X-Git-Url: http://git.indexdata.com/?p=idzebra-moved-to-github.git;a=blobdiff_plain;f=doc%2Fquerymodel.xml;h=f5d69338b0addb553360fc6949b9b50d7c17565c;hp=ff0107b15ac4df5c6f1cebaa2a4b36874aaa6126;hb=c3ff843e467932c6027a8b3b2ebda7b44612447e;hpb=d2a2cd0f1bb0a5f31bfc59039012efae30d8955e diff --git a/doc/querymodel.xml b/doc/querymodel.xml index ff0107b..f5d6933 100644 --- a/doc/querymodel.xml +++ b/doc/querymodel.xml @@ -1,304 +1,291 @@ - Query Model - - - Query Model Overview - - + +
+ Query Model Overview + +
Query Languages - + - Zebra is born as a networking Information Retrieval engine adhering - to the international standards - Z39.50 and - SRU, - and implement the - type-1 Reverse Polish Notation (RPN) query + &zebra; is born as a networking Information Retrieval engine adhering + to the international standards + &acro.z3950; and + &acro.sru;, + and implement the + type-1 Reverse Polish Notation (&acro.rpn;) query model defined there. Unfortunately, this model has only defined a binary encoded representation, which is used as transport packaging in - the Z39.50 protocol layer. This representation is not human - readable, nor defines any convenient way to specify queries. + the &acro.z3950; protocol layer. This representation is not human + readable, nor defines any convenient way to specify queries. - Since the type-1 (RPN) + Since the type-1 (&acro.rpn;) query structure has no direct, useful string representation, every client application needs to provide some form of mapping from a local query notation or representation to it. - - - - Prefix Query Format (PQF) + + +
+ Prefix Query Format (&acro.pqf;) - Index Data has defined a textual representation in the + Index Data has defined a textual representation in the Prefix Query Format, short - PQF, which maps - one-to-one to binary encoded - type-1 RPN queries. - PQF has been adopted by other - parties developing Z39.50 software, and is often referred to as - Prefix Query Notation, or in short - PQN. See - for further explanations and - descriptions of Zebra's capabilities. - - - - - Common Query Language (CQL) - - The query model of the type-1 RPN, - expressed in PQF/PQN is natively supported. - On the other hand, the default SRU + &acro.pqf;, which maps + one-to-one to binary encoded + type-1 &acro.rpn; queries. + &acro.pqf; has been adopted by other + parties developing &acro.z3950; software, and is often referred to as + Prefix Query Notation, or in short + &acro.pqn;. See + for further explanations and + descriptions of &zebra;'s capabilities. + +
+ +
+ Common Query Language (&acro.cql;) + + The query model of the type-1 &acro.rpn;, + expressed in &acro.pqf;/&acro.pqn; is natively supported. + On the other hand, the default &acro.sru; web services Common Query Language - CQL is not natively supported. + &acro.cql; is not natively supported. - Zebra can be configured to understand and map CQL to PQF. See + &zebra; can be configured to understand and map &acro.cql; to &acro.pqf;. See . - - - +
+ +
- +
Operation types - Zebra supports all of the three different - Z39.50/SRU operations defined in the - standards: explain, search, - and scan. A short description of the - functionality and purpose of each is quite in order here. + &zebra; supports all of the three different + &acro.z3950;/&acro.sru; operations defined in the + standards: explain, search, + and scan. A short description of the + functionality and purpose of each is quite in order here. - +
Explain Operation - The syntax of Z39.50/SRU queries is + The syntax of &acro.z3950;/&acro.sru; queries is well known to any client, but the specific semantics - taking into account a particular servers functionalities and abilities - must be - discovered from case to case. Enters the - explain operation, which provides the means - for learning which + discovered from case to case. Enters the + explain operation, which provides the means for learning which fields (also called indexes or access points) are provided, which default parameter the server uses, which retrieve document formats are defined, and which specific parts - of the general query model are supported. + of the general query model are supported. - The Z39.50 embeds the explain operation - by performing a - search in the magic + The &acro.z3950; embeds the explain operation + by performing a + search in the magic IR-Explain-1 database; - see . + see . - In SRU, explain is an entirely separate - operation, which returns an ZeeRex - XML record according to the + In &acro.sru;, explain is an entirely separate + operation, which returns an ZeeRex &acro.xml; record according to the structure defined by the protocol. In both cases, the information gathered through - explain operations can be used to + explain operations can be used to auto-configure a client user interface to the servers - capabilities. + capabilities. - +
- + - +
