MSCD640/MCT615
Lab 2
Name: _________________________________________
Date: __________________________________________
----------------------------------------------------------------------------------The purpose of this lab is to become familiar with the following types of basic DBA
tasks:
 Managing users and basic security
 Creating and managing tables and constraints
 Creating and managing indexes
 Creating and managing views, synonyms, and sequences
Read Chapters 6 through 9 in the book before starting this lab.
These labs focus on how to perform DBA tasks from the SQL*Plus command prompt.
These labs do not show how to perform tasks from Enterprise Manager. I prefer that
students learn basic DBA tasks from SQL*Plus for the following reasons:
 Not all environments have Enterprise Manager installed, therefore you’ll need to
know how to perform basic DBA tasks from the SQL command prompt.
 Performing the tasks manually from SQL gives you a better understanding of the
underlying SQL used to accomplish DBA tasks.
 If you can perform DBA tasks from SQL, then you’ll have no problems
understanding how to perform the same tasks in Enterprise Manager.
To get an “A” grade on this lab:
 Answer all questions.
 Provide output of steps that require you to perform a task. The output can be a
spool file, cut and paste from the screen to a word document, screen shots. I need
to see something to verify that you ran the labs. I’m expecting you to turn in a
word document that contains each question and also the corresponding answers to
questions asked and output from SQL statements.
----------------------------------------------------------------------------------Lab 2, Part 1: Users and Basic Security
Read Chapter 6 in the book.
----------------------------------------------------------------------------------1. Startup your database, from the operating system prompt:
sqlplus / as sysdba
SQL> show user;
SQL> startup;
SQL> select name from v$database;
----------------------------------------------------------------------------------2. What users exist in your database?
11g book: page 112
12c book: page 127
SQL> select username,lock_date,expiry_date, created from dba_users order by 1;
What’s the difference between the LOCK_DATE and EXPIRY_DATE?
----------------------------------------------------------------------------------3. Lock all of the users in your database except for SYS. To perform this task, use SQL
that generates SQL.
11g book: page 112
12c book: page 128
select
'alter user ' || username || ' password expire account lock;'
from dba_users
where username not in ('SYS');
Run the SQL statements that are generated by the prior SQL to actually lock the
accounts.
Verify that the accounts are locked:
SQL> select username, lock_date, expiry_date, created from dba_users order by 1;
----------------------------------------------------------------------------------4. Unlock the SYSTEM account.
11g book: page 112
12c book: page 140
SQL> alter user system account unlock;
----------------------------------------------------------------------------------5. Are there any accounts in your database that aren’t the default accounts? Run this
script while connected to the SYS user.
11g book: page 113
12c book: page 130
select
distinct u.username
,case when d.user_name is null then 'DBA created account'
else 'Oracle created account'
end
from dba_users u
,default_pwd$ d
where u.username=d.user_name(+)
order by 1;
----------------------------------------------------------------------------------6. Which accounts in your database have never had the password changed? Run this
script while connected to the SYS user.
11g book: page 113
12c book: page 144
select
name
,to_char(ctime,'dd-mon-yy hh24:mi:ss')
,to_char(ptime,'dd-mon-yy hh24:mi:ss')
,length(password)
from user$
where password is not null
and password not in ('GLOBAL','EXTERNAL')
and ctime=ptime;
----------------------------------------------------------------------------------7. What are the differences between the SYS and SYSTEM users in an Oracle database?
11g book: page 114
12c book: page 128
----------------------------------------------------------------------------------8. Alter the password for the SYSTEM user to a password of your choice:
SQL> alter user system identified by <input a password here>’;
For example:
SQL> alter user system identified by foo;
----------------------------------------------------------------------------------9. Connect to the SYSTEM account with the password that you established in the prior
step:
SQL> connect system/<input password>
For example:
SQL> connect system/foo
SQL> show user;
----------------------------------------------------------------------------------10. Check on the default and permanent tablespaces for users in your database:
set linesize 132
-select
username
,default_tablespace
,temporary_tablespace
from dba_users;
For any users in your database, would you recommend changing what the current default
and temporary tablespace are?
----------------------------------------------------------------------------------11. Create a user in your database. Run this script while connected to the SYSTEM
account.
