2004

758 | Chapter 26 Access External Databases
5 Enter a value in Through, or choose Look Up Values (Through).
The query searches for all values less than or equal to the value that you
specify.
6 If you want to save the query in the current drawing for future use, choose
Store.
7 Choose Execute to execute the query and close the dialog box.
Use the Query Builder
The Query Builder tab is the primary AutoCAD query environment. Unlike
the Quick Query and Range Query tabs, the Query Builder can be used to
create queries based on multiple criteria. You can also parenthetically group
criteria and specify what fields are displayed and how they are sorted when
the query is returned in the Data View window.
The Query Builder tab introduces Boolean operators and parenthetical group-
ing, which are used to create compound queries based on two or more search
criteria. For example, using Boolean operators, you can generate a query that
returns a list of all light fixtures of a given type that were installed after a
specific date.
■ And Operator. Constructs a query based on multiple criteria, returning a
set of records that meet all specified criteria. For example, search for all
rooms that are offices and are currently unoccupied. The query returns
records for all rooms that are both offices and unoccupied.
■ Or Operator. Constructs a query based on multiple criteria, returning a set
of records that meet any of the specified criteria. For example, search for
all rooms that are offices or are currently unoccupied. The query returns
records for all rooms that are either offices or unoccupied.
■ Parenthetical Grouping. Groups a series of search criteria by bracketing
them within parentheses. For example, search for
(All rooms that are offices and are currently unoccupied)
or
(All rooms that are cubicles and are currently unoccupied)
This query returns a list of all unoccupied offices and cubicles.
You can nest up to four sets of parentheses within a statement.