In the BlueGIS software, various queries can be performed on the layer data in the operation menu under the layer attribute table. To access the queries, click on the Queries button in the Operations menu after opening the layer attribute table menü.

Step 1: Attribute Table Operations

There are two types of queries.

• Attribute Queries

• Spatial Queries

1. Attribute Queries

Click on Attribute Queries option in the Queries menu.

In the Attribute query panel, select the column that you want to query and select the query type.

After making the selection, the value box opens according to the option selected below. Write the value in the box that drop-down and click the 'Add Query' button.

Add as many queries as desired. But do not forget that queries work together. To run the queries added to the list click the Query button.

The result of the query is shown in the attribute table.

2. Spatial Queries

Click on the 'Spatial Queries' option in the Queries menu.

Select the query. Various queries are available. Query list:

• Length

• Area

• Find intersection geometries

• Find the geometries that are in it

• Find what's in the geometry

• Find overlapping geometries

• Find non-intersecting geometries

There may be different input parameters depending on the query selected. Here, the area query is selected as an example.

The query is run with the Apply button and the results are displayed in the attribute table.