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Capabilities of SQL SELECT Statements

A SELECT statement retrieves information from the database. You can do the following:

Projection: You can use the projection capability in SQL to choose the columns in a table that
you want returned by your query. You can choose as few or as many columns of the table as
you require.

 Selection: You can use the selection capability in SQL to choose the rows in a table that you
want returned by a query. You can use various criteria to restrict the rows that you see.

Joining: You can use the join capability in SQL to bring together data that is stored in different
tables by creating a link between them. Here Link is nothing but joining tables.

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