MarkLogic 12 EA 1 Product Documentation
xdmp.mergexdmp.merge(
[options as Object?]
) as null
Summary
Starts merging the forests of the database, subject to specified
options.
Parameters |
options |
Options with which to customize this operation.
This function supports
the following options:
- mergeTimestamp
- Fragments with a timestamp of this or newer are not garbage collected
during this merge.
A negative value means the timestamp is relative to the time the merge
starts, at ten million ticks per second.
For example, -6000000000 means ten minutes before the merge.
The default is 0, which means not specifying a timestamp.
- mergeMaxSize
- The maximum allowable size, in megabytes, of a resultant stand.
The default value is taken from the database configuration.
A value of 0 means there is no limit.
It is possible for a stand larger than the merge-max-size to merge if
the stand has enough deleted fragments to trigger the merge min ratio;
in this case, MarkLogic will do a single-stand merge, merging out the
deleted fragments (even if the resulting stand is larger than the
merge-max-size value specified).
- mergePriority
- The CPU scheduler priority for the merge ("normal" or "lower").
- singleStand
- If any forests in the database have a single stand and this parameter
is false, do not merge them. The default is
true .
- forests
- Specifies the IDs of the forests in which to perform merges.
The value of this option is an array of
forest IDs, as string values.
The default is to merge all of the forests in the database.
|
Required Privileges
This operation requires at least one of the following privileges:
http://marklogic.com/xdmp/privileges/xdmp-merge
http://marklogic.com/xdmp/privileges/xdmp-merge/database/{id}
Example
xdmp.merge({ mergeMaxSize: 500,
mergeTimestamp: 8273,
singleStand: false,
forests: [
xdmp.forest("my-forest"),
xdmp.forest("my-other-forest")
]
});
// Performs a merge on my-forest and my-other-forest. If a stand
// created by this merge would be greater than 500 megabytes, the merge
// will be limited and not all stands will be merged (as many as can be
// merged under 500 MB will be merged). If my-forest or my-other-forest
// have only one stand, they will not be merged. Any fragments with
// timestamp 8273 or newer will not be garbage collected.
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