# Create a data quality monitor
Follow these steps to continuously monitor the data quality of time series:
# Step 1. Create a monitor and rule sets
To create a monitor:
In the left-hand menu, select Quality monitoring.
Select + Create.
Enter a name for your monitor and a description to indicate what the monitor will be used for, or what kind of data the monitor includes.
Select the users that can edit the monitor.
Select Create to create the monitor.
Group time series with similar data quality requirements into rule sets, and add as many rule sets as you need.
To create a rule set and start adding data to your monitor, select + Add new rule set.
Search and filter to find the time series you want to add to your rule set.
Select the time series that you want to add to your rule set.
Select Add to monitor.
Select edit time series to add or remove time series, or go to monitor to view the data in your monitor.
Note: Each monitor can contain a maximum of 500 time series and each rule set a maximum of 150 time series.
# Step 2. Add data quality monitoring to rule sets
Add data quality monitoring to a rule set to specify the data quality requirements for a group of time series.
In Fusion, open an existing monitor and then a rule set.
Go to the rules tab and select Add rules to specify the quality requirements for the time series in the rule set.
Define the time window that matches the requirements of your data science model or application.
The time window specifies how far back the data quality monitor should check that the selected time series meet the data quality requirements.
Note: The time window has to be between 1 minute and 3 hours. We recommend that you specify a time window between 1 minute and 30 minutes.
Select the data quality rules.
Different models and apps have different data quality requirements and will need to be monitored for different aspects of data quality. Select which data quality rules to apply to the time series in each rule set:
- Max age of the last data point - checks that the latency is acceptable for each of the time series in the rule set.
- Max distance between data points - monitors the gap between any two data points in each of the time series in the rule set.
- Min number of data points - checks that the number of data points in the defined time window is high enough for each of the time series in the rule set.
- Max value - checks that the data points are below a max value for each of the time series in the rule set.
- Min value - checks that the data points are above a minimum value for each of the time series in the rule set.
Set up notifications.
Specify the email addresses and/or a webhook URL to notify if the data quality fails to meet the requirements, and when data quality returns to normal.
A webhook lets an app provide other applications with real-time information. You can use a tool like Opsgenie to receive the notification and pass it on to the relevant recipients through email, Slack, or other mediums.