SQL is a powerful tool for analysing the time series data.

One of the most common functions used in SQL for time series data analysis is the GROUP BY clause.

The group by clause allows you to group data based on a specific time interval, such as hour, day, week, or month.

The DATE_TRUNC sql function allows you to truncate a date or timestamp to a specific time interval, such as hour, day, week, or month

SQL also provides several built-in functions for working with dates and times

In addition to basic filtering and aggregation functions, SQL also provides powerful window functions, such as LAG, LEAD.

SQL also provides several statistical functions, such as AVG, SUM, and COUNT

SQL also allows you to join multiple time series datasets together, which can be useful for performing cross-sectional analysis.