Oracle Capture Parameters

The following parameters are valid for the Oracle Capture Process:

Process Parameters

• process – The only appropriate value is capture
• id – Capture Process id
• dbtype – Type of RDBMS, the only possible value is oracle
• name – Name of the Capture Process

Capturing Method and Database Connectivity

• connectiontype – Specifies the Oracle connection method, the possible values are:
  • tns – Local Naming Method to be used
  • ezconnect – EZCONNECT to be used
• tnsname – Name of the TNS alias, valid only if connectiontype=tns
• server – Host name or IP address of the database server, valid only if connectiontype=ezconnect
• port – Database port number, valid only if connectiontype=ezconnect
• servicename – Database service name or SID, valid only if connectiontype=ezconnect
• dbname – Name of either container or pluggable database. Valid only if database=source and for any Oracle versions 12c-19c but excluding RDS instances
• user – Database User name
• password – Database User password
• directlogmode – Used to define Data Capturing Method (see chapter Overview of Data Capturing Methods for the details). The possible values are:
  • 0 – use LogMiner method to capture the data (default)
  • 1 – use Direct Log Mining method to capture the data. If the “locallogdir” parameter is in use the Capture Process will process the Redo Logs from the local directory, otherwise the Capture Process will read the Logs from the Source Database as Oracle directory objects
  • 2 – use Direct Log Mining for Redo Logs located on the ASM device
• asmuser – ASM user name
• asmpassword – ASM user password
• asmservicename – ASM service name or SID
• minearchonly – Determines if the Capture Process must process Archived Redo Logs only. The possible values are:
  • 0 – process Online and Archived Redo Logs (default)
  • 1 – process Archived Redo Logs only
• locallogdir – Path to the local directory to process archived logs from (see chapter Overview of Data Capturing Methods for the details)
• asyncredo – Determines if the Capture Process copies the Redo Logs in a background thread and extracts the changes from the local copy of the logs. The parameter is valid for “directlogmode=1” and “directlogmode=2” only (see Overview of Data Capturing Methods for the details). The possible values are:
  • 0 – extract the changes directly from the Redo Logs (default value)
  • 1 – copy the Redo Logs in the background and extract the changes from the copy (faster)

Note – The local copies of the Redo Logs are kept in the ora<capture id> directory of the Repstance working directory. The “locallogdir” parameter is not used if asyncredo=1.

Note – On the AWS and Azure editions asyncredo=1 needs an instance with at least 32 GB of RAM. On a smaller instance the Capture Process runs as with asyncredo=0 and adds the warning “Async redo mode is not available on this instance” to Incident Management of the Web UI; the incident text says how much memory the instance has. The trial and the on-premises edition have no such limit.

• compressredo – Determines if the Source Database compresses the Redo Logs before it sends them to the Capture Process. The parameter is valid for “directlogmode=1” when the logs are read through the database connection (it is not used with “locallogdir” or with the ASM devices). The possible values are:
  • 0 – do not compress the Redo Logs (default value)
  • 1 – compress the Redo Logs; it saves the network bandwidth at the cost of the CPU of the Source Database

Note – With the compression the archived Redo Logs are read slower. Use it only when the network is the bottleneck.

DML/DDL Replication Objects Specification

• ddlinclude – Mask of the DDL objects to be captured
• ddlexclude – Mask of the DDL objects to be skipped by the Capture Process
• dmlinclude – Mask of the DML objects to be captured
• dmlexclude – Mask of the DML objects to be skipped by the Capture Process
• skiploopback – Used to define the behaviour of a Capture Process when extracting data, which was produced by Apply Processes as part of the “loop-back” control function, in that, this Capture Process will extract or ignore the data. The Apply Processes to be skipped are specified by ids separated by comma. In order to specify all Processes the “all” value to be used. In order to avoid skipping any Apply Processes the “none” value to be used. The default value is “all”.
• map – The set of the parameters to determine objects’ transformation

See Capture Objects Specification for the DML and DML objects specification details and Objects Mapping and Possible Transforms for the objects' transformation details.

Initial Load Objects Specification

• loadinclude – Mask of the objects to be included into the Initial Load
• loadexclude – Mask of the objects to be skipped during Initial Load
• loadconsistent – Determines how the Initial Load reads the tables. The possible values are:
  • 0 – read the tables in slices of about 5 seconds; the redo mining catches up between the slices, each table is consistent as of its own SCN (default value)
  • 1 – read all the tables in one pass as of the same SCN, so the tables are consistent with each other; the Capture Process does not mine the redo during the load, and the Source Database needs enough UNDO (the “ORA-01555” error is possible for big tables)

See chapter Initial Load for more details.

Performance Tuning Parameters

• maxtrailbytes – Size, in bytes, after which the Capture Process closes the current trail file and starts the next one. A trail file can be larger than this size by the size of the last written batch. The default value is 52428800 (50 MiB).

Note – A very small value results in a large number of small trail files.

Other Parameters

• pollingdelay – The parameter is used to specify number of seconds the Capture Process will wait after each database changes gathering
• preview – This parameter is used to validate list of the tables to be included into the replication along with the transformation rules. The possible values are:
  • 0 – do not use “preview” mode (default)
  • 1 – do not apply the configuration to the Capture Process but provide the list of the tables to be included into the replication along with the transformation rules.
• autostart – Determines if the Process must be run automatically, the possible values are:
  • 0 – do not run the Process automatically (default value)
  • 1 – to run the Process automatically
• restartattempts – Number of attempts to restart the failed Capture Process automatically. The server checks the processes every 5 minutes. The value 0 disables the automatic restart. When the attempts are used up, the notification channels (see the “notification” parameter) are informed. The default value is 5.

Note – The number of attempts is restored to the full value as soon as the process makes progress after a failure.

• notification – The ids of the notification channels, separated by comma (see Monitoring Replication for the details on the channels), which are informed by e-mail when the process has failed and can not be restarted automatically any more (see the “restartattempts” parameter). By default nobody is notified.
• debuglevel – The level of debugging, possible values are 0-15, the default value is 0