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What are the problems if one were not to normalize? When do these problems surface?
Ans: Database normalization, sometimes considered to as canonical synthesis, is a method for designing relational database tables to minimize duplication of information and, in so doing, to preserve the database against specific types of logical or structural problems, that are data anomalies. For instance, when multiple instances of a given piece of information take place in a table, the possibility exists that these examples will not be kept consistent while the data within the table is updated, leading to a loss of data integrity. A table that is adequately normalized is less vulnerable to problems of this type, as its structure reflects the basic assumptions for while multiple instances of similar information should be denoted by a single instance only.
The First Normal Form (1NF) Let us first describe 1NF: Definition: A relation (table) is in 1NF if 1. There are no duplicate tuples or rows in the relation. 2.
It defines that the tuple in one relation that refers to another relation must refer to an existing tuple in that relation. This constraint is states on two relations (not essentia
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let us consider a table having 2200 records and the fixed size of the table to be considered as 25.then how many numbers of table is requredto perform horizontal fragmentation
Load sample data into the database tables design and test queries to return the following information • All rows and columns for employees • All rows and columns for customers •
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Differentiate between static hashing and dynamic hashing. Ans: Static Hashing comprises the number of primary pages in the directory fixed. So, while a bucket is full, we requ
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