Supported filter languages

Data filtering in GeoServer is based on the concepts found in the OGC Filter Encoding Specification.

GeoServer accepts filters encoded in two different languages: Filter Encoding and Common Query Language.

Filter Encoding

The Filter Encoding language is an XML-based method for defining filters. XML Filters can be used in the following places in GeoServer:

  • in WMS GetMap requests, using the filter parameter
  • in WFS GetFeature requests, using the filter parameter
  • in SLD Rules, in the Filter element

The Filter Encoding language is defined by OGC Filter Encoding Standards:

  • Filter Encoding 1.0 is used in WFS 1.0 and SLD 1.0
  • Filter Encoding 1.1 is used in WFS 1.1
  • Filter Encoding 2.0 is used in WFS 2.0

CQL/ECQL

CQL (Common Query Language) is a plain-text language created for the OGC Catalog specification. GeoServer has adapted it to be an easy-to-use filtering mechanism. GeoServer actually implements a more powerful extension called ECQL (Extended CQL), which allows expressing the full range of filters that OGC Filter 1.1 can encode. ECQL is accepted in many places in GeoServer:

The ECQL Reference describes the features of the ECQL language. The CQL and ECQL tutorial shows examples of defining filters.

The CQL and ECQL languages are defined in: