Storing and identifying metadata through extended properties in a historization system

1. A historian system comprising:

a processor configured and arranged to be coupled to a network connection;

a non-transitory memory device coupled to the processor, comprising processor executable instructions for, when executed, receiving and responding to messages; and

a tag metadata database module comprising processor executable instructions stored on a non-transitory computer readable medium that when executed implements:

storing, in a tag metadata database, tag metadata of data received via the network connection, wherein the tag metadata has a predefined set of properties; and

retrieving the tag metadata in response to one or more requests received via the network connection or from within the historian system;

creating user-defined extended properties for the tag metadata in response to requests received via the network connection, wherein the extended properties each include a tenant ID, and wherein the tenant ID is used to filter the extended properties to retrieve one or more of the extended properties associated with a tenant that requested extended property data;

storing the extended properties in an extended properties database;

retrieving the extended properties from the extended properties database in response to requests received via the network connection or from within the historian system;

indexing extended properties, the indexes enabling the extended properties to be found in the extended properties database;

searching the indexed extended properties in response to requests; and

providing indexes of extended properties stored by the extended property database module.

2. The historian system of claim 1 , wherein the system is connected to a plurality of client devices via the network connection.

3. The historian system of claim 2 , wherein a first client device of the plurality of client devices is associated with a first tenant and a second client device of the plurality of client devices is associated with a second tenant.

4. The historian system of claim 1 , wherein storing the extended properties further comprises:

storing the extended properties as extended property documents in a first collection of extended property documents;

monitoring a remaining capacity of the first collection of extended property documents; and

migrating a plurality of extended property documents from the first collection to a second collection of extended property documents upon detecting that storing the extended property documents in the first collection would cause the first collection to exceed its remaining capacity.

5. The historian system of claim 4 , wherein the first collection of extended property documents comprises extended property documents from more than one tenant.

6. The historian system of claim 1 , further comprising instructions for, when executed, assigning a property of one of searchable and not searchable to the extended properties; and

further comprising instructions for, when executed, indexing extended properties only if the extended properties have been assigned a searchable property.

7. A method for creating extended metadata properties in a historian system comprising:

receiving a first request to create a user-defined extended property for a tag metadata instance, wherein the tag metadata instance has a pre-defined set of properties, and wherein the extended property includes a tenant ID;

locating a record of the tag metadata instance;

updating the record of the tag metadata instance to include the extended property;

creating a document of the extended property in an extended property database of the historian system; and

indexing the extended property document in the search index of the historian system, wherein the tenant ID is used to filter extended properties to retrieve a requested record associated with a tenant.

8. The method of claim 7 , wherein the first request to create an extended property is received by the historian system from a first client device coupled to the historian system by a network.

9. The method of claim 8 , wherein a second request to create an extended property is received by the historian system from a second client device, and wherein the first and second client devices are associated with separate tenants.

10. The method of claim 7 , wherein the first request to create an extended property is received through a representational state transfer (REST) interface.

11. The method of claim 8 , wherein the first request to create an extended property is received through a simple object access protocol (SOAP).

12. The method of claim 7 , wherein the tag metadata instance record is stored separately from the extended property document.

13. The method of claim 7 further comprising:

storing the created extended property document in a first collection of extended property documents;

monitoring a remaining capacity of the first collection of extended property documents; and

migrating a plurality of extended property documents from the first collection to a second collection of extended property documents upon detecting that storing the created extended property document in the first collection would cause the first collection to exceed its remaining capacity.