100 + SQL and PL/SQL Tips
1. Zero is a number and a Space is a character.
2. Character strings and date values are enclosed in single quotation marks.
3. Character values are case sensitive and date values are format sensitive.
4. The default date format is DD-MON-RR. Oracle database stores date in a format: Century, year, month, day, hours, minutes and seconds.
5. An Alias cannot be used in the WHERE clause.
6. The symbol ! = and ^= also represents to not equal to condition.
7. Values specified with the BETWEEN condition are inclusive.
8. The IN condition is also called membership condition.
9. The IN condition can be used with any data type.
10. A NULL value cannot be equal (=) or unequal to any value.
11. NULL values are displayed last for ascending sequences and first for descending