使用php更新mysql表时如何添加许多WHERE约束？

Question

How can I add multiple constraints after the WHERE part of the UPDATE MySQL table statement? Is this possible? I have tried separating the constraints using commas. Thank you.

    $update_error = mysqli_query($con, "UPDATE users SET error_level='3'
                    WHERE errors <= '650', errors > '200'");

Answer 1

You should add logical operator (https://dev.mysql.com/doc/refman/5.7/en/logical-operators.html) which will describe to MYSQL what is the connection between conditions:

It will look like this

mysqli_query($con, "UPDATE users SET error_level='3' WHERE errors <= '650' AND errors > '200'");

or this

mysqli_query($con, "UPDATE users SET error_level='3' WHERE errors <= '650' OR errors > '200'");