Oracle® interMedia Reference 10g Release 2 (10.2) Part Number B14297-01 |
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Oracle interMedia ("interMedia") contains the following information about the ORDDoc object type:
The examples in this chapter use the ONLINE_MEDIA table in the Product Media sample schema. To replicate the examples on your own computer, you should begin with the examples shown in the reference pages for the ORDDoc constructors and the import( ) and importFrom( ) methods. Substitute files you have for the ones shown in the examples. In addition, for a user "ron" to use the examples, the following statements must be issued before ron executes the examples, where "/mydir/work" is the directory where ron will find the image, audio, and video data:
CONNECT /as sysdba CREATE OR REPLACE DIRECTORY FILE_DIR as '/mydir/work'; GRANT READ ON DIRECTORY FILE_DIR TO 'user';
See Oracle Database Sample Schemas for information about the sample schemas.
Note:
If you manipulate the media data itself (by either directly modifying the BLOB or changing the external source), then you must ensure that the object attributes stay synchronized and the update time is modified; otherwise, the object attributes will not match the media data.Methods invoked at the ORDSource level that are handed off to the source plug-in for processing have ctx (RAW) as the first argument. Before calling any of these methods for the first time, the client should allocate the ctx structure, initialize it to NULL, and invoke the openSource( ) method. At this point, the source plug-in can initialize context for this client. When processing is complete, the client should invoke the closeSource( ) method.
Methods invoked from a source plug-in call have the first argument as ctx (RAW).
Methods invoked at the ORDDoc level that are handed off to the format plug-in for processing have ctx (RAW) as the first argument. Before calling any of these methods for the first time, the client should allocate the ctx structure and initialize it to NULL.
Note:
In the current release, none of the plug-ins provided by Oracle and not all source or format plug-ins will use the ctx argument, but if you code as previously described, your application should work with current or future source or format plug-ins.You should use any of the individual set methods to set the attribute value for an object for formats not natively supported; otherwise, for formats natively supported, use the setProperties( ) method to populate the attributes of the object or write a format plug-in.
The ORDDoc object type supports the storage and management of any media data including image, audio, and video. This object type is defined as follows in the orddspec.sql
file:
CREATE OR REPLACE TYPE ORDDoc AS OBJECT ( -- ATTRIBUTES source ORDSource, format VARCHAR(80), mimeType VARCHAR(80), contentLength INTEGER, comments CLOB, -- METHODS -- CONSTRUCTORS -- STATIC FUNCTION init( ) RETURN ORDDoc, STATIC FUNCTION init(srcType IN VARCHAR2, srcLocation IN VARCHAR2, srcName IN VARCHAR2) RETURN ORDDoc, -- -- Methods associated with the mimeType attribute MEMBER FUNCTION getMimeType RETURN VARCHAR2, PRAGMA RESTRICT_REFERENCES(getMimeType, WNDS, WNPS, RNDS, RNPS), MEMBER PROCEDURE setMimeType(mime IN VARCHAR2), -- -- Methods associated with the date attribute MEMBER FUNCTION getUpdateTime RETURN DATE, PRAGMA RESTRICT_REFERENCES(getUpdateTime, WNDS, WNPS, RNDS, RNPS), MEMBER PROCEDURE setUpdateTime(current_time DATE), -- -- Methods associated with the format attribute MEMBER FUNCTION getFormat RETURN VARCHAR2, PRAGMA