use HR
--CAST FONKSİYONU--

SELECT LAST_NAME, DATEDIFF(YEAR, HIRE_DATE,GETDATE()) AS WEEKS  -- TARİH ARALIĞINDAKİLERİ GETİR
FROM EMPLOYEES
WHERE DEPARTMENT_ID=90

SELECT CONVERT (INT,(CONVERT(FLOAT, '6.7',0))) -- DÖNÜŞTÜRÜR 


SELECT LAST_NAME, UPPER(CONCAT(SUBSTRING (LAST_NAME,1,8),'_US')) FROM EMPLOYEES WHERE DEPARTMENT_ID=60-- AL BUYUT EKLE

SELECT LAST_NAME,FIRST_NAME, ISNULL(CONVERT(NVARCHAR,COMMISSION_PCT),'BOS') FROM EMPLOYEES -- NULL OLANLARI BOS  İLE DĞEİŞTİR KOMUTU