Administering Oracle Text

17.1 Oracle Text Users and Roles

While any user can create an Oracle Text index and enter a CONTAINS query, Oracle Text provides the CTXSYS user for administration and the CTXAPP role for application developers.

This section contains the following sections:

17.1.1 CTXSYS User

The CTXSYS user is created during installation and can:

View all indexes
Sync all indexes
Run ctxkbtc, the knowledge base extension compiler
Query all system-defined views
Perform all tasks of a user with the CTXAPP role

Note:

In earlier releases of Oracle Text, CTXSYS had SYSDBA privileges, and only CTXSYS users could perform certain functions, such as modifying system-defined preferences or setting system parameters.

17.1.2 CTXAPP Role

The CTXAPP role is a system-defined role that enables users to:

Create and delete Oracle Text preferences
Use the Oracle Text PL/SQL packages

17.1.3 Granting Roles and Privileges to Users

The system uses the standard SQL model for granting roles to users. To grant an Oracle Text role to a user, use the GRANT statement.

In addition, to allow application developers to call procedures in the Oracle Text PL/SQL packages, you must explicitly grant EXECUTE privileges for the Oracle Text package to each user.

See Also:

"Creating an Oracle Text User"

17.2 DML Queue

When you make inserts, updates, or deletes to documents in your base table, the data manipulation language (DML) queue stores the requests for documents waiting to be indexed. When you synchronize the index with CTX_DDL.SYNC_INDEX, requests are removed from this queue.

You can query pending insert, update, and delete operations with the CTX_PENDING and CTX_USER_PENDING views.

You can query insert, update, and delete errors with the CTX_INDEX_ERRORS or CTX_USER_INDEX_ERRORS view.

See Also:

Oracle Text Reference for more information about these views

17.3 CTX_OUTPUT Package

Use the CTX_OUTPUT PL/SQL package to log indexing and document service requests.

See Also:

Oracle Text Reference for more information about this package

17.4 CTX_REPORT Package

Use the CTX_REPORT package to produce reports on indexes and queries. These reports can help you fine-tune or troubleshoot your applications.

See Also:

Oracle Text Reference for more information about this package

The CTX_REPORT package contains the following procedures:

CTX_REPORT.DESCRIBE_INDEX and CTX_REPORT.DESCRIBE_POLICY

These procedures create reports that describe an existing index or policy, including the settings of the index metadata, the indexing objects, the settings of the attributes of the objects, and (for CTX_REPORT.DESCRIBE_INDEX) the index partition information, if any. These procedures are especially useful for diagnosing index-related problems.

This is sample output from DESCRIBE_INDEX, run on a simple context index:

=================================================================
                        INDEX DESCRIPTION
=================================================================
index name:                      "DR_TEST"."TDRBPRX0"
index id:                        1160
index type:                      context
base table:                      "DR_TEST"."TDRBPR"
primary key column:              ID
text column:                     TEXT2
text column type:                VARCHAR2(80)
language column:
format column:
charset column:
=================================================================
                          INDEX OBJECTS
=================================================================
datastore:                       DIRECT_DATASTORE
filter:                          NULL_FILTER
section group:                   NULL_SECTION_GROUP
lexer:                           BASIC_LEXER
wordlist:                        BASIC_WORDLIST
   stemmer:                         ENGLISH
   fuzzy_match:                     GENERIC
stoplist:                        BASIC_STOPLIST
   stopword:                       teststopword
storage:                         BASIC_STORAGE
   r_table_clause:                  lob (data) store as (cache)
   i_index_clause:                  compress 2

CTX_REPORT.CREATE_INDEX_SCRIPT and CTX_REPORT.CREATE_POLICY_SCRIPT

CREATE_INDEX_SCRIPT creates a SQL*Plus script that can create a duplicate of a given Oracle Text index. Use this when you have an index but you do not have the original script (if any) that was used to create this index, and you want to be able to re-create the index. For example, if you accidentally drop a script, CREATE_INDEX_SCRIPT can re-create it. Likewise, CREATE_INDEX_SCRIPT can be useful if you have inherited indexes from another user but not the scripts that created them.

CREATE_POLICY_SCRIPT does the same thing as CREATE_INDEX_SCRIPT, except that it enables you to re-create a policy instead of an index.