RESTRICT_REFERENCES(getFormat, WNDS, WNPS, RNDS, RNPS), MEMBER PROCEDURE setFormat(format IN VARCHAR2), -- -- Methods associated with the source attribute MEMBER FUNCTION isLocal RETURN BOOLEAN, PRAGMA RESTRICT_REFERENCES(isLocal, WNDS, WNPS, RNDS, RNPS), MEMBER PROCEDURE setLocal( ), MEMBER PROCEDURE clearLocal( ), -- MEMBER PROCEDURE setSource(source_type IN VARCHAR2, source_location IN VARCHAR2, source_name IN VARCHAR2), MEMBER FUNCTION getSource RETURN VARCHAR2, PRAGMA RESTRICT_REFERENCES(getSource, WNDS, WNPS, RNDS, RNPS), -- MEMBER FUNCTION getSourceType RETURN VARCHAR2, PRAGMA RESTRICT_REFERENCES(getSourceType, WNDS, WNPS, RNDS, RNPS), -- MEMBER FUNCTION getSourceLocation RETURN VARCHAR2, PRAGMA RESTRICT_REFERENCES(getSourceLocation, WNDS, WNPS, RNDS, RNPS), -- MEMBER FUNCTION getSourceName RETURN VARCHAR2, PRAGMA RESTRICT_REFERENCES(getSourceName, WNDS, WNPS, RNDS, RNPS), -- MEMBER PROCEDURE setProperties(ctx IN OUT RAW, setComments IN BOOLEAN), -- MEMBER FUNCTION getBFILE RETURN BFILE, PRAGMA RESTRICT_REFERENCES(getBFILE, WNDS, WNPS, RNDS, RNPS), -- MEMBER PROCEDURE import(ctx IN OUT RAW, set_prop IN BOOLEAN), MEMBER PROCEDURE importFrom(ctx IN OUT RAW, source_type IN VARCHAR2, source_location IN VARCHAR2, source_name IN VARCHAR2 set_prop IN BOOLEAN), -- MEMBER PROCEDURE export(ctx IN OUT RAW, source_type IN VARCHAR2, source_location IN VARCHAR2, source_name IN VARCHAR2), -- MEMBER FUNCTION openSource(userArg IN RAW, ctx OUT RAW) RETURN INTEGER, -- MEMBER FUNCTION closeSource(ctx IN OUT RAW) RETURN INTEGER, -- MEMBER FUNCTION trimSource(ctx IN OUT RAW, newlen IN INTEGER) RETURN INTEGER, -- MEMBER PROCEDURE readFromSource(ctx IN OUT RAW, startPos IN INTEGER, numBytes IN OUT INTEGER, buffer OUT RAW), -- MEMBER PROCEDURE writeToSource(ctx IN OUT RAW, startPos IN INTEGER, numBytes IN OUT INTEGER, buffer IN RAW), -- MEMBER FUNCTION getContentLength RETURN INTEGER, PRAGMA RESTRICT_REFERENCES(getContentLength, WNDS, WNPS, RNDS, RNPS), -- MEMBER PROCEDURE getContentInLob(ctx IN OUT RAW, dest_lob IN OUT NOCOPY BLOB, mimeType OUT VARCHAR2, format OUT VARCHAR2), -- MEMBER FUNCTION getContent RETURN BLOB, PRAGMA RESTRICT_REFERENCES(getContent, WNDS, WNPS, RNDS, RNPS), -- MEMBER PROCEDURE deleteContent( ), -- -- Methods associated with file operations on the source MEMBER FUNCTION processSourceCommand( ctx IN OUT RAW, cmd IN VARCHAR2, arguments IN VARCHAR2, result OUT RAW) RETURN RAW );
where:
source: the ORDSource where the media data is found.
format: the format in which the media data is stored.
mimeType: the MIME type information.
contentLength: the length of the media data stored in the source.
comments: the metadata information of the media object.
Note:
The comments attribute is populated by the setProperties( ) method when the setComments parameter is TRUE. Oracle recommends that you not write to this attribute directly.This section describes the ORDDoc constructor functions, which are the following:
init( ) RETURN ORDDoc;
Initializes instances of the ORDDoc object type.
None.
None.
None.
This constructor is a static method that initializes all the ORDDoc attributes to NULL with the following exceptions:
source.updateTime is set to SYSDATE
source.local is set to 1 (local)
source.localData is set to empty_blob
You should begin using the init( ) method as soon as possible so you can more easily initialize the ORDDoc object type, especially if the ORDDoc type evolves and attributes are added in a future release. INSERT statements left unchanged using the default constructor (which initializes each object attribute), will fail under these circumstances.
