Why is MySQL assessment (TRUE or TRUE and FALSE) TRUE?

By Mysql

If you enter 

SELECT (true or true and false)

In mysql, It will return 1, which is true. Why is this happening? What is the order of evaluation in Boolean expressions?

According to the MySQL documentation on operator precedence, AND is evaluated before OR. This means your expression The formula (true or true and false) is calculated as (true OR(true AND false)).

If you enter

< pre>SELECT (true or true and false)

In mysql, it will return 1, which is true. Why is this? What is the order of evaluation in Boolean expressions?

According to the MySQL documentation on operator precedence, AND is evaluated before OR. This means that your expression (true or true and false) is calculated as ( true OR(true AND false)).

, , , ,

WordPress database error: [Table 'yf99682.wp_s6mz6tyggq_comments' doesn't exist]
SELECT SQL_CALC_FOUND_ROWS wp_s6mz6tyggq_comments.comment_ID FROM wp_s6mz6tyggq_comments WHERE ( comment_approved = '1' ) AND comment_post_ID = 2989 ORDER BY wp_s6mz6tyggq_comments.comment_date_gmt ASC, wp_s6mz6tyggq_comments.comment_ID ASC

Leave a Comment

Your email address will not be published.