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Using LogDump & RBA’s to Reposition a REPLICAT Process

When a REPLICAT process ABEND’s it can be dificult to pinpoint why, and trying to get over the error and allow the REPLICAT to continue can be tricky.

In this example, my source is an Oracle Linux 12c machine running EXTRACT, my target is a Windows Server 2016 machine running MSSQL/REPLICAT.

The Error:

In this example, we are presented with the following errors in the REPLCIAT report after it has ABENDED

2019-08-15 18:21:20  WARNING OGG-03014  Source column COLUMN_NAME has more characters than target column COLUMN_NAME can hold. Some source characters will not be mapped during conversion from source character set UTF-8 to target character set UTF-16.

2019-08-16 09:28:56  ERROR   OGG-01163  Bad column length (357) specified for column COLUMN_NAME in table TABLE.X, maximum allowable length is 255.

From the same report, we need to garner what RBA the fault occured at, you can see this here:

Last log location read:
     FILE:      C:GoldenGatedirdat/1p000003921
     SEQNO:     3921
     RBA:       4982061
     TIMESTAMP: 2019-08-16 09:28:53.053432
     EOF:       NO
     READERR:   0

With this information, open LogDump, prepare the application, and move to your RBA:

Logdump 1 > open C:GoldenGatedirdat/1p000003921 (use your filename here)
Logdump 2 > ghdr on
logdump 3 > detail on
logdump 4 > detail data
logdump 5 > ggstoken on
logdump 6 > ggstoken detail
logdump 7 > pos 4982061 (use your RBA here)

Read On… ->

dave / September 3, 2019 / Code, Oracle

OGG-00730 – No minimum Supplemental Logging is enabled

This issue was encountered whilst shipping an Oracle 12c schema to an MSSQL Server 2014 instance using OGG 12.3.

During the Change Data Capture configuration and EXTRACT setup and start processes, you may find your EXTRACT abends with:

OGG-00730  No minimum supplemental logging is enabled.

There are 2 reasons this may occur, the first is that you actually don’t have any supplemental logging enabled… The second is a documented Oracle bug, in which the GoldenGate process detects the presence of LOG DATA, but reports back on it incorrectly. Both scenarios are explained below.

CHECK TO SEE IF DATABASE LEVEL SUPPLEMENTAL LOGGING IS ENABLED OR NOT:

SQL> SELECT force_logging, supplemental_log_data_min FROM v$database;

FORCE_LOGGING             SUPPLEME
------------------------- --------
NO                        NO

SQL>

In this case, there is no logging, so OGG is correct. We can enable it with:

SQL> ALTER DATABASE ADD SUPPLEMENTAL LOG DATA;
Database altered.

Read On… ->

dave / July 27, 2018 / Code, Oracle

OGG-01194 – Oracle Golden Gate CHARSET mismatch

When entertaining the loathsome idea of shipping an established Oracle data set to MSSQL (SQL Server 2014, Oracle 12c, and OGG 12.3 in this case), you may run into an issue that presents itself in the following form in your EXTRACT report:

WARNING OGG-01194
EXTRACT task RINI9001 abended : Conversion from character set UTF-8 of source column <COLUMN_NAME> to character set windows-1252 of target column <COLUMN_NAME> failed because the source column contains a character 'ef 81 8a' at offset 123 that is not available in the target character set.

THE PROBLEM?:

Essentially, the issue is that you are trying to have your REPLICAT process convert Unicode data into a CHARSET where that Unicode character doesn’t exist. This is the default behaviour of REPLICAT, it will always try to convert source data charsets to the target machine native.

RESOLUTION:

This can be controlled with “SOURCECHARSET” parameter in your REPLICAT task param file. Specifically “SOURCECHARSET PASSTHRU”. Using this parameter will force REPLICAT to blindly import the source data and not try to convert it to the native charset of the target machine.

More information on SOURCECHARSET here

dave / July 26, 2018 / Code, Oracle