Initialize the ORDDoc object attributes:
BEGIN INSERT INTO pm.online_media (product_id, product_testimonials) VALUES (2808,ORDSYS.ORDDoc.init()); COMMIT; END; /
init(srcType IN VARCHAR2,
srcLocation IN VARCHAR2,
srcName IN VARCHAR2)
RETURN ORDDoc;
Initializes instances of the ORDDoc object type.
The source type of the media data.
The source location of the media data.
The source name of the media data.
None.
None.
This constructor is a static method that initializes all the ORDDoc attributes to NULL with the following exceptions:
source.updateTime is set to SYSDATE
source.local is set to 0
source.localData is set to empty_blob
source.srcType is set to the input value
source.srcLocation is set to the input value
source.srcName is set to the input value
You should begin using the init( ) method as soon as possible to allow you to more easily initialize the ORDDoc object type, especially if the ORDDoc type evolves and attributes are added in a future release. INSERT statements left unchanged using the default constructor (which initializes each object attribute), will fail under these circumstances.
Initialize the ORDDoc object attributes:
BEGIN INSERT INTO pm.online_media (product_id, product_testimonials) VALUES (2999, ORDSYS.ORDDoc.init('file', 'FILE_DIR', 'modem.jpg')); END; /
This section presents reference information on the interMedia methods used specifically for media data manipulation.
Chapter 2 presents reference information on the interMedia methods that are common to ORDAudio, ORDDoc, ORDImage, and ORDVideo. Use the methods presented in both chapters to get and set attributes, and to perform metadata extractions.
For more information about object types and methods, see Oracle Database Concepts.
getContentInLob(ctx IN OUT RAW,
dest_lob IN OUT NOCOPY BLOB,
mimeType OUT VARCHAR2,
format OUT VARCHAR2);
Copies data from a data source into the specified BLOB. The BLOB must not be the BLOB in the source.localData attribute (of the embedded ORDSource object).
The source plug-in context information.
The LOB in which to receive data.
The MIME type of the data; this may or may not be returned.
The format of the data; this may or may not be returned.
None.
None.
ORDDocExceptions.NULL_SOURCE
This exception is raised when the value of the ORDDoc.source attribute is NULL.
ORDSourceExceptions.METHOD_NOT_SUPPORTED
This exception is raised if you call the getContentInLob( ) method and this method is not supported by the source plug-in being used.
See Appendix G for more information about these exceptions.
Get data from a data source and put it into the specified BLOB:
DECLARE obj ORDSYS.ORDDoc; tempBLob BLOB; mimeType VARCHAR2(4000); format VARCHAR2(31); ctx RAW(64) :=NULL; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id = 2808 ; IF (obj.isLocal()) THEN DBMS_OUTPUT.put_line('Local is true'); END IF; DBMS_LOB.CREATETEMPORARY(tempBLob, true, 10); obj.getContentInLob(ctx,tempBLob, mimeType,format); DBMS_OUTPUT.PUT_LINE('Length: ' || TO_CHAR(DBMS_LOB.getLength(tempBLob))); EXCEPTION WHEN ORDSYS.ORDSourceExceptions.METHOD_NOT_SUPPORTED THEN DBMS_OUTPUT.put_line('ORDSourceExceptions.METHOD_NOT_SUPPORTED caught'); WHEN OTHERS THEN DBMS_OUTPUT.put_line('EXCEPTION caught'); END; /
getContentLength( ) RETURN INTEGER;
Returns the length of the media data content stored in the source.
None.
None.
PRAGMA RESTRICT_REFERENCES(getContentLength, WNDS, WNPS, RNDS, RNPS)
ORDDocExceptions.NULL_SOURCE
This exception is raised when the value of the ORDDoc.source attribute is NULL.
See Appendix G for more information about this exception.
DECLARE obj ORDSYS.ORDDoc; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id = 2808 ; IF (obj.isLocal()) THEN DBMS_OUTPUT.put_line('Local is true'); END IF; DBMS_OUTPUT.PUT_LINE('Content length is ' || TO_CHAR(obj.getContentLength)); END;/
getFormat( ) RETURN VARCHAR2;
Returns the value of the format attribute of the media object.
