LEARNING PHP AND MYSQL (2015)

Operator	Description	Example
=	Equal to	John = ‘author’
<>	Not equal to	Dept<>height
>	Greater than	100>6
<	Less than	6<100
≥	Greater than or equal	Rate≥2.6
≤	Less than or equal	Rate ≤2.6
BETWEEN	In an inclusive range	Range BETWEEN 10 AND 20
LIKE	Match the character	NAME LIKE ‘WILLY%’
IS OR IS NOT	Compare to null	AGE IS OR IS NOT RAJ
IN	Equal to one of the multiple possible value	ID IN (100,120,134)
AS	Used to change name when viewing the result or the particular value	Select student AS ‘section a’
IS NOT DISTINCT FORM	Equal to value given or both are missing data	Loan IS NOT DISTINCT FORM-APPLICABLE

Conditions

SQL expression-

Case- It is one of the searching techniques of finding the matching case. It was used in SQL-92.

Example

CASE WHEN N > 0

THEN ‘POSITIVE VALUE’

WHEN<0

THEN ‘NEGATIVE VALUE’

ELSE

‘ZERO’

When- This condition is the source through which the data is compared with the output which is set is similar to its condition. That time the action which has to be take is defined using when the condition with the when statement is stated.

Example

CASE a

WHEN 1

THEN ‘ONE ORANGE’

WHEN 2

THEN ‘TWO ORANGES’

ELSE

‘CANNOT COUNT THAT VALUE’

Then- This statement is used to execute particular value or display particular value when the condition in WHEN statement is satisfied.

Example

CASE b

WHEN 3

THEN ‘three ORANGE’

WHEN 4

THEN ‘four ORANGES’

ELSE

‘CANNOT COUNT THAT VALUE’.

Else- When the when condition is not satisfied the process leads to another option, that is defined as else statement.

Example

WHEN 5

THEN ‘FIVE ORANGES’

ELSE

‘CANNOT COUNT THAT VALUE’.

End- It is used to terminate the program which leads the system to stop the execution.

Example

CASE x

WHEN 1

THEN ‘COUNT 1’

WHEN 2

THEN ‘COUNT 2’

ELSE ‘ERROR’

END