You want the following: ALTER TABLE mytable MODIFY mycolumn VARCHAR(255);. Columns are nullable by default. As long as the column is not ... ... <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 ... ... <看更多>

It actually doesn't accept NULL values it considers it as empty string. That's because you have your server in non-strict mode. That controls how MySQL ... ... <看更多>

MySQL NULL VALUE. NULL值是在新增資料時沒有設定欄位值，資料庫管理系統便設定該欄位的內容為NULL. 無法使用; 無法指派; 無法運算; 與0和空白不相同 ... ... <看更多>