Data Model
Data model for CPS Temporal is limited to one entity to store configuration and state data with its timestamp.
The store keeps a new data instance each time a new data observation is made for a given dataspace, schema set and anchor.
Timestamp is used to partition time-series data.
Implementation
PostgreSQL database is proposed to implement CPS Temporal data store.
Timescale PostgreSQL extension is proposed for time-series data implementation.
By implementing PostgreSQL and its Timescale extension, CPS Temporal benefits from:
- Time-series data features on top of standard well know Postgres database
- All PostgreSQL relational database features
- CPS previous experience with PostgreSQL (default reference implementation for CPS Core)
- PostgreSQL JSONB data type for configuration and state data
Detailed schema information:
cpstemporaldb=# \d network_data
Table "public.network_data"
Column | Type | Collation | Nullable | Default
------------+--------------------------+-----------+----------+---------
timestamp | timestamp with time zone | | not null |
dataspace | character varying(255) | | not null |
schema_set | character varying(255) | | not null |
anchor | character varying(255) | | not null |
payload | jsonb | | not null |
version | timestamp with time zone | | not null |
Indexes:
"network_data_dataspace_schema_set_anchor_timestamp_idx" UNIQUE, btree (dataspace, schema_set, anchor, "timestamp" DESC)
"network_data_payload_idx" gin (payload)
"network_data_timestamp_idx" btree ("timestamp" DESC)
cpstemporaldb=# SELECT * FROM timescaledb_information.dimensions;
hypertable_schema | hypertable_name | dimension_number | column_name | column_type | dimension_type | time_interval | integer_interval | integer_now_func | num_partitions
-------------------+-----------------+------------------+-------------+--------------------------+----------------+---------------+------------------+------------------+----------------
public | network_data | 1 | timestamp | timestamp with time zone | Time | 1 day | | |
(1 row)