X-Git-Url: http://git.indexdata.com/?p=idzebra-moved-to-github.git;a=blobdiff_plain;f=doc%2Fexamples.xml;h=ebbac178df224830168ebc8367c93f26a4136753;hp=f2af44421d6e1a8f9c3908e45df5e493b3153b61;hb=27bdd6aa26843aeac89f635ed495996088d8e8aa;hpb=518c06f68ffac6658aa792da45282a165b32ca95 diff --git a/doc/examples.xml b/doc/examples.xml index f2af444..ebbac17 100644 --- a/doc/examples.xml +++ b/doc/examples.xml @@ -1,41 +1,53 @@ - Example Configurations - + Overview - zebraidx and zebrasrv are both + zebraidx and + zebrasrv are both driven by a master configuration file, which may refer to other subsidiary configuration files. By default, they try to use zebra.cfg in the working directory as the - master file; but this can be changed using the -t + master file; but this can be changed using the -c option to specify an alternative master configuration file. - The master configuration file tells Zebra: + The master configuration file tells &zebra;: - Where to find subsidiary configuration files, including - default.idx + Where to find subsidiary configuration files, including both + those that are named explicitly and a few ``magic'' files such + as default.idx, which specifies the default indexing rules. - What attribute sets to recognise in searches. + What record schemas to support. (Subsidiary files specify how + to index the contents of records in those schemas, and what + format to use when presenting records in those schemas to client + software.) - Policy details such as what record type to expect, what - low-level indexing algorithm to use, how to identify potential - duplicate records, etc. + What attribute sets to recognise in searches. (Subsidiary files + specify how to interpret the attributes in terms + of the indexes that are created on the records.) + + + + + + Policy details such as what type of input format to expect when + adding new records, what low-level indexing algorithm to use, + how to identify potential duplicate records, etc. @@ -48,41 +60,49 @@ - Example 1: XML Indexing And Searching + Example 1: &acro.xml; Indexing And Searching - This example shows how Zebra can be used with absolutely minimal + This example shows how &zebra; can be used with absolutely minimal configuration to index a body of - XML + &acro.xml; documents, and search them using - XPath + XPath expressions to specify access points. - Go to the examples/dinosauricon subdirectory + Go to the examples/zthes subdirectory of the distribution archive. - There you will find a records subdirectory, - which contains some raw XML data to be added to the database: in - this case, as single file, genera.xml, - which contain information about all the known dinosaur genera as of - August 2002. + There you will find a Makefile that will + populate the records subdirectory with a file of + Zthes + records representing a taxonomic hierarchy of dinosaurs. (The + records are generated from the family tree in the file + dino.tree.) + Type make records/dino.xml + to make the &acro.xml; data file. + (Or you could just type make dino to build the &acro.xml; + data file, create the database and populate it with the taxonomic + records all in one shot - but then you wouldn't learn anything, + would you? :-) - Now we need to create the Zebra database, which we do with the - Zebra indexer, zebraidx, which is + Now we need to create a &zebra; database to hold and index the &acro.xml; + records. We do this with the + &zebra; indexer, zebraidx, which is driven by the zebra.cfg configuration file. For our purposes, we don't need any - special behaviour - we can use the defaults - so we start with a - minimal file that just tells zebraidx where to + special behaviour - we can use the defaults - so we can start with a + minimal file that just tells zebraidx where to find the default indexing rules, and how to parse the records: - profilePath: .:../../tab:../../../yaz/tab + profilePath: .:../../tab recordType: grs.sgml - That's all you need for a minimal Zebra configuration. Now you can - roll the XML records into the database and build the indexes: + That's all you need for a minimal &zebra; configuration. Now you can + roll the &acro.xml; records into the database and build the indexes: zebraidx update records @@ -100,102 +120,202 @@ . - Now you can use the Z39.50 client program of your choice to execute - XPath-based boolean queries and fetch the XML records that satisfy + Now you can use the &acro.z3950; client program of your choice to execute + XPath-based boolean queries and fetch the &acro.xml; records that satisfy them: - $ yaz-client tcp:@:9999 + $ yaz-client @:9999 Connecting...Ok. - Z> find @attr 1=/GENUS/MEANING @and lizard earthquakes + Z> find @attr 1=/Zthes/termName Sauroposeidon Number of hits: 1 Z> format xml Z> show 1 - <GENUS name="Sauroposeidon" type="with"> - <MEANING>lizard Poseidon <LOW>(Greek god of, among other things, earthquakes)</LOW></MEANING> - <SPECIES name="proteles"> - <AUTHOR type="vide" name="Franklin" year="2000"></AUTHOR> - <AUTHOR name="Wedel, Cifelli, Sanders"></AUTHOR> - </SPECIES> - <PLACE name="Oklahoma"></PLACE> - <TIME value="Albian"></TIME> - <LENGTH value="30" q="1"></LENGTH> - <REMAINS content="rib, cervical vertebrae"></REMAINS> - <ESSAY> - <P> This new <NOMEN name="Brachiosaurus"></NOMEN>-like <LINK content="dinosaur"></LINK> - was perhaps the tallest. With its head raised, it stood 60 feet (nearly - 20 m) tall. </P> - </ESSAY> + <Zthes> + <termId>22</termId> + <termName>Sauroposeidon</termName> + <termType>PT</termType> + <termNote>The tallest known dinosaur (18m)</termNote> + <relation> + <relationType>BT</relationType> + <termId>21</termId> + <termName>Brachiosauridae</termName> + <termType>PT</termType> + </relation> <idzebra xmlns="http://www.indexdata.dk/zebra/"> - <size>593</size> - <localnumber>891</localnumber> - <filename>records/genera.xml</filename> + <size>300</size> + <localnumber>23</localnumber> + <filename>records/dino.xml</filename> </idzebra> - </GENUS> + </Zthes> - Now wasn't that easy? + Now wasn't that nice and easy? + - Example 2: Supporting Z39.50 Searches + Example 2: Supporting Interoperable Searches - You may have noticed as zebraidx was building - the database that it issued a warning, which we ignored at the - time: - - $ zebraidx update records - 00:45:46-08/10: ../../index/zebraidx(5016) [warn] records/genera.xml:0 Couldn't open GENUS.abs [No such file or directory] - - + The problem with the previous example is that you need to know the + structure of the documents in order to find them. For example, + when we wanted to find the record for the taxon + Sauroposeidon, + we had to formulate a complex XPath + /Zthes/termName + which embodies the knowledge that taxon names are specified in a + <termName> element inside the top-level + <Zthes> element. + + + This is bad not just because it requires a lot of typing, but more + significantly because it ties searching semantics to the physical + structure of the searched records. You can't use the same search + specification to search two databases if their internal + representations are different. Consider a different taxonomy + database in which the records have taxon names specified + inside a <name> element nested within a + <identification> element + inside a top-level <taxon> element: then + you'd need to search for them using + 1=/taxon/identification/name + + + How, then, can we build broadcasting Information Retrieval + applications that look for records in many different databases? + The &acro.z3950; protocol offers a powerful and general solution to this: + abstract ``access points''. In the &acro.z3950; model, an access point + is simply a point at which searches can be directed. Nothing is + said about implementation: in a given database, an access point + might be implemented as an index, a path into physical records, an + algorithm for interrogating relational tables or whatever works. + The only important thing is that the semantics of an access + point is fixed and well defined. + + + For convenience, access points are gathered into attribute + sets. For example, the &acro.bib1; attribute set is supposed to + contain bibliographic access points such as author, title, subject + and ISBN; the GEO attribute set contains access points pertaining + to geospatial information (bounding coordinates, stratum, latitude + resolution, etc.); the CIMI + attribute set contains access points to do with museum collections + (provenance, inscriptions, etc.) + + + In practice, the &acro.bib1; attribute set has tended to be a dumping + ground for all sorts of access points, so that, for example, it + includes some geospatial access points as well as strictly + bibliographic ones. Nevertheless, this model + allows a layer of abstraction over the physical representation of + records in databases. + + In the &acro.bib1; attribute set, a taxon name is probably best + interpreted as a title - that is, a phrase that identifies the item + in question. &acro.bib1; represents title searches by + access point 4. (See + The &acro.bib1; Attribute + Set Semantics) + So we need to configure our dinosaur database so that searches for + &acro.bib1; access point 4 look in the + <termName> element, + inside the top-level + <Zthes> element. + + + This is a two-step process. First, we need to tell &zebra; that we + want to support the &acro.bib1; attribute set. Then we need to tell it + which elements of its record pertain to access point 4. + + + We need to create an Abstract Syntax + file named after the document element of the records we're + working with, plus a .abs suffix - in this case, + Zthes.abs - as follows: + + + + + + + + + +attset zthes.att +attset bib1.att +xpath enable +systag sysno none + +xelm /Zthes/termId termId:w +xelm /Zthes/termName termName:w,title:w +xelm /Zthes/termQualifier termQualifier:w +xelm /Zthes/termType termType:w +xelm /Zthes/termLanguage termLanguage:w +xelm /Zthes/termNote termNote:w +xelm /Zthes/termCreatedDate termCreatedDate:w +xelm /Zthes/termCreatedBy termCreatedBy:w +xelm /Zthes/termModifiedDate termModifiedDate:w +xelm /Zthes/termModifiedBy termModifiedBy:w + + + + + Declare Thesaurus attribute set. See zthes.att. + + + + + Declare &acro.bib1; attribute set. See bib1.att in + &zebra;'s tab directory. + + + + + This xelm directive selects contents of nodes by XPath expression + /Zthes/termId. The contents (CDATA) will be + word searchable by Zthes attribute termId (value 1001). + + + + + Make termName word searchable by both + Zthes attribute termName (1002) and &acro.bib1; attribute title (4). + + + + + + After re-indexing, we can search the database using &acro.bib1; + attribute, title, as follows: + +Z> form xml +Z> f @attr 1=4 Eoraptor +Sent searchRequest. +Received SearchResponse. +Search was a success. +Number of hits: 1, setno 1 +SearchResult-1: Eoraptor(1) +records returned: 0 +Elapsed: 0.106896 +Z> s +Sent presentRequest (1+1). +Records: 1 +[Default]Record type: &acro.xml; +<Zthes> + <termId>2</termId> + <termName>Eoraptor</termName> + <termType>PT</termType> + <termNote>The most basal known dinosaur</termNote> + ... + + -