SharePlex 9.2.8 - Installation and Setup for Oracle Source

Set up replication from Oracle to Kafka

Overview

The SharePlex Post process can connect and write to a Kafka broker. The data can be written in JSON or XML output as a sequential series of operations as they occurred on the source, which can then be consumed by a Kafka consumer.

These instructions contain setup instructions that are specific to this target. Install SharePlex on the source and target according to the appropriate directions in this manual before performing these setup steps.

For the versions, data types and operations that are supported when using SharePlex to replicate to this target, see the SharePlex Release Notes.

Guidelines for posting to Kafka

• A SharePlex Post process acts as a Kafka producer. A SharePlex Post process can write to one or more topics that have one or more partitions.
• The SharePlex Post process does not create a topic itself, but you can configure the Kafka broker to auto-create topics.

Configure SharePlex on the source

When replicating data to Kafka, configure the source database and SharePlex on the source system as follows.

Enable supplemental logging

On the source system, enable PK/UK supplemental logging in the Oracle source database. SharePlex must have the Oracle key information to build an appropriate key on the target.

SQL> ALTER DATABASE ADD SUPPLEMENTAL LOG DATA (PRIMARY KEY, UNIQUE) COLUMNS;

Set SP_OCT_USE_SUPP_KEYS parameter

On the source system, set the SP_OCT_USE_SUPP_KEYS parameter to a value of 1. This parameter directs SharePlex to use the columns set by Oracle's supplemental logging as the key columns when a row is updated or deleted. When both supplemental logging and this parameter are set, it ensures that SharePlex can always build a key and that the SharePlex key will match the Oracle key.

See the SharePlex Reference Guide for more information about this parameter.

Configure replication

On the source, create a SharePlex configuration file that specifies capture and routing information. The structure that is required in a configuration file varies, depending on your replication strategy, but this shows you the required syntax for routing data to Kafka.

where:

• SID is the Oracle SID of the source Oracle database.
• src_owner.table is the owner and name of the source table.
• !kafka is a required keyword indicating SharePlex is posting to Kafka.
• :tgt_owner.table is optional and specifies the owner and name of a target table. Use this feature if you want the data to appear as if it came from a table other than the source table. Allow no spaces between !kafka and :tgt_owner.table. Type case-sensitive names in the correct case and enclose them within double quotes, as in "MySchema"."MyTable"

• host is the name of the target system.

Note: See Configure data replication.

Source configuration example

Configure SharePlex on the target

These instructions configure the SharePlex Post process to connect to Kafka. You must have a running Kafka broker.

To configure post to Kafka

1. Create a Kafka topic.
2. Start sp_cop. (Do not activate the configuration yet.)
3. Run sp_ctrl.

4. Issue the target command to configure posting to a Kafka broker and topic. The following are example commands.

   sp_ctrl> target x.kafkaset kafka broker=host1:9092,host2:9092,host3:9092

   sp_ctrl> target x.kafka set kafka topic=shareplex

   See View and change Kafka settings for command explanations and options.

   Note: Specify more than one broker so that SharePlex will attempt to connect to the other brokers in the list if any one of them is down.

Set the Kafka record format

SharePlex can output to either XML or JSON format as input to Kafka. XML is the default. To set the input format and specify format options, use one of the following target commands:

target x.kafka set format record=json

or:

target x.kafka set format record=xml

To view samples of these formats, see the format category of the target command documentation in the SharePlex Reference Guide.

View and change Kafka settings

To view current property settings for output to Kafka, use the following target command:

target x.kafka show

To change a property setting, use the following command.

target x.kafka [queue queuename] set kafka property=value

where:

• queue queuename is the name of a Post queue. Use this option if there are multiple Post processes.
• property and value are shown in the following table.

Table 3: Kafka target properties

* To avoid latency, if Post detects no more incoming messages, it sends the packet to Kafka immediately without waiting for the threshold to be satisfied.

Set recovery options

If the Kafka process aborts suddenly, or if the machine that it is running on aborts, row changes may be written twice to the Kafka topic. The consumer must manage this by detecting and discarding duplicates.

Every record of every row-change operation in a transaction has the same transaction ID and is also marked with a sequence ID. These attributes are id and msgIdx, respectively, under the txn element in the XML output (see Set up replication from Oracle to Kafka).

The transaction ID is the SCN at the time the transaction was committed, and the sequence ID is the index of the row change in the transaction. These two values are guaranteed to be the same if they are re-written to the Kafka topic in a recovery situation.

