You should use IS NOT NULL . (The comparison operators = and <> both give UNKNOWN with NULL on either side of the expression.) ... <看更多>

The PRIMARY KEY column(s) will become NOT NULL. If you subsequently use SHOW CREATE TABLE or DESCRIBE, you will see that this column property is ... ... <看更多>

What is Not null constraint in MySQL, Not Null Constraint My MariaDB Database explains with explain what is Not NULL constraint and how to ... ... <看更多>

If JavaScript null is passed and converted to MySQL NULL, then the mysql module should process it like a regular SQL query that has NULL value ... ... <看更多>