None.
None.
PRAGMA RESTRICT_REFERENCES(getFormat, WNDS, WNPS, RNDS, RNPS)
ORDDocExceptions.INVALID_FORMAT_TYPE
This exception is raised if you call the getFormat( ) method and the value of the format attribute is NULL.
See Appendix G for more information about this exception.
See the example in setFormat( ).
import(ctx IN OUT RAW
set_prop IN BOOLEAN);
Transfers media data from an external media data source to the source.localData attribute (of the embedded ORDSource object) within the database.
The source plug-in context information. This should be allocated and initialized to NULL. If you are using a user-defined source plug-in, you should call the openSource( ) method. See the introduction to this chapter for more information.
A value that determines whether the setProperties( ) method is called. If the value of this parameter is TRUE, then the setProperties( ) method is called to read the media data to get the values of the object attributes and store them in the object attributes; otherwise, if the value is FALSE, the set Properties( ) method is not called. The default value is FALSE.
Use the setSource( ) method to set the source.srcType, source.srcLocation, and source.Name attributes (of the embedded ORDSource object) for the external media data source prior to calling the import( ) method.
After importing data from an external media data source to a local source (within Oracle Database), the source information remains unchanged (that is, pointing to the source from where the data was imported).
Invoking this method implicitly calls the setUpdateTime( ) and setLocal( ) methods.
This method is invoked at the ORDSource level, which uses the PL/SQL UTL_HTTP package to import media data from an HTTP data source. You can use environment variables to specify the proxy behavior of the UTL_HTTP package. For example, on UNIX, setting the environment variable http_proxy to a URL specifies that the UTL_HTTP package will use that URL as the proxy server for HTTP requests. Setting the no_proxy environment variable to a domain name specifies that the HTTP proxy server will not be used for URLs in the specified domain.
See Oracle Database PL/SQL Packages and Types Reference for more information about the UTL_HTTP PL/SQL package.
None.
ORDDocExceptions.NULL_SOURCE
This exception is raised when the value of the ORDDoc.source attribute is NULL.
ORDSourceExceptions.INCOMPLETE_SOURCE_INFORMATION
This exception is raised if you call the import( ) method and the value of the source.srcType attribute is NULL.
ORDSourceExceptions.METHOD_NOT_SUPPORTED
This exception is raised if you call the import( ) method and the import( ) method is not supported by the source plug-in being used.
ORDSourceExceptions.NULL_SOURCE
This exception is raised if you call the import( ) method and the value of the source.localData attribute is NULL.
ORDSYS.ORDDocExceptions.DOC_PLUGIN_EXCEPTION
This exception is raised if you call the import( ) method and the setProperties( ) method raises an exception from within the media plug-in.
See Appendix G for more information about these exceptions.
Import media data from an external media data source into the local source:
DECLARE obj ORDSYS.ORDDoc; ctx RAW(64) :=NULL; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id = 2808 FOR UPDATE; DBMS_OUTPUT.PUT_LINE('setting and getting source'); DBMS_OUTPUT.PUT_LINE('--------------------------'); -- set source to a file obj.setSource('file','FILE_DIR','printer.rm'); -- get source information DBMS_OUTPUT.PUT_LINE(obj.getSource()); -- import data obj.import(ctx,FALSE); -- check size DBMS_OUTPUT.PUT_LINE('Length:' ||TO_CHAR(DBMS_LOB.getLength(obj.getContent))); UPDATE pm.online_media SET product_testimonials=obj WHERE product_id=2808; COMMIT; EXCEPTION WHEN ORDSYS.ORDSourceExceptions.METHOD_NOT_SUPPORTED THEN DBMS_OUTPUT.PUT_LINE('ORDSourceExceptions.METHOD_NOT_SUPPORTED caught'); WHEN ORDSYS.ORDDocExceptions.DOC_PLUGIN_EXCEPTION THEN DBMS_OUTPUT.put_line('DOC PLUGIN EXCEPTION caught'); END; /
importFrom(ctx IN OUT RAW,
source_type IN VARCHAR2,
source_location IN VARCHAR2,
source_name IN VARCHAR2
set_prop IN BOOLEAN);
Transfers media data from the specified external media data source to the source.localData attribute (of the embedded ORDSource object) within the database).
