| Oracle® Text Reference 10g Release 2 (10.2) Part Number B14218-01 |
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| Oracle® Text Reference 10g Release 2 (10.2) Part Number B14218-01 |
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|
View PDF |
This appendix provides examples of how to load text into a text column. It also describes the structure of ctxload import files:
A simple way to populate a text table is to create a table with two columns, id and text, using CREATE TABLE and then use the INSERT statement to load the data. This example makes the id column the primary key, which is optional. The text column is VARCHAR2:
create table docs (id number primary key, text varchar2(80));
To populate the text column, use the INSERT statement as follows:
insert into docs values(1, 'this is the text of the first document'); insert into docs values(12, 'this is the text of the second document');
The following example shows how to use SQL*Loader to load mixed format documents from the operating system to a BLOB column. The example has two steps:
create the table
issue the SQL*Loader command that reads control file and loads data into table
See Also:
For a complete discussion on using SQL*Loader, see Oracle9i Database UtilitiesThis example loads to a table articles_formatted created as follows:
CREATE TABLE articles_formatted ( ARTICLE_ID NUMBER PRIMARY KEY , AUTHOR VARCHAR2(30), FORMAT VARCHAR2(30), PUB_DATE DATE, TITLE VARCHAR2(256), TEXT BLOB );
The article_id column is the primary key. Documents are loaded in the text column, which is of type BLOB.
The following command starts the loader, which reads the control file LOADER1.DAT:
sqlldr userid=demo/demo control=loader1.dat log=loader.log
loader1.datThis SQL*Loader control file defines the columns to be loaded and instructs the loader to load the data line by line from loader2.dat into the articles_formatted table. Each line in loader2.dat holds a comma separated list of fields to be loaded.
-- load file example load data INFILE 'loader2.dat' INTO TABLE articles_formatted APPEND FIELDS TERMINATED BY ',' (article_id SEQUENCE (MAX,1), author CHAR(30), format, pub_date SYSDATE, title, ext_fname FILLER CHAR(80), text LOBFILE(ext_fname) TERMINATED BY EOF)
This control file instructs the loader to load data from loader2.dat to the articles_formatted table in the following way:
The ordinal position of the line describing the document fields in loader2.dat is written to the article_id column.
The first field on the line is written to author column.
The second field on the line is written to the format column.
The current date given by SYSDATE is written to the pub_date column.
The title of the document, which is the third field on the line, is written to the title column.
The name of each document to be loaded is read into the ext_fname temporary variable, and the actual document is loaded in the text BLOB column:
loader2.datThis file contains the data to be loaded into each row of the table, articles_formatted.
Each line contains a comma separated list of the fields to be loaded in articles_formatted. The last field of every line names the file to be loaded in to the text column:
Ben Kanobi, plaintext,Kawasaki news article,../sample_docs/kawasaki.txt, Joe Bloggs, plaintext,Java plug-in,../sample_docs/javaplugin.txt, John Hancock, plaintext,Declaration of Independence,../sample_docs/indep.txt, M. S. Developer, Word7,Newsletter example,../sample_docs/newsletter.doc, M. S. Developer, Word7,Resume example,../sample_docs/resume.doc, X. L. Developer, Excel7,Common example,../sample_docs/common.xls, X. L. Developer, Excel7,Complex example,../sample_docs/solvsamp.xls, Pow R. Point, Powerpoint7,Generic presentation,../sample_docs/generic.ppt, Pow R. Point, Powerpoint7,Meeting presentation,../sample_docs/meeting.ppt, Java Man, PDF,Java Beans paper,../sample_docs/j_bean.pdf, Java Man, PDF,Java on the server paper,../sample_docs/j_svr.pdf, Ora Webmaster, HTML,Oracle home page,../sample_docs/oramnu97.html, Ora Webmaster, HTML,Oracle Company Overview,../sample_docs/oraoverview.html, John Constable, GIF,Laurence J. Ellison : portrait,../sample_docs/larry.gif, Alan Greenspan, GIF,Oracle revenues : Graph,../sample_docs/oragraph97.gif, Giorgio Armani, GIF,Oracle Revenues : Trend,../sample_docs/oratrend.gif,
The import file must use the following format for entries in the thesaurus:
phrase BT broader_term NT narrower_term1 NT narrower_term2 . . . NT narrower_termN BTG broader_term NTG narrower_term1 NTG narrower_term2 . . . NTG narrower_termN BTP broader_term NTP narrower_term1 NTP narrower_term2 . . . NTP narrower_termN BTI broader_term NTI narrower_term1 NTI narrower_term2 . . . NTI narrower_termN SYN synonym1 SYN synonym2 . . . SYN synonymN USE synonym1 or SEE synonym1 or PT synonym1 RT related_term1 RT related_term2 . . . RT related_termN SN text language_key: term
is a word or phrase that is defined as having synonyms, broader terms, narrower terms, or related terms.
In compliance with ISO-2788 standards, a TT marker can be placed before a phrase to indicate that the phrase is the top term in a hierarchy; however, the TT marker is not required. In fact, ctxload ignores TT markers during import.
A top term is identified as any phrase that does not have a broader term (BT, BTG, BTP, or BTI).
Note:
The thesaurus query operators (SYN, PT, BT, BTG, BTP, BTI, NT, NTG, NTP, NTI, and RT) are reserved words and, thus, cannot be used as phrases in thesaurus entries.are the markers that indicate broader_termN is a broader (generic|partitive|instance) term for phrase.
broader_termN is a word or phrase that conceptually provides a more general description or category for phrase. For example, the word elephant could have a broader term of land mammal.
are the markers that indicate narrower_termN is a narrower (generic|partitive|instance) term for phrase.
