Oracle® Text Application Developer's Guide 10g Release 2 (10.2) Part Number B14217-01 |
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This chapter covers issues relating to migrating your applications from previous releases of Oracle Text. It consists of two sections:
Migrating to Oracle Text 10g Release 2 (10.2) describes factors to consider when upgrading to the current release of Oracle Text.
Migrating to Oracle Text 10g Release 1 (10.1) is provided for those users who may be upgrading from the next-to-last release of Oracle Text and who want to know what migration steps were required to upgrade to the last release.
This section covers issues relating to migrating your applications to Oracle Text 10g Release 2 (10.2).
For Oracle Text 10g Release 2, the INSO_FILTER
filter type has been replaced by the AUTO_FILTER
filter type. To maintain compatibility with existing Oracle Text applications, INSO_FILTER
functionality is supported by AUTO_FILTER
, and the INSO_FILTER
filter type is being retained, although its behavior has been changed to match that of AUTO_FILTER
.
For most users, the change in filter types will have no significant effect, and most users will not have to change their applications or otherwise take any steps to migrate to the new filter type. The most significant differences produced by this change are as follows:
AUTO_FILTER
supports a different set of document types than INSO_FILTER
. For a list of supported document types, see the Supported File Formats appendix of the Oracle Text Reference.
Display characteristics of HTML output from the new filter may differ from those output by the old filter.
A different set of platforms support the AUTO_FILTER
type than support INSO_FILTER
. For a list of supported platforms, see the Supported File Formats appendix of the Oracle Text Reference.
Along with the change from INSO_FILTER
to AUTO_FILTER
, several related changes are also part of the filter migration:
The INSO_TIMEOUT
and INSO_OUTPUT_FORMATTING
attributes of MAIL_FILTER
have been replaced by the AUTO_FILTER_TIMEOUT
and AUTO_FILTER_OUTPUT_FORMATTING
attributes, respectively.
The INSOFILTER
directive used in the mail configuration file of MAIL_FILTER
has been replaced with the AUTO_FILTER
directive.
The PL/SQL constant TRACE_IDX_INSO_FILTER
for tracing, used in procedures such as CTX_OUTPUT.ADD_TRACE
, has been replaced by the TRACE_IDX_AUTO_FILTER
filter.
The system-defined preference CTXSYS.INSO_FILTER
has been replaced by the CTXSYS.AUTO_FILTER
preference.
The default values of DEFAULT_FILTER_FILE
and DEFAULT_FILTER_BINARY
system parameters has been changed from CTXSYS.INSO_FILTER
to CTXSYS.AUTO_FILTER
for new installations and databases upgrading to this release, if these default values have not been modified. For databases upgrading to this release which have modified these default values, the modified default values will continue to be used.
For backward compatibility, INSO_FILTER
, as well as most of its associated filter types, constants, and attributes have been retained in this release; however, users should use AUTO_FILTER
in new applications and update their older applications whenever possible.
Most applications will not have to be modified to reflect the change to the AUTO_FILTER
type. The following migration steps will be performed automatically when you upgrade to this release:
If an existing index uses the INSO_FILTER
filter type, then it will be migrated to the AUTO_FILTER
filter type.
If an existing index uses the MAIL_FILTER
filter type, then the INSO_TIMEOUT
and INSO_OUTPUT_FORMATTING
attributes will be migrated to the AUTO_FILTER_TIMEOUT
nd AUTO_FILTER_OUTPUT_FORMATTING
attributes, respectively.
If the default values of the system parameters DEFAULT_FILTER_FILE
and DEFAULT_FILTER_BINARY
have not already been modified, then they will be migrated from CTXSYS.INSO_FILTER
to CTXSYS.AUTO_FILTER
.
Although no actions are required to migrate to the new filter system, Oracle Text users upgrading their databases to this release should take the following steps to migrate away from using APIs deprecated by this release:
If an index uses the MAIL_FILTER
filter type with a nondefault mail configuration file, edit the file, replacing all occurrences of the INSOFILTER
directive with the AUTO_FILTER
directive.
Replace the use of the PL/SQL constant TRACE_IDX_INSO_FILTER
in your application with the TRACE_IDX_AUTO_FILTER
constant.
Replace the use of the system-defined preference CTXSYS.INSO_FILTER
in your applications with CTXSYS.AUTO_FILTER
.
This section covers issues relating to migrating your applications to Oracle Text 10g Release 1 (10.1). It also contains a note on migrating back from release 10.1.