11g book: page 115
12c book: page 133
create user heera identified by chaya
default tablespace users
temporary tablespace temp;
----------------------------------------------------------------------------------12. Attempt to connect to the user you just created:
SQL> connect heera/chaya
What happens?
----------------------------------------------------------------------------------13. Connect as SYSTEM and grant the appropriate privileges required to allow a user to
connect to the database:
SQL> conn system/<password>
SQL> grant create session to heera;
Now try to connect as HEERA:
SQL> connect heera/chaya
What happens?
Which user are you connect as to your database?
SQL> show user;
----------------------------------------------------------------------------------14. Connect to SYSTEM and alter the password of the HEERA account:
SQL> conn system/<password>
SQL> alter user heera identified by foobar;
----------------------------------------------------------------------------------15. As SYS, create a secure password function.
11g book: pages 119-120
12c book: page 144
SQL> conn / as sysdba
SQL> show user;
SQL> @?/rdbms/admin/utlpwdmg
----------------------------------------------------------------------------------16. Does the default profile for your database have a password verify function assigned to
it?
SQL> set lines 132
SQL> select * from dba_profiles where profile = 'DEFAULT';
----------------------------------------------------------------------------------17. Alter the default profile for your database to use the password function:
11g database (page 119):
SQL> alter profile default limit PASSWORD_VERIFY_FUNCTION
verify_function_11G;
Verify:
SQL> select * from dba_profiles where profile = 'DEFAULT';
12c database (page 145):
SQL> alter profile default limit PASSWORD_VERIFY_FUNCTION
ora12c_verify_function;
Verify:
SQL> select * from dba_profiles where profile = 'DEFAULT';
----------------------------------------------------------------------------------18. Attempt to alter the HEERA user’s password:
SQL> alter user heera identified by foo;
What happened?
----------------------------------------------------------------------------------19. Set the password verify function for the default profile for your database to null:
SQL> alter profile default limit PASSWORD_VERIFY_FUNCTION null;
----------------------------------------------------------------------------------20. Now can you modify the HEERA user’s password to something not entirely secure:
SQL> alter user heera identified by foo;
----------------------------------------------------------------------------------21. Lock and drop the HEERA account:
SQL> alter user heera account lock;
SQL> drop user heera cascade;
What is the purpose of locking an account before it is dropped?
----------------------------------------------------------------------------------22. What is the purpose of a database profile?
11g book: page 123
12c book: page 141
----------------------------------------------------------------------------------23. What is the purpose of a SQL profile?
11g book: (not covered in the class book)
12c book: (page 141)
----------------------------------------------------------------------------------24. Create a somewhat secure database profile.
11g book: pages 125-126
12c book: page 143
11g example:
CREATE PROFILE SECURE_APP
LIMIT
PASSWORD_LIFE_TIME 200
PASSWORD_GRACE_TIME 10
PASSWORD_REUSE_TIME 1
PASSWORD_REUSE_MAX 1
FAILED_LOGIN_ATTEMPTS 3
PASSWORD_LOCK_TIME 1
PASSWORD_VERIFY_FUNCTION verify_function_11G;
12c example:
CREATE PROFILE SECURE_APP
LIMIT
PASSWORD_LIFE_TIME 200
PASSWORD_GRACE_TIME 10
PASSWORD_REUSE_TIME 1
PASSWORD_REUSE_MAX 1
FAILED_LOGIN_ATTEMPTS 3
PASSWORD_LOCK_TIME 1
PASSWORD_VERIFY_FUNCTION ora12c_verify_function;
----------------------------------------------------------------------------------25. Connect as SYSTEM. Create a user named APP_USER and grant the user
CONNECT:
SQL> conn system/<password>
SQL> create user app_user identified by foo ;
SQL> grant create session to app_user;
----------------------------------------------------------------------------------26. Assign the SECURE_APP profile to APP_USER:
SQL> alter user app_user profile secure_app;
----------------------------------------------------------------------------------27. Attempt to change the APP_USER password:
SQL> alter user app_user identified by foofoo;
What happens?
Try a more secure password:
SQL> alter user app_user identified by f00f00f00;
----------------------------------------------------------------------------------28. Enable your database to be able to constrain resources via a profile:
SQL> show parameter resource_limit;
If it’s not TRUE, then set it:
SQL> alter system set resource_limit=true scope=both;
----------------------------------------------------------------------------------29. As SYSTEM, create a profile that limits system resource usage.
