Querying historical data in SCADA systems - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of querying historical data in SCADA systems?

Querying historical data helps to analyze past system performance, detect trends, and troubleshoot issues by reviewing recorded sensor and event data.

beginner

Name a common method to query historical data in SCADA systems.

Using SQL-like queries on the SCADA historian database to retrieve time-stamped data records.

beginner

What does a time range filter do in a historical data query?

It limits the data retrieved to a specific start and end time, focusing the analysis on a particular period.

intermediate

Why is data aggregation useful when querying historical data?

Aggregation summarizes large data sets into averages, sums, or counts, making it easier to understand trends over time.

beginner

What is a historian in the context of SCADA systems?

A historian is a specialized database that stores time-stamped data from sensors and devices for long-term analysis.

What type of data does a SCADA historian store?

A Time-stamped sensor and event data

B User login credentials

C Real-time video streams

D Network configuration files

A SCADA historian stores time-stamped sensor and event data for analysis.

Which query filter helps to select data from a specific period?

A Priority filter

B Time range filter

C Device type filter

D User filter

A time range filter limits data to a chosen start and end time.

Why use aggregation functions in historical data queries?

A To summarize data for easier trend analysis

B To delete old data

C To encrypt data

D To speed up real-time data collection

Aggregation summarizes data, making trends easier to see.

Which of these is NOT typically stored in a SCADA historian?

A Alarm history

B Event logs

C Sensor readings

D User passwords

User passwords are not stored in the historian; it stores operational data.

What is the main benefit of querying historical data?

A To backup current system settings

B To control devices in real-time

C To analyze past system behavior and improve decisions

D To monitor network traffic

Querying historical data helps analyze past behavior for better decisions.

Explain how you would use a time range filter when querying historical data in a SCADA system.

Think about selecting data only from certain dates or hours.

Describe the role of a historian database in managing SCADA system data.

Consider it as a special storage for past system information.