#22: Inserting Data Into LONG VARCHAR Columns
The maximum length of a string literal that can be inserted is limited to 254 characters.
To get around this limitation:
INSERT INTO your.table
COLUMNS (LONG_COLUMN,
other columns)
VALUES ('* 254 characters *',
other values);
UPDATE your.table SET LONG_COLUMN = LONG_COLUMN | | 'remaining chars' WHERE KEY_COLUMN = 'key value';