If desired, you can configure Post to include additional metadata with every row-change record by using the following command:

target x.kafka [queue queuename] set metadata property[, property]

Table 4: Optional metadata properties

Example

target x.kafka set metadata time, userid, trans, size

To reset the metadata

target x.kafka [queue queuename] reset metadata

To view the metadata

target x.kafka [queue queuename] show metadata

Set up replication from Oracle to a SQL or XML file

Overview

SharePlex can post replicated Oracle data to a file formatted as SQL or XML. This data is written as a sequential series of operations as they occurred on the source, which can then be posted in sequential order to a target database or consumed by an external process or program.

These instructions contain setup instructions that are specific to this target. Install SharePlex on the source and target according to the appropriate directions in this manual before performing these setup steps.

For the versions, data types and operations that are supported when using SharePlex to replicate to this target, see the SharePlex Release Notes.

Configure SharePlex on the source

On the source, create a SharePlex configuration file that specifies capture and routing information. The structure that is required in a configuration file varies, depending on your replication strategy, but this shows you the required syntax for routing data to a SQL or XML file.

where:

• SID is the Oracle SID of the source Oracle database.

• src_owner.table is the owner and name of the source table.

• !file is a required keyword that directs Post to write to a file.
• tgt_owner.table is optional and specifies the owner and name of the target table. Use if either component is different from that of the source table.
• host is the name of the target system.

Note: For more information, see Configure data replication in the SharePlex Administration Guide.

Source configuration example:

The following example replicates the parts table in schema PROD from Oracle instance ora112 to a file on target system sysprod.

Configure SharePlex on the target

By default, SharePlex formats data to a file in XML format, and there is no target setup required unless you want to change properties of the output file (see Set up replication from Oracle to a SQL or XML file.) To output in SQL format, use the target command to specify the SQL output as follows.

To output data in SQL format

1. Start sp_cop.
2. Start sp_ctrl.

3. Issue the following required target commands to output the records in SQL. Note: Use all lower-case characters.

   target x.file [queue queuename] set format record=sql

   target x.file [queuequeuename] set sql legacy=yes

   where: queue queuename constrains the action of the command to the SharePlex Post process that is associated with the specified queue.

   See Set up replication from Oracle to a SQL or XML file for descriptions of these settings and other optional properties that you can set.

To view samples of the SQL and XML formats, see the target command documentation in the SharePlex Reference Guide.

View and change target settings

To view current property settings for output to a file, use the following command:

target x.file show

To change a setting, use the following target command.

target x.file [queue queuename] set [category] property=value

target.

File storage and aging

Post writes to a series of files. The active working file is prepended with the label of current_ and is stored in the opx/current subdirectory of the variable-data directory.

Important: Do not open or edit the current_ file.

Post uses the max_records, max_size and max_time parameters to determine the point at which to start a new active file. When this switch occurs, Post moves the processed data to a sequenced file in the opx subdirectory of the variable-data directory. The file names include the name of the post queue, the time and date, and an incrementing ID.

SQL files:

/installed/vardir> ls -1 opx

0000000000_20140305130858_legacy.sql

0000000001_20140305131130_legacy.sql

0000000002_20140305131212_legacy.sql

0000000003_20140305133835_legacy.sql

0000000004_20140305134028_legacy.sql

XML files:

/installed/vardir> ls -1 opx

0000000000_20140305130858_prodsys.XML

0000000001_20140305131130_prodsys.XML

0000000002_20140305131212_prodsys.XML

0000000003_20140305133835_prodsys.XML

0000000004_20140305134028_prodsys.XML

To force a file switch

The current file cannot be viewed or consumed without stopping Post. To access the data in the current file, you can use the target command with the switch option to move the data to a sequenced file, from which it can then be consumed or viewed. After issuing this command, the switch occurs after Post processes a new record.

target x.file [queue queuename] switch

Generic SharePlex demonstration-all platforms

Contents

Prework for the demonstrations

Before you run the basic demonstrations, have the following items available.

Tables used in the demonstrations

You will replicate splex.demo_src from the source system to splex.demo_dest on the target system. These tables are installed by default into the SharePlex schema, which in these demonstrations is "splex." Your SharePlex schema may be different. Verify that these tables exist.

Description of the demo tables.

INSERT scripts

• Create a SQL script named insert_demo_src that inserts and commits 500 rows into the splex.demo_src table. You will run this script during some of the demonstrations.
• If you will be using the demonstration of named post queues, create a SQL script named insert_demo_dest that inserts and commits 500 rows into the splex.demo_dest table. You will run this script during some of the demonstrations.