Technical data

Defining Queries
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The Purposes of Queries
When should you perform a query?
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When you want to work on data contained in more than one
drawing at the same time.
You can create a Map project and query the objects from two or
more drawings. This type of object query actually copies the source
objects into the Map project. You can then edit the objects from
different drawings simultaneously, and save the edits back to the
source drawing if you want.
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When you have two or more drawings that were created in
different coordinate zones.
You can create a Map project and assign to it the coordinate zone
in which you want to work. You can then query the other
drawings, and the drawings’ information is converted to the zone
of the Map project when it is brought in.
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When you have two or more drawings that were created using
different units.
You can create a Map project and then perform an object
conversion when you query the other drawings. The object
conversion can scale the source drawings so that their units match
when you bring them into the Map project.
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When you want to create a thematic map.
A thematic map shows map features by either continuous or
discrete categories. For example, you can perform a thematic query
to show wetlands and buildable areas, using different colors to
indicate the different regions.
Key Concepts
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You can create legends for thematic maps. Legends describe the
symbols and colors that are used in a thematic map.
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There are several ways to query objects. You can query objects by
location, layer name, block name, elevation, color, line type, and
so on.
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You can alter object properties, such as line width and scale,
during queries.