Guide: How to filter datasets
Filter using the user interface
The filter option is a fantastic method of optimising dataset performance. Particularly for 'big' datasets this helps to reduce the size of the data.
The benefits of filtering are:
- Quick way to view the data rows you are interested in
- Saves time downloading data because of reduced download size
- Easier to manage complex visualisations
In this example we will use the soil sensor readings dataset to filter to a certain sensor location.
1. View the Data
To get started, open the soil sensor readings datasets by clicking here.
Once you are on the dataset primer page you can view the data by clicking 'View Data' button.
This opens the dataset in a table view, which is shown in the image below:
2. Use the filter option
Once you are viewing the data table you have the option to filter the data. To begin filtering, click the 'Filter' button .
This opens up the filter pane.
3. Using the filter pane
After clicking the filter button, the filter pane will show on the left side of the screen. The filter pane allows you to define a filter condition.
In this example we will be filtering the data using the site_id column.
If we only wanted readings for the Conservatory site we would determine a criteria to match.
This particular criteria is where the site_id column equals '75508' (the Conservatory location's site id). So we'll need to construct a filter condition.
To do this click 'Add a New Filter Condition' (shown on the image left).
This allows us to filter this dataset based on its contents.
3. Setting the filter condition
The first step is to set the column to filter the data by. This is done by clicking on the selected column name. In this example the column 'id' was selected by default, but we want to set it to site_id.
To change the selected column, click on the column name shown in blue text, underlined with a downward arrow next to it.
This will bring a popup box (shown the left) to select the column that you want to filter by.
For our criteria we are setting this as site_id.
Select an operation
Once the column has been selected you will now set an operation to filter by.
The operation allows us to set the range of values to select from. Commonly these are selections where the value 'is' or 'is not' a certain value (but can be other more advanced options).
For this example we will use the 'is' operation.
4. Set a value filter value
Now we have set the filter column and operation we will set the desired value to filter on.
The filter operation uses a value to know which rows to match and return.
In this example we are filtering for the site_id column to be 75508 (which is the Conservatory site).
Set this value by entering it into the textbox.
One the value is set, press enter on your keyboard to apply the filter.
Data is now filtered
Once the dataset has a filter, the table view of the data will now only show the associated records that match your filter condition.
In this example (to the left) all the rows are returned match our criteria where: site_id is 75508.
Useful tip: This number of filtered records is shown at the bottom right of the table. It will display text: 'Showing Soil moisture probe readings 1 to 100 out of 56,488'