Oracle | DBMS_HCS

Oracle DBMS_HCS_LOG Version 26ai

General Information

Library Note

Morgan's Library Page Header

The best Oracle News for FY2026

Oracle Database 26ai is now availble. If you haven't you downloaded already: Why?

Purpose Utility functions for HCS Logging from PL/SQL code

AUTHID CURRENT_USER

Constants

Name	Data Type	Value
Logging
HCSLOG_VRB_NONE	INT	0
HCSLOG_VRB_SUMMARY	INT	1
HCSLOG_VRB_DETAIL_ALLOCS	INT	2
HCSLOG_VRB_DETAIL	INt	3

Dependencies

DBMS_ASSERT	DBMS_HIERARCHY	PLITBLM
DBMS_AVTUNE_UTIL	DBMS_MX_ODBO	UTL_FILE
DBMS_HCS_LIB	DBMS_STANDARD

Documented No

Exceptions

Error Code	Reason
ORA-20000	Log called before Log START
ORA-44003	INVALID_SQL_NAME

First Available 21c

Security Model Owned by SYS with EXECUTE granted to the DBA, PDB_DBA and AVTUNE_PKG_ROLE roles

Source {ORACLE_HOME}/rdbms/admin/dbmshcslog.sql

Subprograms

CLEAR_LOGS	HCS_CALL_CTX_CLEAR_CLOB	HCS_CALL_CTX_LOG_END
CREATE_VIEWS	HCS_CALL_CTX_GET_LOG_VRB	HCS_CALL_CTX_LOG_START
DROP_VIEWS	HCS_CALL_CTX_LOG	PURGE
HCS_CALL_CTX_BUILD_CLOB	HCS_CALL_CTX_LOG_CLEAR_CLOB	SET_LOGGING_LEVEL

CLEAR_LOGS

Clear the instance's logs dbms_hcs_log.clear_logs;

exec dbms_hcs_log.clear_logs;

      

      PL/SQL procedure successfully completed.

CREATE_VIEWS

Creates objects and views used for logging dbms_hcs_log.create_views( user IN VARCHAR2 DEFAULT SYS_CONTEXT('USERENV', 'CURRENT_SCHEMA'));

exec dbms_hcs_log.create_views;

      

      PL/SQL procedure successfully completed.

      

      SELECT object_name

      FROM dba_objects

      WHERE object_type = 'VIEW'

      and owner = USER

      AND last_ddl_time > SYSDATE-1/24

      ORDER BY 1;

      

      OBJECT_NAME

      --------------------------------

      TKHCS_LOG_BASE_VIEW

      TKHCS_LOG_CALLS

      TKHCS_LOG_CURRSESS_LASTLOG_VIEW

      TKHCS_LOG_CURRSESS_VIEW

      TKHCS_LOG_LASTSESS_VIEW

      TKHCS_LOG_VIEW

DROP_VIEWS

Drops objects and views used for logging dbms_hcs_log.drop_views( user IN VARCHAR2 DEFAULT SYS_CONTEXT('USERENV', 'CURRENT_SCHEMA'));

exec dbms_hcs_log.drop_views;

HCS_CALL_CTX_BUILD_CLOB

Builds a package private clob over numerous functions used for building a CLOB to log in one call dbms_hcs_log.hcs_call_ctx_build_clob(line IN VARCHAR2);

exec dbms_hcs_log.hcs_call_ctx_build_clob('TEST');

      

      PL/SQL procedure successfully completed.

HCS_CALL_CTX_CLEAR_CLOB

Clears the private CLOB dbms_hcs_log.hcs_call_ctx_clear_clob;

exec dbms_hcs_log.hcs_call_ctx_clear_clob;

      

      PL/SQL procedure successfully completed.

HCS_CALL_CTX_GET_LOG_VRB

Returns the logging detail level (0 - 3) dbms_hcs_log.hcs_call_ctx_get_log_vrb RETURN NUMBER;

SELECT dbms_hcs_log.hcs_call_ctx_get_log_vrb;

      

      HCS_CALL_CTX_GET_LOG_VRB

      ------------------------

                             1

HCS_CALL_CTX_LOG

Sets CALL context for subsequent call_ctx_log dbms_hcs_log.hcs_call_ctx_log(callStr IN VARCHAR2);

TBD

HCS_CALL_CTX_LOG_CLEAR_CLOB

writes the CLOB to the log and reinitializes it dbms_hcs_log.hcs_call_ctx_log_clear_clob(p_comp IN VARCHAR2);

exec dbms_hcs_log.hcs_call_ctx_log_clear_clob('TEST');

          
      *

      ORA-20000: Log called before Log START

      

      See HCS_CALL_CTX_LOG_START Demo Below

HCS_CALL_CTX_LOG_END

Logs END call and nulls out current call context dbms_hcs_log.hcs_call_ctx_log_end;

See HCS_CALL_CTX_LOG_START Demo Below

HCS_CALL_CTX_LOG_START

Sets the CALL context for subsequent call_ctx_log dbms_hcs_log.hcs_call_ctx_log_start(callStr IN VARCHAR2);

exec dbms_hcs_log.hcs_call_ctx_log_start('TEST');

      

      PL/SQL procedure successfully completed.

      

      exec dbms_hcs_log.hcs_call_ctx_log_clear_clob('TEST');

      

      PL/SQL procedure successfully completed.

      

      exec dbms_hcs_log.hcs_call_ctx_log_end;

      

      PL/SQL procedure successfully completed.

PURGE

Purges HCS logs to the given max_segments. If call_only is TRUE (default) then the value for max_segments is not used for subsequent logging. If call_only is FALSE, the value is used for subsequent logging. dbms_hcs_log.purge( max_segments IN NUMBER, call_only IN BOOLEAN DEFAULT TRUE);

exec dbms_hcs_log.purge(1, TRUE);

      

      PL/SQL procedure successfully completed.

SET_LOGGING_LEVEL (new 23ai)

Sets the analytic view log verbosity detail level dbms_hcs_log.set_logging_level( logging_level IN INT DEFAULT NULL, alter_session IN BOOLEAN DEFAULT TRUE);

exec dbms_hcs_log.set_logging_level(1, TRUE);

      

      PL/SQL procedure successfully completed.