The source plug-in context information. This should be allocated and initialized to NULL. If you are using a user-defined source plug-in, you should call the openSource( ) method. See the introduction to this chapter for more information.
The type of the source media data.
The location from which the source media data is to be imported.
The name of the source media data.
A value that determines whether the setProperties( ) method is called. If the value of this parameter is TRUE, then the setProperties( ) method is called to read the media data to get the values of the object attributes and store them in the object attributes; otherwise, if the value is FALSE, the set Properties( ) method is not called. The default value is FALSE.
This method is similar to the import( ) method except the source information is specified as parameters to the method instead of separately.
You must ensure that the directory indicated by the source_location parameter exists or is created before you use this method.
After importing data from an external media data source to a local source (within Oracle Database), the source information (that is, pointing to the source from where the data was imported) is set to the input values.
Invoking this method implicitly calls the setUpdateTime( ) and setLocal( ) methods.
This method is invoked at the ORDSource level, which uses the PL/SQL UTL_HTTP package to import media data from an HTTP data source. You can use environment variables to specify the proxy behavior of the UTL_HTTP package. For example, on UNIX, setting the environment variable http_proxy to a URL specifies that the UTL_HTTP package will use that URL as the proxy server for HTTP requests. Setting the no_proxy environment variable to a domain name specifies that the HTTP proxy server will not be used for URLs in the specified domain.
See Oracle Database PL/SQL Packages and Types Reference for more information about the UTL_HTTP PL/SQL package.
None.
ORDDocExceptions.NULL_SOURCE
This exception is raised when the value of the ORDDoc.source attribute is NULL.
ORDSourceExceptions.INCOMPLETE_SOURCE_INFORMATION
This exception is raised if you call the importFrom( ) method and the value of the source_type parameter is NULL.
ORDSourceExceptions.METHOD_NOT_SUPPORTED
This exception is raised if you call the importFrom( ) method and this method is not supported by the source plug-in being used.
ORDSYS.ORDDocExceptions.DOC_PLUGIN_EXCEPTION
This exception is raised if you call the importFrom( ) method and the setProperties( ) method raises an exception from within the media plug-in.
See Appendix G for more information about these exceptions.
Import media data from the specified external data source into the local source:
DECLARE obj ORDSYS.ORDDoc; ctx RAW(64) :=NULL; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id=2999 FOR UPDATE; DBMS_OUTPUT.PUT_LINE('setting and getting source'); DBMS_OUTPUT.PUT_LINE('--------------------------'); -- set source to a file -- import data obj.importFrom(ctx,'file','FILE_DIR','modem.jpg',FALSE); -- check size DBMS_OUTPUT.PUT_LINE('Length: '||TO_CHAR(DBMS_LOB.GETLENGTH(obj.getContent))); DBMS_OUTPUT.PUT_LINE(obj.getSource()); UPDATE pm.online_media SET product_testimonials=obj WHERE product_id=2999; COMMIT; EXCEPTION WHEN ORDSYS.ORDSourceExceptions.METHOD_NOT_SUPPORTED THEN DBMS_OUTPUT.PUT_LINE('ORDSourceExceptions.METHOD_NOT_SUPPORTED caught'); WHEN ORDSYS.ORDDocExceptions.DOC_PLUGIN_EXCEPTION THEN DBMS_OUTPUT.put_line('DOC PLUGIN EXCEPTION caught'); END; /
setFormat(knownFormat IN VARCHAR2);
Sets the format attribute of the media object.
The known format of the data to be set in the corresponding media object.
Calling this method implicitly calls the setUpdateTime( ) method.