Scan Operation - The scan operation is a helper functionality, - which operates on one index or access point a time. + The scan operation is a helper functionality, + which operates on one index or access point a time. It provides the means to investigate the content of specific indexes. Scanning an index returns a handful of terms actually found in - the indexes, and in addition the scan + the indexes, and in addition the scan operation returns the number of documents indexed by each term. A search client can use this information to propose proper - spelling of search terms, to auto-fill search boxes, or to + spelling of search terms, to auto-fill search boxes, or to display controlled vocabularies. - +
- +
- +
- - - Prefix Query Format syntax and semantics +
+ &acro.rpn; queries and semantics - The PQF grammar - is documented in the YAZ manual, and shall not be - repeated here. This textual PQF representation - is not transmistted to Zebra during search, but it is in the - client mapped to the equivalent Z39.50 binary - query parse tree. + The &acro.pqf; grammar + is documented in the &yaz; manual, and shall not be + repeated here. This textual &acro.pqf; representation + is not transmitted to &zebra; during search, but it is in the + client mapped to the equivalent &acro.z3950; binary + query parse tree. - - - PQF tree structure + +
+ &acro.rpn; tree structure - The PQF parse tree - or the equivalent textual representation - - may start with one specification of the + The &acro.rpn; parse tree - or the equivalent textual representation in &acro.pqf; - + may start with one specification of the attribute set used. Following is a query - tree, which - consists of atomic query parts (APT) or + tree, which + consists of atomic query parts (&acro.apt;) or named result sets, eventually - paired by boolean binary operators, and - finally recursively combined into - complex query trees. + paired by boolean binary operators, and + finally recursively combined into + complex query trees. - - + +
Attribute sets Attribute sets define the exact meaning and semantics of queries - issued. Zebra comes with some predefined attribute set + issued. &zebra; comes with some predefined attribute set definitions, others can easily be defined and added to the configuration. - - - - - +
Attribute sets predefined in Zebra
+ Attribute sets predefined in &zebra; + - - - - - - - - + + Attribute set + &acro.pqf; notation (Short hand) + Status + Notes + + + - - - - - - - - - - - - - - - - - - - + and semantics. + predefined + + + &acro.bib1; + bib-1 + Standard &acro.pqf; query language attribute set which defines the + semantics of &acro.z3950; searching. In addition, all of the + non-use attributes (types 2-14) define the hard-wired + &zebra; internal query + processing. + default + + + GILS + gils + Extension to the &acro.bib1; attribute set. + predefined + +
Attribute setShort handStatusNotes
Explainexp-1Special attribute set used on the special automagic + + Explain + exp-1 + Special attribute set used on the special automagic IR-Explain-1 database to gain information on server capabilities, database names, and database - and semantics.predefined
Bib1bib-1Standard PQF query language attribute set which defines the - semantics of Z39.50 searching. In addition, all of the - non-use attributes (type 2-9) define the hard-wired - Zebra internal query - processing.default
GILSgilsExtension to the Bib1 attribute set.predefined
- - - The use attributes (type 1) mappings the - predefined attribute sets are found in the - attribute set configuration files tab/*.att. - + + The use attributes (type 1) mappings the + predefined attribute sets are found in the + attribute set configuration files tab/*.att. + - - The Zebra internal query processing is modeled after - the Bib1 attribute set, and the non-use - attributes type 2-6 are hard-wired in. It is therefore essential - to be familiar with . - + + + The &zebra; internal query processing is modeled after + the &acro.bib1; attribute set, and the non-use + attributes type 2-6 are hard-wired in. It is therefore essential + to be familiar with . + + + +
- - +
Boolean operators A pair of sub query trees, or of atomic queries, is combined using the standard boolean operators into new query trees. Thus, boolean operators are always internal nodes in the query tree. - - - +
Boolean operators
+ Boolean operators + - - - - - - + + Keyword + Operator + Description + + - - - - - - - - - - - - - - - - + @and + binary AND operator + Set intersection of two atomic queries hit sets + + @or + binary OR operator + Set union of two atomic queries hit sets + + @not + binary AND NOT operator + Set complement of two atomic queries hit sets + + @prox + binary PROXIMITY operator + Set intersection of two atomic queries hit sets. In + addition, the intersection set is purged for all + documents which do not satisfy the requested query + term proximity. Usually a proper subset of the AND + operation. + +
KeywordOperatorDescription
@andbinary AND operatorSet intersection of two atomic queries hit sets
@orbinary OR operatorSet union of two atomic queries hit sets
@notbinary AND NOT operatorSet complement of two atomic queries hit sets
@proxbinary PROXIMITY operatorSet intersection of two atomic queries hit sets. In - addition, the intersection set is purged for all - documents which do not satisfy the requested query - term proximity. Usually a proper subset of the AND - operation.
