Oracle | DBMS_MAX_STRING

Oracle DBMS_MAX_STRING_SIZE Version 26ai

General Information

Library Note

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Oracle Database 26ai will be available on generic Linux platforms in January and soon on AIX and Windows

Purpose Assumed to allow dynamically resetting the database maximum string size: To be validated.

AUTHID DEFINER

Data Types

These types are independent objects owned by SYS: They are not defined inside the package (see Dependencies, below). /* Record type returned by CHECK_MAX_STRING_SIZE API */ CREATE OR REPLACE TYPE dbms_max_string_size_rec force as object( type VARCHAR2(128), object_owner dbms_id, object_name dbms_id, column_name dbms_id, reason VARCHAR2(4000)) NOT PERSISTABLE; / /* Table type returned by CHECK_MAX_STRING_SIZE API */ CREATE OR REPLACE TYPE dbms_max_string_size_tbl FORCE AS TABLE OF (dbms_max_string_size_rec) NOT PERSISTABLE; /

Dependencies

DBA_REGISTRY	DBMS_MAX_STRING_SIZE_TBL	PLITBLM
DBA_TAB_COLS	DBMS_SCHEDULER	PROPS$
DBA_VIEWS	DBMS_SQL	V$PARAMETER
DBMS_ASSERT	DBMS_STANDARD	V$PDBS
DBMS_MAX_STRING_SIZE_REC

Documented No

Exceptions

Error Code	Reason
ORA-2000	An object exists that will prevent the string size modification

First Available 20c

Security Model Owned by SYS with EXECUTE granted to the EXECUTE_CATALOG_ROLE role.

Source {ORACLE_HOME}/rdbms/admin/dbmsmss.sql
{ORACLE_HOME}/rdbms/admin/prvtmss.plb

Subprograms

CHECK_MAX_STRING_SIZE

MODIFY_MAX_STRING_SIZE

MODIFY_MAX_STRING_SIZE_POST

CHECK_MAX_STRING_SIZE

Determines if the MAX_STRING_SIZE can be changed to the "new" value

Only supported value is "STANDARD" and dbms_max_string_size.check_max_string_size(newValue IN VARCHAR2) RETURN dbms_max_string_size_tbl;

SELECT object_owner AS obj_own, object_name

      FROM TABLE (dbms_max_string_size.check_max_string_size('STANDARD');

      

      OBJ_OWN OBJECT_NAME        COLUMN_NAME                    REASON

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

      VECSYS  VECTOR$INDEX       SYS_IME_OSON_1D9C844870E84F37B Physical column exceeds STANDARD length FB3BE75CB1B97FC limit

      

      VECSYS VECTOR$INDEX        SYS_IME_OSON_745AACB0ECA34F2EB Physical column exceeds STANDARD length FB0EA98DBCD16C6 limit

      

      VECSYS VECTOR$INDEX        SYS_IME_OSON_F0E868E34F6A4F16B Physical column exceeds STANDARD length F670BA95373CAF9 limit

      

      VECSYS VECTOR$INDEX$BUILD$ SYS_IME_OSON_9AA39E2EC9EC4FE1B Physical column exceeds STANDARD length FCC2AE8266D39FD limit

MODIFY_MAX_STRING_SIZE

Updates MAX_STRING_SIZE to the "new" value

23ai bug file in 20c and refiled in
BugDB on Feb 1, 2023. dbms_max_string_size.modify_max_string_size(newValue IN VARCHAR2);

exec dbms_max_string_size.modify_max_string_size('STANDARD');

           *

      ORA-01422: exact fetch returns more than requested number of rows

MODIFY_MAX_STRING_SIZE_POST

Post-processing set for modify_max_string_size dbms_max_string_size.modify_max_string_size_post(newValue IN VARCHAR2);

exec dbms_max_string_size.modify_max_string_size_post('STANDARD');

      

      PL/SQL procedure successfully completed.