Oracle-sql-cheat-sheet.md

Working with dates

-- now, timestamp
SELECT SYSDATE FROM dual

-- yesterday
SELECT SYSDATE - 1 FROM dual

-- truncated date (without timestamp)
SELECT TRUNC(SYSDATE) FROM dual

-- extract date part
SELECT SYSDATE, TO_DATE(SYSDATE) FROM dual

-- extract year from date
SELECT EXTRACT(YEAR FROM SYSDATE) FROM dual

-- format string to date
SELECT TO_DATE('2014-12-01', 'YYYY-MM-DD') FROM dual

Working with numbers

-- rounds to 1.23
SELECT ROUND(1.234, 2) FROM DUAL

-- rounds to 1.2
SELECT ROUND(1.234, 1) FROM DUAL

Misc

-- select top 10 rows
SELECT * FROM dual WHERE ROWNUM < 10