OSLC Query 2.0 does not define any means for a client to query a specified textual property for a partial match, such as "contains", or other string pattern-matching capabilities. I found a number of discussions in Jazz.net forums asking for such a feature. A common requirement is to query for change reqeusts whose summary/title contains a keyword. While oslc.searchTerms provides some means of finding change requests of interest, the result could contain results where text of interest is used in any textaul properties.
RTC appears to allow "*" in a string literal value as a match anything.
GCM supports the use of "%" and "_" in string values and the "=" operator is then implemented using a case-insenstive SQL LIKE.
Since we have a few implementation attempting to address this requirement, I'd like to see such a feature standardized but a MAY rather than a MUST.
The use of "%" and "_" from SQL like is preferable because it is easily implementable on RDB based applications, and can easily be transformed into a SPARQL regular expression for RDF/SPARQL based applications.