PURGEMARKERHISTORY

Valid For

Manager

Description

Use the PURGEMARKERHISTORY parameter to control the size of the Oracle GoldenGate marker table. This parameter purges rows that are not needed any more. You can purge the marker table at any time. This parameter is only valid for an Oracle database in which the capture configuration uses the Oracle GoldenGate DDL trigger to support DDL replication. For more information about the Oracle GoldenGate DDL objects, see Installing and Configuring Oracle GoldenGate for Oracle Database.

To determine the name of the marker table, Oracle GoldenGate first looks for a name specified with the MARKERTABLE parameter in the GLOBALS file. If that parameter does not exist, Oracle GoldenGate uses the default name of GGS_MARKER.

You can specify maximum and minimum lengths of time to keep a row, based on the last modification date. Both maximum and minimum rules must be specified; otherwise Manager does not have complete criteria for when to delete the row. For example, MINKEEPHOURS 3 used with MAXKEEPHOURS 5 specifies to keep rows that have not been modified in the past three hours, but delete them when they have not been modified for at least five hours.

PURGEMARKERHISTORY requires a logon to be specified with the USERID or USERIDALIAS parameter and, depending on the type of database, the SOURCEDB parameter.

Default

Purge every hour

Syntax

PURGEMARKERHISTORY
{, max_rule}
[, min_rule]
[, frequency]
max_rule

Required. Can be one of the following to set the maximum amount of time to keep rows.

MAXKEEPHOURS n

Purges if the row has not been modified for n number of hours.

MAXKEEPDAYS n

Purges if the row has not been modified for n number of days.

min_rule

Can be one of the following to set the minimum amount of time to keep rows.

MINKEEPHOURS n

Keeps an unmodified row for at least the specified number of hours.

MINKEEPDAYS n

Keeps an unmodified row for at least the specified number of days.

frequency

Sets the frequency with which to purge marker history. The default interval at which Manager evaluates potential maintenance tasks is 10 minutes, as specified with the CHECKMINUTES parameter. At that interval, Manager evaluates the PURGEMARKERHISTORY frequency and conducts the purge at the specified frequency.

frequency can be one of the following:

FREQUENCYMINUTES n

Sets the frequency, in minutes, with which to purge marker history. The default purge frequency is 60 minutes.

FREQUENCYHOURS n

Sets the frequency, in hours, at which to purge marker history.

See "CHECKMINUTES" for more information about controlling the interval between Manager maintenance checks.

Example

The following example keeps all rows that have not been modified in the past three days and deletes them when they have not been modified for at least five days. The purge frequency is 30 minutes.

PURGEMARKERHISTORY MINKEEPDAYS 3, MAXKEEPDAYS 5, FREQUENCYMINUTES 30