Dealing with delayed Tags.

[rysavy-ondrej]

How to deal with tags that are not provided on time?

Is it possible to update the host context with tags coming late?

[rysavy-ondrej]

One possibility is to use SERIAL ID for tracking the tags in the enhancement_data table.

WINDOW-BASED DETECTION: If the ID is later than the last ID used for completing the window and the validity intersects the window, then we detected the tag, which was missed.

When computing host context objects, we should freeze the enhancement data to those of max ID when closing the window -> it can be done by adding another condition in the where clause "ID < window.max_tag_id".

For maintaining this we need a new table for windows:

CREATE TABLE window
{
    id SERIAL PRIMARY KEY,  
    max_tag_id BIGINT,
    validity TSRANGE
} 

CONTEXT-BASED DETECTION: Or we can add ID of the last tag within the host_context:

...
    max_tag_id BIGINT,

then when a delayed tag is identified it would be possible to directly search the affected contexts.

UPDATE: How to perform the tag update? TODO!

[rysavy-ondrej]

Systematically implemented via ContextProvider:

• we have static tags, ,e.g, Netify which are used when context is builded
• we have dynamic tags, e.g., those from SmartADS, and these are used when the context objects are retrieved.