- + - For example, we can combine the terms - information and retrieval + For example, we can combine the terms + information and retrieval into different searches in the default index of the default attribute set as follows. Querying for the union of all documents containing the terms information OR - retrieval: + retrieval: Z> find @or information retrieval @@ -306,7 +293,7 @@ Querying for the intersection of all documents containing the terms information AND - retrieval: + retrieval: The hit set is a subset of the corresponding OR query. @@ -318,8 +305,8 @@ terms information AND retrieval, taking proximity into account: The hit set is a subset of the corresponding - AND query - (see the PQF grammar for + AND query + (see the &acro.pqf; grammar for details on the proximity operator): Z> find @prox 0 3 0 2 k 2 information retrieval @@ -329,60 +316,60 @@ Querying for the intersection of all documents containing the terms information AND retrieval, in the same order and near each - other as described in the term list. + other as described in the term list. The hit set is a subset of the corresponding PROXIMITY query. Z> find "information retrieval" - - - - - Atomic queries (APT) +
+ + +
+ Atomic queries (&acro.apt;) Atomic queries are the query parts which work on one access point - only. These consist of an attribute list - followed by a single term or a - quoted term list, and are often called - Attributes-Plus-Terms (APT) queries. + only. These consist of an attribute list + followed by a single term or a + quoted term list, and are often called + Attributes-Plus-Terms (&acro.apt;) queries. - Atomic (APT) queries are always leaf nodes in the PQF query tree. - UN-supplied non-use attributes type 2-9 are either inherited from - higher nodes in the query tree, or are set to Zebra's default values. - See for details. + Atomic (&acro.apt;) queries are always leaf nodes in the &acro.pqf; query tree. + UN-supplied non-use attributes types 2-12 are either inherited from + higher nodes in the query tree, or are set to &zebra;'s default values. + See for details. - - - +
Atomic queries (APT)
+ Atomic queries (&acro.apt;) + - - - - - - + + Name + Type + Notes + + - - - - - - - - - - + inherited, are set to the default &zebra; configuration values. + + + + term + single term + or quoted term list + Here the search terms or list of search terms is added + to the query + +
NameTypeNotes
attribute listList of orthogonal attributesAny of the orthogonal attribute types may be omitted, + + attribute list + List of orthogonal attributes + Any of the orthogonal attribute types may be omitted, these are inherited from higher query tree nodes, or if not - inherited, are set to the default Zebra configuration values. -
termsingle term - or quoted term list Here the search terms or list of search terms is added - to the query
Querying for the term information in the @@ -408,33 +395,33 @@ - The scan operation is only supported with - atomic APT queries, as it is bound to one access point at a + The scan operation is only supported with + atomic &acro.apt; queries, as it is bound to one access point at a time. Boolean query trees are not allowed during - scan. - - + scan. + + For example, we might want to scan the title index, starting with - the term + the term debussy, and displaying this and the following terms in lexicographic order: Z> scan @attr 1=4 debussy - - - - +
+ + +
Named Result Sets - Named result sets are supported in Zebra, and result sets can be + Named result sets are supported in &zebra;, and result sets can be used as operands without limitations. It follows that named - result sets are leaf nodes in the PQF query tree, exactly as - atomic APT queries are. + result sets are leaf nodes in the &acro.pqf; query tree, exactly as + atomic &acro.apt; queries are. - + After the execution of a search, the result set is available at the server, such that the client can use it for subsequent searches or retrieval requests. The Z30.50 standard actually @@ -443,12 +430,12 @@ send a diagnostic to the effect that the requested result set does not exist any more. - + Defining a named result set and re-using it in the next query, - using yaz-client. Notice that the client, not - the server, assigns the string '1' to the - named result set. + using yaz-client. Notice that the client, not + the server, assigns the string '1' to the + named result set. Z> f @attr 1=4 mozart ... @@ -459,32 +446,33 @@ Number of hits: 14, setno 2 - + - Named result sets are only supported by the Z39.50 protocol. - The SRU web service is stateless, and therefore the notion of - named result sets does not exist when accessing a Zebra server by - the SRU protocol. + + Named result sets are only supported by the &acro.z3950; protocol. + The &acro.sru; web service is stateless, and therefore the notion of + named result sets does not exist when accessing a &zebra; server by + the &acro.sru; protocol. + - +
- - - Zebra's special access point of type 'string' +
+ &zebra;'s special access point of type 'string' - The numeric use (type 1) attribute is usually + The numeric use (type 1) attribute is usually referred to from a given - attribute set. In addition, Zebra let you use + attribute set. In addition, &zebra; let you use any internal index - name defined in your configuration + name defined in your configuration as use attribute value. This is a great feature for debugging, and when you do not need the complexity of defined use attribute values. It is - the preferred way of accessing Zebra indexes directly. + the preferred way of accessing &zebra; indexes directly. Finding all documents which have the term list "information - retrieval" in an Zebra index, using it's internal full string + retrieval" in an &zebra; index, using its internal full string name. Scanning the same index. Z> find @attr 1=sometext "information retrieval" @@ -493,7 +481,7 @@ Searching or scanning - the bib-1 use attribute 54 using it's string name: + the bib-1 use attribute 54 using its string name: Z> find @attr 1=Code-language eng Z> scan @attr 1=Code-language "" @@ -502,7 +490,7 @@ It is possible to search in any silly string index - if it's defined in your - indexation rules and can be parsed by the PQF parser. + indexing rules and can be parsed by the &acro.pqf; parser. This is definitely not the recommended use of this facility, as it might confuse your users with some very unexpected results. @@ -511,55 +499,57 @@ - See also for details, and - - for the SRU PQF query extension using string names as a fast + See also for details, and + + for the &acro.sru; &acro.pqf; query extension using string names as a fast debugging facility. - - - - Zebra's special access point of type 'XPath' - for GRS filters +
