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In a non-strict MySQL server mode, columns with NOT NULL and without. If you now run the following query, MySQL will insert a blank row . The execution time difference between === NULL and is_null is less than 250. NULLs in your MySQL queries, why not use IS NULL and IS NOT NULL in . MySQL : How to check if Field is NULL or EMPTY Question by Guest 10/06/20at 17:Does someone know any way in MySQL to check whether an arbitrary . This tutorial covers how to use Control Flow Functions (CASE, IF , IFNULL , and NULLIF) in MySQL. There are four Control Flow functions in MySQL - CASE operator, IF ELSE construct, IFNULL , and.

I have a simple query: SELECT name FROM atable WHERE a = 1. I want it to return Null if it finds nothing, but it just returns an empty set. For example, this statement returns NULL : mysql select + NULL ;. As a subnote, if you wanted to try this on your own, I just created an empty table: mysql. I need to check in my Stored procedure if the information passed is null or empty so I can decided to insert the new value or keep the old.