None.
ORDDocExceptions.NULL_INPUT_VALUE
This exception is raised if you call the setFormat( ) method and the value for the knownFormat parameter is NULL.
ORDDocExceptions.NULL_SOURCE
This exception is raised when the value of the ORDDoc.source attribute is NULL.
See Appendix G for more information about these exceptions.
Set the format for some media data:
DECLARE obj ORDSYS.ORDDoc; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id = 2808 FOR UPDATE; obj.setFormat('PDF'); DBMS_OUTPUT.put_line('format: ' || obj.getformat()); COMMIT; EXCEPTION WHEN ORDSYS.ORDDocExceptions.NULL_INPUT_VALUE THEN DBMS_OUTPUT.put_line('ORDDocExceptions.NULL_INPUT_VALUE caught'); WHEN OTHERS THEN DBMS_OUTPUT.put_line('EXCEPTION caught'); END; /
setProperties(ctx IN OUT RAW,
setComments IN BOOLEAN);
Reads the media data to get the values of the object attributes and then stores them in the object attributes. This method sets the properties for the following attributes of the media data: format, MIME type, and content length. It populates the comments field of the object with an extensive set of format and application properties in XML form if the value of the setComments parameter is TRUE.
Note:
This method works for only natively supported audio, image, and video formats. See Appendix A, Appendix B, and Appendix C for information about natively supported audio, image, and video formats.The format plug-in context information.
A Boolean value that indicates whether or not the comments field of the object is populated. If the value is TRUE, then the comments field of the object is populated with an extensive set of format and application properties of the media object in XML form; otherwise, if the value is FALSE, the comments field of the object remains unpopulated. The default value is FALSE.
If the property cannot be extracted from the media source, then the respective attribute is set to NULL.
If the format attribute is set to NULL, then the setProperties( ) method uses the default format plug-in; otherwise, it uses the plug-in specified by the format.
None.
ORDDocExceptions.DOC_PLUGIN_EXCEPTION
This exception is raised if you call the setProperties( ) method and the media plug-in raises an exception.
ORDDocExceptions.NULL_SOURCE
This exception is raised when the value of the ORDDoc.source attribute is NULL.
See Appendix G for more information about these exceptions.
Set the property information for known media attributes:
DECLARE obj ORDSYS.ORDDoc; ctx RAW(64) :=NULL; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id = 2808 FOR UPDATE; obj.setProperties(ctx,FALSE); DBMS_OUTPUT.put_line('format: ' || obj.getformat()); UPDATE pm.online_media SET product_testimonials = obj WHERE product_id=2808; COMMIT; EXCEPTION WHEN ORDSYS.ORDDocExceptions.DOC_PLUGIN_EXCEPTION THEN DBMS_OUTPUT.put_line('DOC PLUGIN EXCEPTION caught'); WHEN OTHERS THEN DBMS_OUTPUT.put_line('EXCEPTION caught'); END; /
Set the property information for known media attributes and store the format and application properties in the comments attribute. Create an extensible index on the contents of the comments attribute using Oracle Text:
DECLARE obj ORDSYS.ORDDoc; ctx RAW(64) :=NULL; BEGIN SELECT product_testimonials INTO obj FROM pm.online_media WHERE product_id = 2999 FOR UPDATE; obj.setProperties(ctx,TRUE); DBMS_OUTPUT.put_line('format: ' || obj.getformat()); UPDATE pm.online_media SET product_testimonials = obj WHERE product_id=2999; COMMIT; EXCEPTION WHEN ORDSYS.ORDDocExceptions.DOC_PLUGIN_EXCEPTION THEN DBMS_OUTPUT.put_line('DOC PLUGIN EXCEPTION caught'); WHEN OTHERS THEN DBMS_OUTPUT.put_line('EXCEPTION caught'); END; / CONNECT / AS SYSDBA -- Must have Oracle Text installed on your system. CREATE INDEX mediaindex ON pm.online_media(product_testimonials.comments) INDEXTYPE IS ctxsys.context;