我有一个数据库（某些数据库）的表（exp）超过800条记录，我想将列名从“ Nr._CRT”更改为“ ID”，并保持类型smallint。 错误是：

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '._CRT to ID' at line 1

到目前为止，我已经尝试了以下方法

    ALTER TABLE exp change Nr._CRT ID ;
    ALTER TABLE exp change 'Nr._CRT' 'ID' ;
    ALTER TABLE exp RENAME COLUMN Nr._CRT TO ID;
    ALTER TABLE exp RENAME COLUMN 'Nr._CRT' TO 'ID';
    ALTER TABLE exp CHANGE Nr._CRT ID ;
    ALTER TABLE exp CHANGE 'Nr._CRT' 'ID' ;
    ALTER TABLE exp RENAME COLUMN Nr._CRT TO ID;
    ALTER TABLE exp RENAME COLUMN 'Nr._CRT' TO 'ID';

请帮助...