This is sample output from CREATE_INDEX_SCRIPT, run on a simple context index (not a complete listing):

begin
  ctx_ddl.create_preference('"TDRBPRX0_DST"','DIRECT_DATASTORE');
end;
/
...
/
begin
  ctx_ddl.create_section_group('"TDRBPRX0_SGP"','NULL_SECTION_GROUP');
end;
/
...
begin
  ctx_ddl.create_preference('"TDRBPRX0_WDL"','BASIC_WORDLIST');
  ctx_ddl.set_attribute('"TDRBPRX0_WDL"','STEMMER','ENGLISH');
  ctx_ddl.set_attribute('"TDRBPRX0_WDL"','FUZZY_MATCH','GENERIC');
end;
/
begin
  ctx_ddl.create_stoplist('"TDRBPRX0_SPL"','BASIC_STOPLIST');
  ctx_ddl.add_stopword('"TDRBPRX0_SPL"','teststopword');
end;
/
...
/
begin
  ctx_output.start_log('TDRBPRX0_LOG');
end;
/
create index "DR_TEST"."TDRBPRX0"
  on "DR_TEST"."TDRBPR"
      ("TEXT2")
  indextype is ctxsys.context
  parameters('
    datastore       "TDRBPRX0_DST"
    filter          "TDRBPRX0_FIL"
    section group   "TDRBPRX0_SGP"
    lexer           "TDRBPRX0_LEX"
    wordlist        "TDRBPRX0_WDL"
    stoplist        "TDRBPRX0_SPL"
    storage         "TDRBPRX0_STO"
  ')
/

CTX_REPORT.INDEX_SIZE

This procedure creates a report of the names of the internal index objects, along with their tablespaces, allocated sizes, and used sizes. It is useful for DBAs who may need to monitor the size of their indexes (for example, when disk space is at a premium).

Sample output from this procedure looks like this (partial listing):

=================================================================
                INDEX SIZE FOR DR_TEST.TDRBPRX10
=================================================================
TABLE:                          DR_TEST.DR$TDRBPRX10$I
TABLESPACE NAME:                DRSYS
BLOCKS ALLOCATED:                                            4
BLOCKS USED:                                                 1
BYTES ALLOCATED:                               8,192 (8.00 KB)
BYTES USED:                                    2,048 (2.00 KB)

INDEX (LOB):                    DR_TEST.SYS_IL0000023161C00006$$
TABLE NAME:                     DR_TEST.DR$TDRBPRX10$I
TABLESPACE NAME:                DRSYS
BLOCKS ALLOCATED:                                            5
BLOCKS USED:                                                 2
BYTES ALLOCATED:                             10,240 (10.00 KB)
BYTES USED:                                    4,096 (4.00 KB)

INDEX (NORMAL):                 DR_TEST.DR$TDRBPRX10$X
TABLE NAME:                     DR_TEST.DR$TDRBPRX10$I
TABLESPACE NAME:                DRSYS
BLOCKS ALLOCATED:                                            4
BLOCKS USED:                                                 2
BYTES ALLOCATED:                               8,192 (8.00 KB)
BYTES USED:                                    4,096 (4.00 KB)

CTX_REPORT.INDEX_STATS

INDEX_STATS produces a variety of calculated statistics about an index, such as how many documents are indexed, how many unique tokens in the index, average size of its tokens, and fragmentation information for the index. Optimizing stoplists is an example of a use for INDEX_STATS.

CTX_REPORT.QUERY_LOG_SUMMARY

This procedure creates a report of logged queries, which you can use to perform simple analyses. With query analysis, you can find out:

Which queries were made
Which queries were successful
Which queries were unsuccessful
How many times each query was made

You can combine these factors in various ways, such as determining the 50 most frequent unsuccessful queries made by your application.

CTX_REPORT.TOKEN_INFO

TOKEN_INFO helps you diagnose query problems. For example, use it to check that index data is not corrupted and to find out which documents are producing unexpected or bad tokens.

CTX_REPORT.TOKEN_TYPE

TOKEN_TYPE is a lookup function that is used mainly as input to other functions (CTX_DDL.OPTIMIZE_INDEX, CTX_REPORT.TOKEN_INFO, and so on).

See Also:

Oracle Text Reference for an example of the output of CTX_REPORT.INDEX_STATS procedure
Oracle Text Reference for an example of the output of CTX_REPORT.QUERY_LOG_SUMMARY procedure

17.5 Text Manager in Oracle Enterprise Manager

Oracle Enterprise Manager provides Text Manager for configuring, maintaining, and administering Oracle Text indexes. With Text Manager, you can perform all of the basic configuration and administration tasks for Oracle Text indexes. You can monitor the overall health of Oracle Text indexes for a single Oracle Database instance or for the Oracle Real Application Clusters environment. Text Manager provides summaries of critical information and enables you to drill down to the level of detail that you want, to resolve issues, and to understand any actions that you need to take.

The Text Indexes page shows the jobs that are in progress, that are scheduled within the last seven days, or that are experiencing problems. From this page, you can go to the Job Scheduler to see a summary of all jobs for this database instance and to manage selected jobs. The online help in Oracle Enterprise Manager provides details and procedures for using each Text Manager feature.

This section contains the following sections:

Note:

You cannot create an Oracle Text index with Text Manager. Use the CREATE INDEX statement to create an Oracle Text index as described in Indexing with Oracle Text under Creating Oracle Text Indexes.