+ +
+ &zebra;'s special access point of type 'XPath' + for &acro.grs1; filters As we have seen above, it is possible (albeit seldom a great - idea) to emulate + idea) to emulate XPath 1.0 based - search by defining use (type 1) - string attributes which in appearance + search by defining use (type 1) + string attributes which in appearance resemble XPath queries. There are two problems with this approach: first, the XPath-look-alike has to - be defined at indexation time, no new undefined + be defined at indexing time, no new undefined XPath queries can entered at search time, and second, it might confuse users very much that an XPath-alike index name in fact - gets populated from a possible entirely different XML element - than it pretends to access. + gets populated from a possible entirely different &acro.xml; element + than it pretends to access. - When using the GRS Record Model - (see ), we have the - possibility to embed life + When using the &acro.grs1; Record Model + (see ), we have the + possibility to embed life XPath expressions - in the PQF queries, which are here called - use (type 1) xpath - attributes. You must enable the - xpath enable directive in your - .abs configuration files. + in the &acro.pqf; queries, which are here called + use (type 1) xpath + attributes. You must enable the + xpath enable directive in your + .abs configuration files. - Only a very restricted subset of the - XPath 1.0 - standard is supported as the GRS record model is simpler than - a full XML DOM structure. See the following examples for - possibilities. + + Only a very restricted subset of the + XPath 1.0 + standard is supported as the &acro.grs1; record model is simpler than + a full &acro.xml; &acro.dom; structure. See the following examples for + possibilities. + - Finding all documents which have the term "content" - inside a text node found in a specific XML DOM - subtree, whose starting element is - addressed by XPath. + Finding all documents which have the term "content" + inside a text node found in a specific &acro.xml; &acro.dom; + subtree, whose starting element is + addressed by XPath. - Z> find @attr 1=/root content + Z> find @attr 1=/root content Z> find @attr 1=/root/first content Notice that the @@ -570,22 +560,22 @@ It follows that the above searches are interpreted as: - Z> find @attr 1=/root//text() content + Z> find @attr 1=/root//text() content Z> find @attr 1=/root/first//text() content - + Searching inside attribute strings is possible: - Z> find @attr 1=/link/@creator morten + Z> find @attr 1=/link/@creator morten - + - + Filter the addressing XPath by a predicate working on exact string values in - attributes (in the XML sense) can be done: return all those docs which + attributes (in the &acro.xml; sense) can be done: return all those docs which have the term "english" contained in one of all text sub nodes of the subtree defined by the XPath /record/title[@lang='en']. And similar @@ -593,70 +583,71 @@ Z> find @attr 1=/record/title[@lang='en'] english Z> find @attr 1=/link[@creator='sisse'] sibelius - Z> find @attr 1=/link[@creator='sisse']/description[@xml:lang='da'] sibelius + Z> find @attr 1=/link[@creator='sisse']/description[@xml:lang='da'] sibelius - - - Combining numeric indexes, boolean expressions, + + + Combining numeric indexes, boolean expressions, and xpath based searches is possible: Z> find @attr 1=/record/title @and foo bar Z> find @and @attr 1=/record/title foo @attr 1=4 bar - + - Escaping PQF keywords and other non-parseable XPath constructs - with '{ }' to prevent syntax errors: + Escaping &acro.pqf; keywords and other non-parseable XPath constructs + with '{ }' to prevent client-side &acro.pqf; parsing + syntax errors: Z> find @attr {1=/root/first[@attr='danish']} content Z> find @attr {1=/record/@set} oai - It is worth mentioning that these dynamic performed XPath - queries are a performance bottleneck, as no optimized - specialized indexes can be used. Therefore, avoid the use of - this facility when speed is essential, and the database content - size is medium to large. + + It is worth mentioning that these dynamic performed XPath + queries are a performance bottleneck, as no optimized + specialized indexes can be used. Therefore, avoid the use of + this facility when speed is essential, and the database content + size is medium to large. + +
+
- - - - - +
Explain Attribute Set - The Z39.50 standard defines the + The &acro.z3950; standard defines the Explain attribute set - Exp-1, which is used to discover information + Exp-1, which is used to discover information about a server's search semantics and functional capabilities - Zebra exposes a "classic" + &zebra; exposes a "classic" Explain database by base name IR-Explain-1, which - is populated with system internal information. + is populated with system internal information. - - The attribute-set exp-1 consists of a single - use attribute (type 1). + + The attribute-set exp-1 consists of a single + use attribute (type 1). In addition, the non-Use - bib-1 attributes, that is, the types - Relation, Position, - Structure, Truncation, - and Completeness are imported from - the bib-1 attribute set, and may be used - within any explain query. + &acro.bib1; attributes, that is, the types + Relation, Position, + Structure, Truncation, + and Completeness are imported from + the &acro.bib1; attribute set, and may be used + within any explain query. - - - Use Attributes (type = 1) + +
