   employees

WHERE  salary <= 3000 ;

Last_name	Salary
Edin	2400
John	2300

Using the BETWEEN Condition

Use the BETWEEN condition to display rows based on a range of values:

SELECT last_name, salary

FROM   employees

WHERE  salary BETWEEN 2500 AND 3500 ;

Last_name	Salary
Edin	2400
John	2300

Comparison Conditions

Operator	Meaning
=	Equal to
>	Greater than
>=	Greater than or equal to
<	Less than
<=	Less than or equal to
<>	Not equal to
BETWEEN ...AND...	Between two values (inclusive)
IN(set)	Match any of a list of values
LIKE	Match a character pattern
IS NULL	Is a null value

Character Strings and Dates

•      Character strings and date values are enclosed by single quotation marks.

•      Character values are case-sensitive, and date values are format-sensitive.

•      The default date format is DD-MON-RR.

•      SELECT last_name, job_id, department_id FROM   employees WHERE  last_name = 'Jenny' ;

Limiting the Rows That Are Selected

Restrict the rows that are returned by using the WHERE clause:

SELECT *|{[DISTINCT] column|expression [alias],...}

FROM   table

[WHERE condition(s)];

The WHERE clause follows the FROM clause.

SELECT employee_id, last_name, job_id, department_id

FROM   employees

WHERE  department_id = 80 ;

EMPLOYEE_ID	LAST_NAME	JOB_ID	DEPARTMENT_ID
1000	PARK	PP1	80
1001	LAKI	PP2	80