# Message Selectors

A message selector is a string that lets a client program specify a set of messages, based on the values of message headers and properties. A selector matches a message if, after substituting header and property values from the message into the selector string, the string evaluates to true. Consumers can request that the server deliver only those messages that match a selector.

The syntax of selectors is based on a subset of the SQL92 conditional expression syntax.

Copyright © Cloud Software Group, Inc. All rights reserved.