Up Up And Away !!

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UPPER

Syntax: upper(variable)

Parameters:
Variable à String/Date Type/Number Type/Character

Return Type
If the variable is String/Char type than it gets converted into upper case.
If the variable is Number Type/Date Type then it gets converted into String type(VARCHAR) without impacting its value.

Used Case:
(i) If Manager wants to fetch details of employee with same surname. SQL consider entities with different case as different entitles. So, by converting all in same case can fetch us required data.

SELECT FIRST_NAME, LAST_NAME, PHONE_NUMBER
FROM EMPLOYEES WHERE UPPER(FIRST_NAME) = 'JOHN';





(ii) In case manager wants the details of employees with same hire date and salary to be displayed. In this case, upper() could be used to convert number and date type in varchar so that comparison can be done with given value.

SELECT * FROM EMPLOYEES
WHERE UPPER(HIRE_DATE)='25-JUN-97' AND UPPER(SALARY)='4800';





Location: Buffalo, NY, USA

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