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Developer's Guide - MapGuide Open Source - OSGeo

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Spatial filters are used to select features based on their geometry. For example,<br />

you could use a spatial filter to select all roads that intersect a certain area.<br />

Basic Filters<br />

Basic filters perform logical tests of feature properties. You can construct<br />

complex queries by combining expressions. Expressions use the comparison<br />

operators below:<br />

Operator<br />

=<br />

<br />

<<br />

<br />

>=<br />

LIKE<br />

Meaning<br />

Equality<br />

Not equal<br />

Less than<br />

Less than or equal to<br />

Greater than<br />

Greater than or equal to<br />

Used for string comparisons. The “%” wildcard represents<br />

any sequence of 0 or more characters. The “_” wildcard<br />

represents any single character. For example, “LIKE<br />

Schmitt%” will search for any names beginning with<br />

“Schmitt”.<br />

The comparison operators can be used with numeric or string properties,<br />

except for the LIKE operator, which can only be used with string properties.<br />

Combine or modify expressions with the standard boolean operators AND, OR,<br />

and NOT.<br />

36 | Chapter 3 Working With Feature Data

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