+ Use Attributes (type = 1) The following Explain search attributes are supported: - ExplainCategory (@attr 1=1), - DatabaseName (@attr 1=3), - DateAdded (@attr 1=9), + ExplainCategory (@attr 1=1), + DatabaseName (@attr 1=3), + DateAdded (@attr 1=9), DateChanged(@attr 1=10). @@ -666,26 +657,26 @@ DatabaseInfo, AttributeDetails. - See tab/explain.att and the - Z39.50 standard + See tab/explain.att and the + &acro.z3950; standard for more information. - - - +
+ +
Explain searches with yaz-client Classic Explain only defines retrieval of Explain information - via ASN.1. Practically no Z39.50 clients supports this. Fortunately - they don't have to - Zebra allows retrieval of this information + via ASN.1. Practically no &acro.z3950; clients supports this. Fortunately + they don't have to - &zebra; allows retrieval of this information in other formats: - SUTRS, XML, - GRS-1 and ASN.1 Explain. + &acro.sutrs;, &acro.xml;, + &acro.grs1; and ASN.1 Explain. - + List supported categories to find out which explain commands are - supported: + supported: Z> base IR-Explain-1 Z> find @attr exp1 1=1 categorylist @@ -693,7 +684,7 @@ Z> show 1+2 - + Get target info, that is, investigate which databases exist at this server endpoint: @@ -708,7 +699,7 @@ Z> show 1+1 - + List all supported databases, the number of hits is the number of databases found, which most commonly are the @@ -722,7 +713,7 @@ Z> show 1+2 - + Get database info record for database Default. @@ -735,13 +726,13 @@ Z> find @attrset exp1 @and @attr 1=1 databaseinfo @attr 1=3 Default - + Get attribute details record for database Default. - This query is very useful to study the internal Zebra indexes. + This query is very useful to study the internal &zebra; indexes. If records have been indexed using the alvis - XSLT filter, the string representation names of the known indexes can be + &acro.xslt; filter, the string representation names of the known indexes can be found. Z> base IR-Explain-1 @@ -753,180 +744,206 @@ Z> find @attrset exp1 @and @attr 1=1 attributedetails @attr 1=3 Default - - - - - - Bib1 Attribute Set +
+ +
+ +
+ &acro.bib1; Attribute Set Most of the information contained in this section is an excerpt of - the ATTRIBUTE SET BIB-1 (Z39.50-1995) - SEMANTICS, - found at . The BIB-1 - Attribute Set Semantics from 1995, also in an updated - Bib-1 - Attribute Set + the ATTRIBUTE SET &acro.bib1; (&acro.z3950;-1995) SEMANTICS + found at . The &acro.bib1; + Attribute Set Semantics from 1995, also in an updated + &acro.bib1; + Attribute Set version from 2003. Index Data is not the copyright holder of this information, except for the configuration details, the listing of - Zebra's capabilities, and the example queries. + &zebra;'s capabilities, and the example queries. - - - + + +
Use Attributes (type 1) - - A use attribute specifies an access point for any atomic query. - These access points are highly dependent on the attribute set used - in the query, and are user configurable using the following - default configuration files: - tab/bib1.att, - tab/dan1.att, - tab/explain.att, and - tab/gils.att. - New attribute sets can be added by adding new - tab/*.att configuration files, which need to - be sourced in the main configuration zebra.cfg. + + A use attribute specifies an access point for any atomic query. + These access points are highly dependent on the attribute set used + in the query, and are user configurable using the following + default configuration files: + tab/bib1.att, + tab/dan1.att, + tab/explain.att, and + tab/gils.att. + + + For example, some few &acro.bib1; use + attributes from the tab/bib1.att are: + + att 1 Personal-name + att 2 Corporate-name + att 3 Conference-name + att 4 Title + ... + att 1009 Subject-name-personal + att 1010 Body-of-text + att 1011 Date/time-added-to-db + ... + att 1016 Any + att 1017 Server-choice + att 1018 Publisher + ... + att 1035 Anywhere + att 1036 Author-Title-Subject + + + + New attribute sets can be added by adding new + tab/*.att configuration files, which need to + be sourced in the main configuration zebra.cfg. + + + In addition, &zebra; allows the access of + internal index names and dynamic + XPath as use attributes; see + and + . - - In addition, Zebra allows the access of - internal index names and dynamic - XPath as use attributes; see - and - . - + + Phrase search for information retrieval in + the title-register, scanning the same register afterwards: + + Z> find @attr 1=4 "information retrieval" + Z> scan @attr 1=4 information + + +
- - Phrase search for information retrieval in - the title-register, scanning the same register afterwards: - - Z> find @attr 1=4 "information retrieval" - Z> scan @attr 1=4 information - - - +
- +
+ &zebra; general Bib1 Non-Use Attributes (type 2-6) - - Zebra general Bib1 Non-Use Attributes (type 2-6) - - +
Relation Attributes (type 2) - + Relation attributes describe the relationship of the access - point (left side + point (left side of the relation) to the search term as qualified by the attributes (right side of the relation), e.g., Date-publication <= 1975. - - - + - - - - - - - +
Relation Attributes (type 2)
RelationValueNotes
+ Relation Attributes (type 2) + + + + Relation + Value + Notes + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + Less than + 1 + supported + + + Less than or equal + 2 + supported + + + Equal + 3 + default + + + Greater or equal + 4 + supported + + + Greater than + 5 + supported + + + Not equal + 6 + unsupported + + + Phonetic + 100 + unsupported + + + Stem + 101 + unsupported + + + Relevance + 102 + supported + + + AlwaysMatches + 103 + supported * + +
