How does Oracle SELECT query work?

How does SQL SELECT query work?

SQL Query mainly works in three phases .11) Row filtering - Phase 1: Row filtering - phase 1 are done by FROM, WHERE , GROUP BY , HAVING clause.22) Column filtering: Columns are filtered by SELECT clause.33) Row filtering - Phase 2: Row filtering - phase 2 are done by DISTINCT , ORDER BY , LIMIT clause.

How does database SELECT work?

The SQL SELECT statement returns a result set of records, from one or more tables. A SELECT statement retrieves zero or more rows from one or more database tables or database views. In most applications, SELECT is the most commonly used data manipulation language (DML) command.

What does a SELECT query do?

A select query helps you retrieve only the data that you want, and also helps you combine data from several data sources. You can use tables and other select queries as data sources for a select query.

What is SELECT query example?

The SELECT TOP statement is used to limit the number of rows which returns the result of the query. For example, if want to retrieve only two rows from the table we can use the following query. Therefore, we can limit the result set of the query. In the following SQL examples, we will limit the result set of the query.