In releases of Oracle Text previous to 10g Release 1, CTXSYS
had DBA privileges. To tighten security and protect the database in the case of unauthorized access, CTXSYS
now has only CONNECT
and RESOURCE
roles, and only limited, necessary direct grants on some system views and packages. Some applications using Oracle Text may therefore require minor changes in order to work properly with this security change. Here are the major effects of the security improvements, their possible effects on Oracle Text applications, and the steps needed to ensure proper operation in Oracle Database 10g.
CTXSYS
no longer has DBA permissions. This may affect indexes using USER_DATASTORE
, PROCEDURE_FILTER
, or USER_LEXER
objects. For example, suppose that you have an index using a USER_DATASTORE
whose procedure is CTXSYS.PROC
, and that procedure refers to other schemas' objects:
create procedure proc(r in rowid, d in out nocopy clob) is begin select text into l_data from scott.example ...
Previously, this user datastore would have worked properly because CTXSYS
was able to select from any table—namely, SCOTT.EXAMPLE
. However, in Oracle Database 10g, CTXSYS
does not have DBA privileges and is not allowed to select from SCOTT.EXAMPLE
. This makes the procedure PROC invalid, which leads to errors when indexing or sync is done for this index.
To resolve this problem, Oracle recommends migrating all user datastores, procedure filters, and user lexers from CTXSYS
-owned procedures to index-owner-owned procedures (see "Migrating CTXSYS-Owned Procedures").
Here are the steps to migrate an index using a CTXSYS
-owned procedure to use an index-owner-owned procedure:
Create a procedure owned by the index owner that is equivalent to the CTXSYS
-owned procedure. If your application's CTXSYS
-owned procedure simply calls another procedure owned by the index owner, use that procedure for step 2. Otherwise, copy the code from the CTXSYS
-owned procedure into a new procedure owned by the index owner, making any needed changes for the change in schema.
Create a new user datastore, procedure filter, or user lexer preference that uses the index-owner-owned procedure. Alternatively, you can modify the existing preference using CTX_DDL.SET_ATTRIBUTE
, if the preference used to create the index still exists.
Replace the existing datastore or filter or lexer with the new, updated preference using the new REPLACE METADATA
command. For instance, to replace a user datastore:
alter index <myindex> rebuild parameters ('replace metadata datastore <new_datastore_preference>');
REPLACE METADATA
does not rebuild the index, so this command will not affect existing index data.
In previous releases of Oracle Text, the effective user during indexing or sync was CTXSYS
. As a result, CTXSYS
required execute permission on all BFILE directories, execute permission on any procedures called from user datastores, procedure filters, or user lexers, and the CTXSYS
user's TEMP
tablespace was used during indexing. In Oracle Database 10g, the effective user during indexing is the index owner, which eliminates these caveats.
Previously, procedures used in user datastores, procedure filters, and user lexers had to be owned by CTXSYS
. In Oracle Database 10g, these procedures can be owned by any schema, so long as the index owner has execute privileges on them.
This principally affects creation of preferences. In previous releases of Oracle Text, a user datastore created with:
beginctx_ddl.create_preference('example','user_datastore');ctx_ddl.set_attribute('example','procedure','proc');end;
would have used the procedure CTXSYS.PROC
. However, in Oracle Database 10g, standard Oracle Database rules are applied to the input "PROC," and this resolves to USER.PROC
. Any application code that creates user datastores, procedure filters, or user lexers should either create the preferences as the owner of the procedure, or prepend the correct owner name to the procedure name. For example:
ctx_ddl.set_attribute('example','procedure','user.proc');
In previous releasess of Oracle Text, only the owner of the index and CTXSYS
were allowed to sync or optimize an index through CTX_DDL.SYNC_INDEX
and CTX_DDL.OPTIMIZE_INDEX
. In Oracle Database 10g, any user with the ALTER ANY INDEX
system privilege is also allowed to sync or optimize any index.
Most public CTX packages, such as CTX_DDL
, CTX_QUERY
, and CTX_REPORT
, are now invoker's rights packages.
In Oracle Database 10g, if a text index is created by one user for another user, or if the create index statement is issued from a PL/SQL block, the index owner must be granted the CREATE TABLE
privilege in order for the indexing to succeed. Even if the index owner has the RESOURCE
role, CREATE TABLE
must be specifically granted.
During the upgrade to Oracle Database 10g, Oracle Text drops a number of procedures belonging to CTXSYS
. (These procedures are invalid under Oracle Database 10g and have the name format DR$
indexid$U
.) If you migrate back to a pre-10g release of Oracle Database, you must re-create these procedures in order for DML to work. To do this, after the backward migration—once all the pre-10g packages have been reinstalled—rename each CTXCAT
index; the rename code will re-create that procedure. (You can rename the procedures back if you want to retain the original names).