Less than1supported
Less than or equal2supported
Equal3default
Greater or equal4supported
Greater than5supported
Not equal6unsupported
Phonetic100unsupported
Stem101unsupported
Relevance102supported
AlwaysMatches103supported
+ + + AlwaysMatches searches are only supported if alwaysmatches indexing + has been enabled. See + + - The relation attributes - 1-5 are supported and work exactly as + The relation attributes 1-5 are supported and work exactly as expected. - All ordering operations are based on a lexicographical ordering, - expect when the - structure attribute numeric (109) is used. In - this case, ordering is numerical. See + All ordering operations are based on a lexicographical ordering, + except when the + structure attribute numeric (109) is used. In + this case, ordering is numerical. See . - Z> find @attr 1=Title @attr 2=1 music + Z> find @attr 1=Title @attr 2=1 music ... Number of hits: 11745, setno 1 ... - Z> find @attr 1=Title @attr 2=2 music + Z> find @attr 1=Title @attr 2=2 music ... Number of hits: 11771, setno 2 ... - Z> find @attr 1=Title @attr 2=3 music + Z> find @attr 1=Title @attr 2=3 music ... Number of hits: 532, setno 3 ... - Z> find @attr 1=Title @attr 2=4 music + Z> find @attr 1=Title @attr 2=4 music ... Number of hits: 11463, setno 4 ... - Z> find @attr 1=Title @attr 2=5 music + Z> find @attr 1=Title @attr 2=5 music ... Number of hits: 11419, setno 5 - The relation attribute - Relevance (102) is supported, see + The relation attribute + Relevance (102) is supported, see for full information. - + Ranked search for information retrieval in the title-register: @@ -936,22 +953,22 @@ - The relation attribute - AlwaysMatches (103) is in the default + The relation attribute + AlwaysMatches (103) is in the default configuration - supported in conjecture with structure attribute - Phrase (1) (which may be omitted by - default). + supported in conjecture with structure attribute + Phrase (1) (which may be omitted by + default). It can be configured to work with other structure attributes, - see the configuration file - tab/default.idx and - . + see the configuration file + tab/default.idx and + . - AlwaysMatches (103) is a + AlwaysMatches (103) is a great way to discover how many documents have been indexed in a given field. The search term is ignored, but needed for correct - PQF syntax. An empty search term may be supplied. + &acro.pqf; syntax. An empty search term may be supplied. Z> find @attr 1=Title @attr 2=103 "" Z> find @attr 1=Title @attr 2=103 @attr 4=1 "" @@ -959,236 +976,239 @@ - +
- +
Position Attributes (type 3) - + The position attribute specifies the location of the search term within the field or subfield in which it appears. - - - - - - - - - +
Position Attributes (type 3)
PositionValueNotes
+ Position Attributes (type 3) + + + + Position + Value + Notes + - - - - - - - - - - - - - - - + + First in field + 1 + supported * + + + First in subfield + 2 + supported * + + + Any position in field + 3 + default + +
First in field 1unsupported
First in subfield2unsupported
Any position in field3default
- - - The position attribute values first in field (1), - and first in subfield(2) are unsupported. - Using them does not trigger an error, but silently defaults to - any position in field (3). - + + + + &zebra; only supports first-in-field seaches if the + firstinfield is enabled for the index + Refer to . + &zebra; does not distinguish between first in field and + first in subfield. They result in the same hit count. + Searching for first position in (sub)field in only supported in &zebra; + 2.0.2 and later. - - - + +
+ +
Structure Attributes (type 4) - + The structure attribute specifies the type of search term. This causes the search to be mapped on - different Zebra internal indexes, which must have been defined - at index time. + different &zebra; internal indexes, which must have been defined + at index time. - - The possible values of the + + The possible values of the structure attribute (type 4) can be defined - using the configuration file - tab/default.idx. + using the configuration file tab/default.idx. The default configuration is summarized in this table. - - - - - - - - - +
Structure Attributes (type 4)
StructureValueNotes
+ Structure Attributes (type 4) + + + + Structure + Value + Notes + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + Phrase + 1 + default + + + Word + 2 + supported + + + Key + 3 + supported + + + Year + 4 + supported + + + Date (normalized) + 5 + supported + + + Word list + 6 + supported + + + Date (un-normalized) + 100 + unsupported + + + Name (normalized) + 101 + unsupported + + + Name (un-normalized) + 102 + unsupported + + + Structure + 103 + unsupported + + + Urx + 104 + supported + + + Free-form-text + 105 + supported + + + Document-text + 106 + supported + + + Local-number + 107 + supported + + + String + 108 + unsupported + + + Numeric string + 109 + supported + +
Phrase 1default
Word2supported
Key3supported
Year4supported
Date (normalized)5supported
Word list6supported
Date (un-normalized)100unsupported
Name (normalized) 101unsupported
Name (un-normalized) 102unsupported
Structure103unsupported
Urx104supported
Free-form-text105supported
Document-text106supported
Local-number107supported
String108unsupported
Numeric string109supported
