(PHP4 >= 4.0.1)

yaz_search -- Prepares for a search


int yaz_search (int id, string type, string query)

yaz_search() prepares for a search on the target with given id. The type represents the query type - only "rpn" is supported now in which case the third argument specifies a Type-1 query (RPN). Like yaz_connect() this function is non-blocking and only prepares for a search to be executed later when yaz_wait() is called.

The RPN query

The RPN query is a textual represenation of the Type-1 query as defined by the Z39.50 standard. However, in the text representation as used by YAZ a prefix notation is used, that is the operater precedes the operands. The query string is a sequence of tokens where white space is ignored is ignored unless surrounded by double quotes. Tokens beginning with an at-character (@) are considered operators, otherwise they are treated as search terms.

Table 1. RPN Operators

@and query1 query2intersection of query1 and query2
@or query1 query2union of query1 and query2
@not query1 query2query1 and not query2
@set nameresult set reference
@attrset set queryspecifies attribute-set for query. This construction is only allowed once - in the beginning of the whole query
@attr set type=value queryapplies attribute to query. The type and value are integers specifying the attribute-type and attribute-value respectively. The set, if given, specifies the attribute-set.

The following illustrates valid query constructions:


Matches documents where "computer" occur. No attributes are specified.

"donald knuth"

Matches documents where "donald knuth" occur.

@attr 1=4 art

Attribute type is 1 (Bib-1 use), attribute value is 4 Title), so this should match documents where "art" occur in the title.

@attrset gils @and @attr 1=4 art @attr 1=1003 "donald knuth"

The query as a whole uses the GILS attributeset. The query matches documents where "art" occur in the title and in which "donald knuth" occur in the author.