Oracle Comparison Operators.

Preamble

Comparison operators are used in the WHERE sentence to determine which records to select. Here is a list of comparison statements that you can use in Oracle PL/SQL:

Consider examples of comparison operators that you can use in Oracle PL/SQL.

Example of an equality operator

In Oracle PL/SQL you can use the = operator to verify equality in a query.
For example, you can use an = operator:

SELECT *
FROM contacts
WHERE last_name = 'Bernard';

In this example, the SELECT operator returns all the rows from the contacts table where last_name equals Bernard.

Here is an example of the inequality operator <>, !=

In Oracle PL/SQL, you can use the <> or != operators. To check inequality in a query.

For example, we could check for inequality using the <> operator in the following way:

SELECT *
FROM contacts
WHERE last_name <> 'Bernard';

In this example, the SELECT operator will return all the rows from the contacts table where last_name does not equal Bernard.

Or you may also write this query using the != operator in the following way:

SELECT *
FROM contacts
WHERE last_name != 'Bernard';

Both these requests will return the same results.

An example of an operator larger than >

You can use the > operator in Oracle PL/SQL to check the expression “more than”.

SELECT *
FROM contacts
WHERE contact_id > 20;

In this example, the SELECT statement will return all rows from the contacts table where contact_id is greater than 20. Contact_id equal to 20 will not be included in the result set.

Example operator greater than or equal to >=

In Oracle PL/SQL you can use the >= operator to check the expression, “more or equal”.

SELECT *
FROM contacts
WHERE contact_id >= 20;

In this case, the contact id must be higher than or equal to 20 for the SELECT operator to retrieve all records from the contacts table. Therefore in an instance, the resultant set will have the contact id value of 20.

The example of the operator is less than <

You can use the < operator in Oracle PL/SQL to check the expression “less than”.

SELECT *
FROM contacts
WHERE contact_id < 150;

In this example, the SELECT operator will return all rows from the contacts table where contact_id is less than 150. contact_id equal to 150 will not be included in the resulting set.

The example of the operator is less than or equal to <=

In Oracle PL/SQL you can use the <= operator to check for an expression that is “less or equal”.

SELECT *
FROM contacts
WHERE contact_id <= 150;

In this case, the SELECT operator will provide a list of all contacts database rows with contact id values of 150 or less. Therefore, for instance, the 150th product id will be a part of the final set.

Comparison Operators (Introduction to Oracle SQL)

About Enteros

Enteros offers a patented database performance management SaaS platform. It proactively identifies root causes of complex business-impacting database scalability and performance issues across a growing number of clouds, RDBMS, NoSQL, and machine learning database platforms.