- + + The structure attribute values + Word list (6) + is supported, and maps to the boolean AND + combination of words supplied. The word list is useful when + Google-like bag-of-word queries need to be translated from a GUI + query language to &acro.pqf;. For example, the following queries + are equivalent: + + Z> find @attr 1=Title @attr 4=6 "mozart amadeus" + Z> find @attr 1=Title @and mozart amadeus + + - - The structure attribute values - Word list (6) - is supported, and maps to the boolean AND - combination of words supplied. The word list is useful when - google-like bag-of-word queries need to be translated from a GUI - query language to PQF. For example, the following queries - are equivalent: - - Z> find @attr 1=Title @attr 4=6 "mozart amadeus" - Z> find @attr 1=Title @and mozart amadeus - - + + The structure attribute value + Free-form-text (105) and + Document-text (106) + are supported, and map both to the boolean OR + combination of words supplied. The following queries + are equivalent: + + Z> find @attr 1=Body-of-text @attr 4=105 "bach salieri teleman" + Z> find @attr 1=Body-of-text @attr 4=106 "bach salieri teleman" + Z> find @attr 1=Body-of-text @or bach @or salieri teleman + + This OR list of terms is very useful in + combination with relevance ranking: + + Z> find @attr 1=Body-of-text @attr 2=102 @attr 4=105 "bach salieri teleman" + + - - The structure attribute value - Free-form-text (105) and - Document-text (106) - are supported, and map both to the boolean OR - combination of words supplied. The following queries - are equivalent: - - Z> find @attr 1=Body-of-text @attr 4=105 "bach salieri teleman" - Z> find @attr 1=Body-of-text @attr 4=106 "bach salieri teleman" - Z> find @attr 1=Body-of-text @or bach @or salieri teleman - - This OR list of terms is very useful in - combination with relevance ranking: - - Z> find @attr 1=Body-of-text @attr 2=102 @attr 4=105 "bach salieri teleman" - - - - - The structure attribute value - Local number (107) - is supported, and maps always to the Zebra internal document ID, - irrespectively which use attribute is specified. The following queries - have exactly the same unique record in the hit set: - - Z> find @attr 4=107 10 - Z> find @attr 1=4 @attr 4=107 10 - Z> find @attr 1=1010 @attr 4=107 10 - - + + The structure attribute value + Local number (107) + is supported, and maps always to the &zebra; internal document ID, + irrespectively which use attribute is specified. The following queries + have exactly the same unique record in the hit set: + + Z> find @attr 4=107 10 + Z> find @attr 1=4 @attr 4=107 10 + Z> find @attr 1=1010 @attr 4=107 10 + + - - In - the GILS schema (gils.abs), the - west-bounding-coordinate is indexed as type n, - and is therefore searched by specifying - structure=Numeric String. - To match all those records with west-bounding-coordinate greater - than -114 we use the following query: - - Z> find @attr 4=109 @attr 2=5 @attr gils 1=2038 -114 - - + + In + the GILS schema (gils.abs), the + west-bounding-coordinate is indexed as type n, + and is therefore searched by specifying + structure=Numeric String. + To match all those records with west-bounding-coordinate greater + than -114 we use the following query: + + Z> find @attr 4=109 @attr 2=5 @attr gils 1=2038 -114 + + - The exact mapping between PQF queries and Zebra internal indexes - and index types is explained in + + The exact mapping between &acro.pqf; queries and &zebra; internal indexes + and index types is explained in . - + + +
- - +
Truncation Attributes (type = 5) @@ -1198,54 +1218,54 @@ document hit set of a search query. - - - - - - - - - +
Truncation Attributes (type 5)
TruncationValueNotes
+ Truncation Attributes (type 5) + + + + Truncation + Value + Notes + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + Right truncation + 1 + supported + + + Left truncation + 2 + supported + + + Left and right truncation + 3 + supported + + + Do not truncate + 100 + default + + + Process # in search term + 101 + supported + + + RegExpr-1 + 102 + supported + + + RegExpr-2 + 103 + supported + +
Right truncation 1supported
Left truncation2supported
Left and right truncation3supported
Do not truncate100default
Process # in search term101supported
RegExpr-1 102supported
RegExpr-2103supported
@@ -1269,10 +1289,10 @@ ... Number of hits: 95, setno 8 - + - The truncation attribute value + The truncation attribute value Process # in search term (101) is a poor-man's regular expression search. It maps each # to .*, and @@ -1285,10 +1305,10 @@ Number of hits: 89, setno 10 - + - The truncation attribute value - Regexp-1 (102) is a normal regular search, + The truncation attribute value + Regexp-1 (102) is a normal regular search, see for details. Z> find @attr 1=Body-of-text @attr 5=102 schnit+ke @@ -1297,13 +1317,13 @@ - The truncation attribute value - Regexp-2 (103) is a Zebra specific extension + The truncation attribute value + Regexp-2 (103) is a &zebra; specific extension which allows fuzzy matches. One single error in spelling of search terms is allowed, i.e., a document is hit if it includes a term which can be mapped to the used search term by one character substitution, addition, deletion or - change of position. + change of position. Z> find @attr 1=Body-of-text @attr 5=100 schnittke ... @@ -1314,106 +1334,109 @@ Number of hits: 103, setno 15 ... - - - - - Completeness Attributes (type = 6) + +
+ +
+ Completeness Attributes (type = 6) The Completeness Attributes (type = 6) - is used to specify that a given search term or term list is either - part of the terms of a given index/field + is used to specify that a given search term or term list is either + part of the terms of a given index/field (Incomplete subfield (1)), or is what literally is found in the entire field's index (Complete field (3)). - + - - - - - - - - +
Completeness Attributes (type = 6)
CompletenessValueNotes
+ Completeness Attributes (type = 6) + + + + Completeness + Value + Notes + - - - - - - - - - - - - - - - + + Incomplete subfield + 1 + default + + + Complete subfield + 2 + deprecated + + + Complete field + 3 + supported + +
Incomplete subfield1default
Complete subfield2depreciated
Complete field3supported
