5.3.1.1 LogChannelMetadata

The WITSML SIG formed a working group to study the business requirements for organizing Log data. Stemming from the work of that group, WITSML 2 now has the concept of a metadata record that describes logging information in a way that will make it easier to find logs in a consistent repeatable way, across multiple vendors and service companies. This metadata appears on all Channel objects. The full description of all of the elements in the metadata record can be found in the WITSML Technical Reference Guide.

The metadata record also appears on higher aggregations of Channels (such as ChannelSet and Log). In these cases, to aggregate various metadata tags, follow these rules:

1. In general, if all the Channels in the aggregate have the same value for a given metadata tag, then that value is promoted to the aggregate object. For example, if a ChannelSet is created where all Channels have the same LoggingCompanyName and Code, then those values appear in the metadata for the ChannelSet.
2. For StartIndex and EndIndex, the aggregate object values are a single range consisting of the minimum and maximum values from all of the input Channels.
3. All other fields can be replaced with either a ‘*’ character (indicating it contains multiple values) or a comma-separated list of the distinct values found among all of the Channels in the set.