Using Operators in SQL Queries

SQL queries can be filtered further with:

• the WHERE keyword
• the BETWEEN and AND operators, and
• operators for working with numeric or date and time data types (for example, =, >, >=)

Retrieve data for login attempts made after 2022-05-09:

SELECT * FROM log_in_attempts WHERE login_date > '2022-05-09';

In this case, 125 attempts were made after that date.

Now, include 2022-05-09 in the query:

SELECT * FROM log_in_attempts WHERE login_date >= '2022-05-09';

That brings the number up to 165 attempts.

Now query attempts between dates:

SELECT * FROM log_in_attempts WHERE login_date BETWEEN '2022-05-09' AND '2022-05-11';

This returns a value of 123 attempts.

Next, check for login attempts at certain times. In this case, before 0700:

SELECT * FROM log_in_attempts WHERE login_time < '07:00:00';

Now check login attempts between 0600 and 0700:

SELECT * FROM log_in_attempts WHERE login_time BETWEEN '06:00:00' AND '07:00:00';

Query for login attempts with event_id greater than or equal to 100:

SELECT * FROM log_in_attempts WHERE event_id >= 100;

Narrow it down to return only login attempts with event_id between 100 and 150:

SELECT * FROM log_in_attempts WHERE event_id BETWEEN 100 AND 150;