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What is a view in SQL Server ? How to create one.

What is Identity in SQL Server?

What are the differences between DDL, DML and DCL in SQL?

What is database normalization?

What is SQL?

What is the difference between primary key and unique constraints?

A super key is a set of attributes of a relation schema upon which all attributes of the schema are functionally dependent. No two rows can have the same value of super key attributes.  A Candidate key is minimal super key, i.e., no proper subset of Candidate key attributes can be a super key. A …

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What is the difference between a “Local Temporary Table” and “Global Temporary Table”?

1. We can have only one Primary Key in a table whereas we can have more than one Unique Key in a table.2. The Primary Key cannot have a NULL value whereas a Unique Key may have only one null value.3. By default, a Primary Key is a Clustered Index whereas by default, a Unique …

What is the difference between “Primary Key” and “Unique Key”? Read More »

1. WHERE clause can be used with a Select, Update and Delete Statement Clause but the HAVING clause can be used only with a Select statement.2. We can’t use an aggregate functions in the WHERE clause unless it is in a sub-query contained in a HAVING clause whereas we can use an aggregate function in …

What is the difference between the “WHERE” clause and the “HAVING” clause? Read More »