我正在尝试在SELECT语句中创建一个NULL列,但它不起作用:
错误代码为:
SELECT mytable. *, NULL as ColumnName
FROM mytable;
错误代码为:
Error report -
SQL Error: ORA-01723: zero-length columns are not allowed
01723. 00000 - "zero-length columns are not allowed"
*Cause: Columns with zero length were not allowed.
*Action: Correct the use of the column.
看起来似乎不可能做到。在SELECT语句中有创建一个NULL列的选择吗?
谢谢。