Answer:
"Option b and Option d" is the correct option for this question.
Explanation:
In the database, datatype belongs to the information storage medium, which can hold a specific type of value. There are several data types, which is used in database like integer, character, series, floating-point and array numbers, and the rules, that give levels of security to information are known as a security constraints. It may be either developed as rules on integrity, mathematical formalism rules or schematic rules, and other choices were wrong which can be described as follows:
- In option a, The asserts, which is in any exchange in a database, should only modify the information, that is effected in acceptable ways is called consistency, that's why it is wrong.
- In option c, The validity and accuracy of the data in the database can not be ensured, that's why it is wrong.
Statement two and three is correct.
Statement 1 is incorrect. A relative reference changes when a formula is copied to another cell while Absolute references remain constant. However, it is safe to say that an absolute address can be preceded by a $ sign before both the row and the column values. It is designated by the addition of a dollar sign either before the column reference, the row reference, or both. Statement C is also correct. A mixed reference is a combination of relative and absolute reference and the formula (= A1 + $B$2) is an example of a mixed cell reference.
