Set - 1

Question 21 :

Data types

Answer :

Max. columns in a table is 255. Max. Char size is 255, Long is 64K & Number is 38 digits.
Cannot Query on a long column.
Char, Varchar2 Max. size is 2000 & default is 1 byte.
Number(p,s) p is precision range 1 to 38, s is scale -84 to 127.
Long Character data of variable length upto 2GB.
Date Range from Jan 4712 BC to Dec 4712 AD.
Raw Stores Binary data (Graphics Image & Digitized Sound). Max. is 255 bytes.
Mslabel Binary format of an OS label. Used primarily with Trusted Oracle.

Question 22 :

Order of SQL statement execution

Answer :

Where clause, Group By clause, Having clause, Order By clause & Select.

Question 23 :


Answer :

Transaction is defined as all changes made to the database between successive commits.

Question 24 :


Answer :

Commit is an event that attempts to make data in the database identical to the data in the form. It involves writing or posting data to the database and committing data to the database. Forms check the validity of the data in fields and records during a commit. Validity check are uniqueness, consistency and db restrictions.

Question 25 :


Answer :

Posting is an event that writes Inserts, Updates & Deletes in the forms to the database but not committing these transactions to the database.