History Data Delete VI

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Updated2023-02-21
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History Data Delete VI

Owning Palette: Historical Access VIs

Requires: OPC UA Toolkit

Deletes history data within a time range.

Example

OPC UA server refnum in specifies the reference data value of the OPC UA server.

node ID specifies the ID of the node. The format of the node ID is ns=<namespace index>;<identifier type>=<identifier>. A node ID contains the following components:

namespace index is a base 10 number that indicates the namespace of the node ID.

If namespace index is 0, the format of the node ID can be <identifier type>=<identifier>. The namespace index for a node that you created with the OPC UA Toolkit is 2.
identifier type represents the type of the identifier and has the following values:

Value Identifier Type

i Numeric

s String

g GUID

b Opaque
identifier is a string value that represents the name of the identifier.

The format of the node ID can also be ns=<namespace index>;<identifier type>=<identifier>@<index>:<index>. For example, ns=2;s=Folder.Array@1:2. This format only applies to the array data type and allows you to read a single element or a range of elements of an array. You cannot use @ in a node name.

For backwards compatibility, node ID also accepts node paths as input for OPC UA servers. You can regard the node path as the string type identifier of the node ID. For example, a node path can be Device.folder.item.

request specifies the start time and the end time that this VI deletes history data.

	start time specifies the timestamp at which this VI deletes the first history data.
	end time specifies the timestamp at which this VI deletes the last history data.