a2zinterviews

36.	What is bind reference and how can it be created?
	Bind reference are used to replace the single value in sql, pl/sql statements a bind reference can be created using a (:) before a column or a parameter name.

37.	How many LONG columns are allowed in a table? Is it possible to use LONG columns in WHERE clause or ORDER BY?
	Only one LONG column is allowed. It is not possible to use LONG column in WHERE or ORDER BY clause.

38.	What are various types of joins?
	Equi joins Cartesian joins Self join Outer join

39.	What is the maximum number of triggers, can apply to a single table?
	12 triggers

40.	What command would you use to create a backup control file?
	Alter database backup control file to trace.