Reading BLOBS/CLOBS requires SQL "SELECT ... FOR UPDATE"
When a GsOracleConnection is configured to return GsOracleBLOB/CLOB objects (lobLimit > 0), the SQL SELECT statement used in the #openCursorOn: call to retrieve them has to include the suffix "FOR UPDATE", even if the application won't be writing the BLOB/CLOB. For example:
stream := myConnection openCursorOn: 'select clob_column from mytable for update'.
Failure to do so will result in the Oracle error:
ORA-22292: Cannot open a LOB in read-write mode without a transaction.
Workaround
Include "FOR UPDATE" in the SQL SELECT statement used for retrieving the BLOB/CLOB.
Last updated: 7/2/18