Deletion anomaly if sid 401 has only one subject and

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there, leading to Insertion Anomaly. Deletion Anomaly : If (S_id) 401 has only one subject and temporarily he drops it, when we delete that row, entire student record will be deleted along with it.
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Normalization Rule Normalization rule are divided into following normal form. First Normal Form Second Normal Form Third Normal Form
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First Normal Form (1NF) Ruls: No two Rows of data must contain repeating group of information i.e each set of column must have a unique value, such that multiple columns cannot be used to fetch the same row ( It should hold only atomic values) Each table should be organized into rows, and each row should have a primary key that distinguishes it as unique.
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Example Is it in 1 NF?
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What is a KEY? A KEY is a value used to identify a record in a table uniquely. A KEY could be a single column or combination of multiple columns Note: Columns in a table that are NOT used to identify a record uniquely are called non-key columns.
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What is a Primary Key? A primary is a single column value used to identify a database record uniquely. It has following attributes A primary key cannot be NULL A primary key value must be unique The primary key values cannot be changed The primary key must be given a value when a new record is inserted.
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What is Composite Key and Foreign Key?
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