In Oracle no string can exceed 4000 bytes (4000 ASCII/UTF-8 characters or 2000 UTF-16
characters). That's probably four times higher than I'd allow. If you have strings that could
stretch two gigabytes in length, they are not strings, they're documents. Documents are
stored in LOBs (CLOB for UTF-8, NCLOB for UTF-16). When LOBs are tossed around, you
wind up needing several copies of the bytestream as it propagates into the database.
Your 2Gb doc could easily use 4-18Gb of RAM each time it was touched, but it could only
do so if you raised the default limits on document size of 1-4Mb.
The error message you specified is an Oracle one, but should only occur when the app
and database disagree on datatypes, which makes me wonder if you've been editing the
table schema outside of ArcGIS' ken.
- V