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isWritable vs isDefinatelyWritable

Galen Benson

Joined: Dec 06, 2004
Posts: 8
Can anyone explain to me the difference in the ResultSetMetaData class between the isWritable vs isDefinatelyWritable? I'm in a class and none of us can figure out what the specific differences are. We are using DB2.
Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 32811

Let's start with the API from the JavaDoc:
isDefinitelyWritable - Indicates whether a write on the designated column will definitely succeed.
isWritable - Indicates whether it is possible for a write on the designated column to succeed.

The difference has to do with database locks. For isDefinitelyWritable(), I must already have a write lock to guarantee that the write will succeed. For isWritable(), it is sufficient that nobody else has a write lock so it at least possible for the write to succeed. isWritable() is more like a method to check that a write will not definitely fail.

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