ORACLE 12C Same Columns Create multiple indexing methods

Starting with Oracle 12C allows different types of index to be created on the same column for performance tuning, with different types of index mainly including (B*tree vs bitmap,local vs Global)
ORACLE 11G

The code is as follows

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Sql> select * from V$version; BANNER -------------------------------------------------------------------------------- Oracle Database 11g Enterprise Edition release 11.2.0.3.0-production Pl/sql Release 11.2.0.3.0-production CORE 11.2.0.3.0 Production TNS for Linux:version 11.2.0.3.0-production Nlsrtl Version 11.2.0.3.0-production sql> CREATE TABLE T_xifenfei 2 ( 3 EMPNO Number (9) PRIMARY KEY, 4 EmpName VARCHAR2 () not NULL, 5) 6/ Table created. Sql> CREATE INDEX emp_dept_btree_idx on EMP (DEPTNO); Index created. sql> CREATE BITMAP INDEX emp_deptno_bitmap_idx on EMP (DEPTNO) invisible; CREATE BITMAP INDEX emp_deptno_bitmap_idx on EMP (DEPTNO) invisible * ERROR at line 1: Ora-01408:such column list already indexed ORACLE 12C Cdb_pdb@chf> select * from V$version; BANNER con_id -------------------------------------------------------------------------------- ---------- Oracle Database 12c Enterprise Edition release 12.1.0.1.0-64bit Production 0 Pl/sql Release 12.1.0.1.0-production 0 CORE 12.1.0.1.0 Production 0 TNS for 64-bit windows:version 12.1.0.1.0-production 0 Nlsrtl Version 12.1.0.1.0-production 0 cdb_pdb@chf> CREATE TABLE T_xifenfei 2 ( 3 EMPNO Number (9) PRIMARY KEY, 4 EmpName VARCHAR2 (not NULL) 5) 6/

Table has been created.

The code is as follows	Copy Code
Cdb_pdb@chf> CREATE INDEX emp_dept_btree_idx on EMP (DEPTNO);

The index has been created.

The code is as follows	Copy Code
cdb_pdb@chf> CREATE BITMAP INDEX emp_deptno_bitmap_idx on EMP (DEPTNO); CREATE BITMAP INDEX emp_deptno_bitmap_idx on EMP (DEPTNO)

*

Line 1th Error:

ORA-01408: This column list is indexed

cdb_pdb@chf> CREATE BITMAP INDEX emp_deptno_bitmap_idx on EMP (DEPTNO) invisible;

The index has been created.