17.5.1 Using Text Manager

On the main Text Manager page, you can perform the following actions on the selected index from the Actions list:

Synchronize
Optimize
Rebuild
Resume Failed Operation
Show Logs
Show Errors

You can also schedule jobs for the specified index.

To access Text Manager:

Sign in to the database with a user account that is authorized to access Cloud Control. For example, use SYS or SYSTEM and the password that you specified during database installation.
On the Database Home page, click the Schema tab.
In the Text Manager group, select Text Indexes.

The Text Indexes page displays a list of Oracle Text indexes for this database instance.

When you select an Oracle Text index from the Text Indexes page, edit and action options become available for that index. For example, to configure attributes for searching, click Edit for the selected index. On the Edit Text Index page, you can set such attributes as Wild Card Maximum Term, Fuzzy Score, and Number of Fuzzy Expansions. You can also change index and partition names, and specify settings for URL_DATASTORE.

17.5.2 Viewing General Information for an Oracle Text Index

Use the View Text Index page to see general information about a specific index, such as index type, parallel degree, synchronization mode, wild card limit, fuzzy score, fuzzy numeric result, and datastore. Information about any partitions on the index is also available.

To view general information for an Oracle Text index, on the Text Indexes page, in the list of indexes, click the name of the index. The View Text Index page opens and the General tab is selected. From here, you can select actions to perform maintenance tasks.

17.5.3 Checking Oracle Text Index Health

In Text Manager, the Text Indexes page displays the Oracle Text indexes for the database instance. Use that page to help you understand the critical actions that are necessary to make sure that the entire application is performing properly.

Use the Text Indexes page to see:

The status of the indexes and jobs submitted during the last seven days.
The number of Oracle Text indexes that contain invalid partitions, and which are, therefore, invalid. The number of partitions that are invalid, if any, for all Oracle Text indexes is also shown.
The number of indexes and partitions that are in an in-progress state.
The number of indexes where all partitions are valid, and no activity is in progress.
The sum total of the Oracle Text indexes found for this database instance.
The index type for each Oracle Text index, the owner, the number of documents that are not synchronized, total number of documents, and percentage of fragmentation.

After you select an Oracle Text index from the list, options become available for editing or performing actions.

17.6 Servers and Indexing

You index documents and enter queries with standard SQL. No server is needed for performing batch insert, update, and delete operations. You can synchronize the CONTEXT index with the CTX_DDL.SYNC_INDEX procedure, or from Text Manager in Oracle Enterprise Manager.

See Also:

Indexing with Oracle Text for more information about indexing and index synchronization

17.7 Tracking Database Feature Usage in Oracle Enterprise Manager

In Oracle Enterprise Manager, Database Feature Usage statistics provide an approximation of how often various database features are used. Tracking this information is useful for application development and for auditing.

To access Database Feature Usage, in Oracle Enterprise Manager, click the Server tab, and then select Database Feature Usage under Database Configuration.

Database Feature Usage captures the following information for Oracle Text:

Index Usage Statistics: The number of existing indexes in the database for the CONTEXT, CTXCAT, and CTXRULE index types
SQL Operator Usage Statistics: Whether the user has ever used the CONTAINS, CATSEARCH, and MATCHES operators
Package Usage Statistics: How often, if ever, and when the following packages were used:
- CTX_ADM
- CTX_CLS
- CTX_DDL
- CTX_DOC
- CTX_OUTPUT
- CTX_QUERY
- CTX_REPORT
- CTX_THES
- CTX_ULEXER

Note:

The feature usage tracking statistics might not be 100 percent accurate.

17.8 Oracle Text on Oracle Real Application Clusters

For maximum throughput and performance for OLAP applications, you can parallelize Oracle Text queries across Oracle Real Application Clusters (Oracle RAC) nodes. You can manage Oracle Text indexes on Oracle RAC nodes with Text Manager in Oracle Enterprise Manager, as described in "Text Manager in Oracle Enterprise Manager".

17 Administering Oracle Text

17.1 Oracle Text Users and Roles

17.1.1 CTXSYS User

17.1.2 CTXAPP Role

17.1.3 Granting Roles and Privileges to Users

17.2 DML Queue

17.3 CTX_OUTPUT Package

17.4 CTX_REPORT Package

17.5 Text Manager in Oracle Enterprise Manager

17.5.1 Using Text Manager

17.5.2 Viewing General Information for an Oracle Text Index

17.5.3 Checking Oracle Text Index Health

17.6 Servers and Indexing

17.7 Tracking Database Feature Usage in Oracle Enterprise Manager

17.8 Oracle Text on Oracle Real Application Clusters

17.9 Unsupported Oracle Text Operations in Oracle Database Vault Realm