If phrase does not have a broader (generic|partitive|instance) term, but has one or more narrower (generic|partitive|instance) terms, phrase is created as a top term in the respective hierarchy (in an Oracle Text thesaurus, the BT/NT, BTG/NTG, BTP/NTP, and BTI/NTI hierarchies are separate structures).
narrower_termN is a word or phrase that conceptually provides a more specific description for phrase. For example, the word elephant could have a narrower terms of indian elephant and african elephant.
is a marker that indicates phrase and synonymN are synonyms within a synonym ring.
synonymN is a word or phrase that has the same meaning for phrase. For example, the word dog could have a synonym of canine.
Note:
Synonym rings are not defined explicitly in Oracle Text thesauri. They are created by the transitive nature of synonyms.are markers that indicate phrase and synonym1 are synonyms within a synonym ring (similar to SYN).
The markers USE, SEE or PT also indicate synonym1 is the preferred term for the synonym ring. Any of these markers can be used to define the preferred term for a synonym ring.
is the marker that indicates related_termN is a related term for phrase.
related_termN is a word or phrase that has a meaning related to, but not necessarily synonymous with phrase. For example, the word dog could have a related term of wolf.
Note:
Related terms are not transitive. If a phrase has two or more related terms, the terms are related only to the parent phrase and not to each other.is the marker that indicates the following text is a scope note (for example, comment) for the preceding entry.
term is the translation of phrase into the language specified by language_key.
In compliance with thesauri standards, the load file supports formatting hierarchies (BT/NT, BTG/NTG, BTP, NTP, BTI/NTI) by indenting the terms under the top term and using NT (or NTG, NTP, NTI) markers that include the level for the term:
phrase NT1 narrower_term1 NT2 narrower_term1.1 NT2 narrower_term1.2 NT3 narrower_term1.2.1 NT3 narrower_term1.2.2 NT1 narrower_term2 . . . NT1 narrower_termN
Using this method, the entire branch for a top term can be represented hierarchically in the load file.
The following conditions apply to the structure of the entries in the import file:
each entry (phrase, BT, NT, or SYN) must be on a single line followed by a newline character
entries can consist of a single word or phrases
the maximum length of an entry (phrase, BT, NT, or SYN) is 255 bytes, not including the BT, NT, and SYN markers or the newline characters
entries cannot contain parentheses or plus signs.
each line of the file that starts with a relationship (BT, NT, and so on) must begin with at least one space
a phrase can occur more than once in the file
each phrase can have one or more narrower term entries (NT, NTG, NTP), broader term entries (BT, BTG, BTP), synonym entries, and related term entries
each broader term, narrower term, synonym, and preferred term entry must start with the appropriate marker and the markers must be in capital letters
the broader terms, narrower terms, and synonyms for a phrase can be in any order
homographs must be followed by parenthetical disambiguators everywhere they are used
For example: cranes (birds), cranes (lifting equipment)
compound terms are signified by a plus sign between each factor (for example. buildings + construction)
compound terms are allowed only as synonyms or preferred terms for other terms, never as terms by themselves, or in hierarchical relations.
terms can be followed by a scope note (SN), total maximum length of 2000 bytes, on subsequent lines
multi-line scope notes are allowed, but require an SN marker on each line of the note
Example of Incorrect SN usage:
VIEW CAMERAS SN Cameras with through-the lens focusing and a range of movements of the lens plane relative to the film plane
Example of Correct SN usage:
VIEW CAMERAS SN Cameras with through-the lens focusing and a SN range of movements of the lens plane relative SN to the film plane
Multi-word terms cannot start with reserved words (for example, use is a reserved word, so use other door is not an allowed term; however, use is an allowed term)
The following conditions apply to the relationships defined for the entries in the import file:
related term entries must follow a phrase or another related term entry
related term entries start with one or more spaces, the RT marker, followed by white space, then the related term on the same line
multiple related terms require multiple RT markers
Example of incorrect RT usage:
MOVING PICTURE CAMERAS RT CINE CAMERAS TELEVISION CAMERAS
Example of correct RT usage:
MOVING PICTURE CAMERAS RT CINE CAMERAS RT TELEVISION CAMERAS
Terms are allowed to have multiple broader terms, narrower terms, and related terms
This section provides three examples of correctly formatted thesaurus import files.
cat SYN feline NT domestic cat NT wild cat BT mammal mammal BT animal domestic cat NT Persian cat NT Siamese cat wild cat NT tiger tiger NT Bengal tiger dog BT mammal NT domestic dog NT wild dog SYN canine domestic dog NT German Shepard wild dog NT Dingo
animal
NT1 mammal
NT2 cat
NT3 domestic cat
NT4 Persian cat
NT4 Siamese cat
NT3 wild cat
NT4 tiger
NT5 Bengal tiger
NT2 dog
NT3 domestic dog
NT4 German Shepard
NT3 wild dog
NT4 Dingo
cat
SYN feline
dog
SYN canine
35MM CAMERAS BT MINIATURE CAMERAS CAMERAS BT OPTICAL EQUIPMENT NT MOVING PICTURE CAMERAS NT STEREO CAMERAS LAND CAMERAS USE VIEW CAMERAS VIEW CAMERAS SN Cameras with through-the lens focusing and a range of SN movements of the lens plane relative to the film plane UF LAND CAMERAS BT STILL CAMERAS
