问题
Why is long an issue with Oracle?
It will be better if some one can tell me what are the issues with using the long data type in oracle? something related to storage?
I was asked this in an interview.
回答1:
LONG is archaic and deprecated, and has been superseded by CLOB. There are lots of restrictions with LONGs and they are difficult to manipulate in SQL. So while you may have to deal with them in old databases, you would be unwise to ever use a LONG column in a new table.
回答2:
Unfortunately, LONGs are still sometimes necessary. For example, you can read a LONG from a remote database, but you can't read a CLOB from a remote database until 12.2. (Although you can always write a CLOB to a remote database.) I'm guessing this is why they are still used everywhere in the data dictionary.
Other than that issue, you should probably always use CLOBs.
来源：https://stackoverflow.com/questions/3386172/why-is-long-an-issue-with-oracle