[NIFI-4842] PutDatabaseRecord throws "stream has all ready been closed" with oracle default values

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: 1.5.0
• Component/s: Extensions
• Labels: database nifi oracle processor
• Environment: Oracle
• Flags: Patch
• Assignee: Unassigned
• Reporter: Nimrod Avni
• Created: 05/Feb/18 21:13
• Updated: 10/Jul/18 17:22
• Resolved: 10/Jul/18 17:20

Description

When inserting into an oracle database (using ojdbc7 as the driver),  

to a table with one of its fields has a default value, the putdatabaserecord processor throws "stream has already been closed" exception.

i explored the problem for quite, even going as far as taking the code and debugging it on my pc

after a little bit of time i figured out what the problem was. 

The problem occurs while getting the TableSchema from the database (line 1018)

the DataBaseMetaData .getColumns method returns a result set of the descriptions of all the columns of the table, including the defaultvalue, which comes as a LONG typed variable

when trying to create a ColumnDescription object from the result set it gets values such as the name of the column, datatype and default value

But duo to a low level oracle protocol flaw you cannot fetch  LONG typed columns from the database unless it comes before any of the other cloumns.

https://blog.jooq.org/2015/12/30/oracle-long-and-long-raw-causing-stream-has-already-been-closed-exception/

 

to fix this i just moved line number 1088 

final String defaultValue = resultSet.getString("COLUMN_DEF");

to one line before line 1082

final String columnName = resultSet.getString("COLUMN_NAME");

 

i know it's a weird problem, and even a weirder solution. 

I would appreciate it greatly if you could make this upgrade to the PutDatabaseRecord processor

Issue Links

• Blocked: NIFI-4279 PutDataBaseRecord and ConvertJSONToSQL stream has already been closed