AutoCAD 2008 User's
Guide > Share Data Between
Drawings and Applications > Access External
Databases >
Use Queries to Filter Database Information
A query to the database is a search criterion that you construct to return the records you want.
The simplest query uses one operator to search one field for a certain value. The range query searches one field to return records that fall within a range you specify.
Boolean operators and parenthetical grouping are used to create queries with two or more search criteria.
If your database is fully compliant with the SQL 92 standard, you can use SQL statements to query more than one database table at a time.
An advanced type of query uses operators on successive selection sets to return a new set of objects or records, which then can be further refined by the same process.
When you save a query, you can later edit it, rename it, and copy it into other drawings.
