Filter Expressions

GeoCrew

Filter expression is the part of a query which specifies querying condition. A query evaluates data and returns only the subset of data that meets the conditions of the query. Use expressions to filter geospatial data or select a subset of data. For example, you can create an expression that specifies all parcels whose area is larger than 1000 square meters. A query containing this expression displays or selects only parcels that meet those criteria.


General feature query conditions:



A feature query may be:



Feature filter expressions support following operations:



Filter expressions also support following functions:


Function

Description

Convert()

Converts given expression to a specified object type.

Len()

Returns the length of a specified string.

IsNull()

Tells whether expression resolves to a non-NULL value.

If()

Returns one of the two values depending on the result of a logical expression.

Trim()

Removes all leading and trailing blank characters from string value.

SubString()

Returns a substring from the specified string value.