SQL Index

While executing SQL query, most important aspect to consider is performance.  So  how you achieve a good performance from database queries. Let us take the example of a book. To find any topic in a book we don’t need to reference every page of book. We refer to index and…

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Where Vs Having Clause in SQL

While working with SQL, one of the question which often creates confusion is whether to use where or having clause.Though it appears that both clauses do the same thing, they do it in different ways.Here in this article, I will try to highlight all the major differences between WHERE and…

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SQL – Select Statement

Select statement is a DML (Data Manipulation Language) statement.The SELECT statement is an SQL statement that specifies which rows and columns to fetch from one or more tables or views. The SELECT statement is very helpful in finding filtered records from a database.

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SQL Join

A SQL Join clause is used to combine rows from two or more tables, views, or materialized views based on a common field between them. A SQL join condition is used in the where clause of select, update, delete statements.

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