The Completeness Attributes (type = 6) is only partially and conditionally supported in the sense that it is ignored if the hit index is - not of structure type="w" or + not of structure type="w" or type="p". - + Incomplete subfield (1) is the default, and - makes Zebra use - register type="w", whereas + makes &zebra; use + register type="w", whereas Complete field (3) triggers search and scan in index type="p". - The Complete subfield (2) is a reminiscens - from the happy MARC - binary format days. Zebra does not support it, but maps silently + The Complete subfield (2) is a reminiscent + from the happy &acro.marc; + binary format days. &zebra; does not support it, but maps silently to Complete field (3). - The exact mapping between PQF queries and Zebra internal indexes - and index types is explained in + + The exact mapping between &acro.pqf; queries and &zebra; internal indexes + and index types is explained in . - - - - - + + +
+ +
+
- - Advanced Zebra PQF Features +
+ Extended &zebra; &acro.rpn; Features - The Zebra internal query engine has been extended to specific needs + The &zebra; internal query engine has been extended to specific needs not covered by the bib-1 attribute set query model. These extensions are non-standard and non-portable: most functional extensions are modeled over the bib-1 attribute set, - defining type 7-9 attributes. - There are also the special + defining type 7 and higher values. + There are also the special string type index names for the - idxpath attribute set. + idxpath attribute set. - - - Zebra specific retrieval of all records + +
+ &zebra; specific retrieval of all records - Zebra defines a hardwired string index name + &zebra; defines a hardwired string index name called _ALLRECORDS. It matches any record - contained in the database, if used in conjunction with - the relation attribute + contained in the database, if used in conjunction with + the relation attribute AlwaysMatches (103). - + The _ALLRECORDS index name is used for total database export. The search term is ignored, it may be empty. @@ -1432,402 +1455,466 @@ - The special string index _ALLRECORDS is - experimental, and the provided functionality and syntax may very - well change in future releases of Zebra. + + The special string index _ALLRECORDS is + experimental, and the provided functionality and syntax may very + well change in future releases of &zebra;. + - - +
- - Zebra specific Search Extensions to all Attribute Sets + +
+ +
+ &zebra; Regular Expressions in Truncation Attribute (type = 5) - - Zebra Regular Expressions in Truncation Attribute (type = 5) - Each term in a query is interpreted as a regular expression if the truncation value is either Regxp-1 (@attr 5=102) @@ -2245,84 +2331,75 @@ Both query types follow the same syntax with the operands: - - - - - - - - - - - - - - - - - - -
Regular Expression Operands
xMatches the character x.
.Matches any character.
[ .. ]Matches the set of characters specified; - such as [abc] or [a-c].
+ + Regular Expression Operands + + + + x + Matches the character x. + + + . + Matches any character. + + + [ .. ] + Matches the set of characters specified; + such as [abc] or [a-c]. + + + +
The above operands can be combined with the following operators: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Regular Expression Operators
x*Matches x zero or more times. - Priority: high.
x+Matches x one or more times. - Priority: high.
x? Matches x zero or once. - Priority: high.
xy Matches x, then y. - Priority: medium.
x|y Matches either x or y. - Priority: low.
( )The order of evaluation may be changed by using parentheses.
+ + Regular Expression Operators + + + + x* + Matches x zero or more times. + Priority: high. + + + x+ + Matches x one or more times. + Priority: high. + + + x? + Matches x zero or once. + Priority: high. + + + xy + Matches x, then y. + Priority: medium. + + + x|y + Matches either x or y. + Priority: low. + + + ( ) + The order of evaluation may be changed by using parentheses. + + + +
If the first character of the Regxp-2 query is a plus character (+) it marks the beginning of a section with non-standard specifiers. The next plus character marks the end of the section. - Currently Zebra only supports one specifier, the error tolerance, - which consists one digit. + Currently &zebra; only supports one specifier, the error tolerance, + which consists one digit. @@ -2348,95 +2425,90 @@ Z> find @attr 1=4 @attr 5=102 @attr 2=102 "informat.* retrieval" - +
+ - - + - - Server Side CQL to PQF Query Translation +
+ Server Side &acro.cql; to &acro.pqf; Query Translation Using the <cql2rpn>l2rpn.txt</cql2rpn> - YAZ Frontend Virtual + &yaz; Frontend Virtual Hosts option, one can configure - the YAZ Frontend CQL-to-PQF - converter, specifying the interpretation of various - CQL + the &yaz; Frontend &acro.cql;-to-&acro.pqf; + converter, specifying the interpretation of various + &acro.cql; indexes, relations, etc. in terms of Type-1 query attributes. - + - For example, using server-side CQL-to-PQF conversion, one might + For example, using server-side &acro.cql;-to-&acro.pqf; conversion, one might query a zebra server like this: - querytype cql Z> find text=(plant and soil) ]]> - and - if properly configured - even static relevance ranking can - be performed using CQL query syntax: + and - if properly configured - even static relevance ranking can + be performed using &acro.cql; query syntax: - find text = /relevant (plant and soil) ]]> - + - By the way, the same configuration can be used to - search using client-side CQL-to-PQF conversion: - (the only difference is querytype cql2rpn - instead of + By the way, the same configuration can be used to + search using client-side &acro.cql;-to-&acro.pqf; conversion: + (the only difference is querytype cql2rpn + instead of querytype cql, and the call specifying a local conversion file) - querytype cql2rpn Z> find text=(plant and soil) ]]> - + Exhaustive information can be found in the - Section "Specification of CQL to RPN mappings" in the YAZ manual. - - http://www.indexdata.dk/yaz/doc/tools.tkl#tools.cql.map, - and shall therefore not be repeated here. - - - - - +
- +