Function.yaz-search
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yaz_search — Prepares for a search
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Beschreibung
bool yaz_search ( resource $id , string $type , string $query )
yaz_search() prepares for a search on the given
connection.
Like yaz_connect() this function is non-blocking and
only prepares for a search to be executed later when
yaz_wait() is called.
Parameter-Liste
- id
- The connection resource returned by yaz_connect().
- type
- This parameter represents the query type - only "rpn" is supported now in which case the third argument specifies a Type-1 query in prefix query notation.
query
The RPN query is a textual representation 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 operator
precedes the operands. The query string is a sequence of tokens where
white space is ignored unless surrounded by double quotes. Tokens beginning
with an at-character (@) are considered operators,
otherwise they are treated as search terms.
RPN Operators
Construct
Description
@and query1 query2
intersection of query1 and query2
@or query1 query2
union of query1 and query2
@not query1 query2
query1 and not query2
@set name
result set reference
@attrset set query
specifies attribute-set for query. This construction is only allowed
once - in the beginning of the whole query
@attr [set] type=value query
applies 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.
You can find information about attributes at the
[Z39.50 Maintenance Agency]
site.
Hinweis:
If you would like to use a more friendly notation,
use the CCL parser - functions yaz_ccl_conf() and
yaz_ccl_parse().
Rückgabewerte
Gibt bei Erfolg TRUE zurück, im Fehlerfall FALSE.
Beispiele
Beispiel #1 Query Examples You can search for simple terms, like this: computer which matches documents where "computer" occur. No attributes are specified. The query "knuth donald" matches documents where "knuth donald" occur (provided that the server supports phrase search). This query applies two attributes for the same phrase. @attr 1=1003 @attr 4=1 "knuth donald" First attribute is type 1 (Bib-1 use), attribute value is 1003 (Author). Second attribute has is type 4 (structure), value 1 (phrase), so this should match documents where Donald Knuth is author. The query @and @or a b @not @or c d e would in infix notation look like (a or b) and ((c or d) not e). Another, more complex, one: @attrset gils @and @attr 1=4 art @attr 1=2000 company The query as a whole uses the GILS attributeset. The query matches documents where art occur in the title (GILS,BIB-1) and in which company occur as Distributor (GILS).