Answer Detail: RE: What is a NULL value? What are the pros and cons ...

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Question: What is a NULL value? What are the pros and cons of using NULLS?

Answer: A NULL value takes up one byte of storage and indicates that a value is not present as opposed to a space or zero value. It's the DB2 equivalent of TBD on an organizational chart and often correctly portrays a business situation. Unfortunately, it requires extra coding for an application program to handle this situation.

September 09, 2007 08:55:29	#2
arijit.seth	Member Since: Visitor Total Comments: N/A
RE: What is a NULL value? What are the pros and cons ...
A NULL value is different from a blank or a zero A NULL value can be inserted into columns of any data type A NULL value will evaluate to NULL in any expression (e.g.NULL multiplied by 10 is NULL) If a column has a NULL value, Oracle ignores any UNIQUE, FOREIGN KEY, CHECK constraints that may be attached to the column.

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