11g book: pages 127-128
12c book: page 146
create profile user_profile_limit
limit
sessions_per_user 20
cpu_per_session 240000
logical_reads_per_session 1000000
connect_time 480
idle_time 2;
----------------------------------------------------------------------------------30. Assign the profile to APP_USER:
SQL> alter user app_user profile user_profile_limit;
Verify:
SQL> select username, profile from dba_users where profile like 'USER%';
----------------------------------------------------------------------------------31. Connect as APP_USER:
SQL> conn app_user/f00f00f00
Don’t type anything in for a few minutes. What happens after a few minutes of idle time?
Try to run a SQL statement:
SQL> select * from user_users;
What happens?
----------------------------------------------------------------------------------32. Connect as SYSTEM, and modify the USER_PROFILE_LIMIT profile:
SQL> conn system/<password>
SQL> alter profile user_profile_limit limit idle_time 10;
----------------------------------------------------------------------------------33. Connect as APP_USER and attempt to create a table:
SQL> conn app_user/f00f00f00
SQL> show user;
SQL> create table emp(emp_id number);
----------------------------------------------------------------------------------34. Connect as SYSTEM, and grant some basic privileges to APP_USER:
SQL> connect system/<password>
SQL> grant create table to app_user;
SQL> alter user app_user quota unlimited on users;
----------------------------------------------------------------------------------35. Connect as APP_USER and attempt to create a table:
SQL> conn app_user/f00f00f00
SQL> show user;
SQL> create table emp(emp_id number);
SQL> describe emp;
SQL> insert into emp values(1);
----------------------------------------------------------------------------------36. Connect as SYSTEM and create a new user named APP_MGMT:
SQL> conn system/<password>
SQL> create user app_mgmt identified by foo;
SQL> grant connect to app_mgmt;
SQL> grant create synonym to app_mgmt;
SQL> alter user app_mgmt quota unlimited on users;
----------------------------------------------------------------------------------37. Connect as APP_USER and grant object privileges on the table EMP to
APP_MGMT:
SQL> conn app_user/f00f00f00
SQL> grant insert, update, delete, select on emp to app_mgmt;
-----------------------------------------------------------------------------------
38. Connect as APP_MGMT, and see if you can perform DML operations on the insert
into app_user.emp values(1);APP_USER.EMP table:
SQL> conn app_mgmt/foo
SQL> insert into app_user.emp values(2);
SQL> commit;
SQL> select * from app_user.emp;
Why do you have to place the schema name (of app_user) before the table name?
----------------------------------------------------------------------------------39. As APP_MGMT, create a synonym:
SQL> select * from emp;
What happens?
SQL> create synonym emp for app_user.emp;
SQL> select * from emp;
Why don’t you have to place the schema name in front of the table name anymore?
----------------------------------------------------------------------------------39. Connect as SYSTEM and create a role:
SQL> connect system/<password>
SQL> create role app_read;
SQL> grant select on app_user.emp to app_read;
Now create a user and assign basic privileges and access to the role:
SQL> create user app_select identified by foo;
SQL> grant create session to app_select;
SQL> grant app_read to app_select;
----------------------------------------------------------------------------------40. Connect as app_select and see if it has access to the underlying table:
SQL> conn app_select/foo
SQL> select * from app_user.emp;
-----------------------------------------------------------------------------------
----------------------------------------------------------------------------------Lab 2, Part 2: Tables and Constraints
Read Chapter 7 in the book.
----------------------------------------------------------------------------------40. As SYSTEM, create a user and grant it appropriate privileges.
SQL> conn system/<password>
SQL> create user inv_user identified by inv_user_pwd;
SQL> grant create session to inv_user;
SQL> grant create table to inv_user;
SQL> alter user inv_user quota unlimited on users;
----------------------------------------------------------------------------------41. Connect as INV_USER and create a heap-organized table that contains number,
varchar, date, and timestamp type columns.
11g book: page 135
12c book: page 161
SQL> conn inv_user/inv_user_pwd
create table d_sources(
d_source_id number not null,
source_type varchar2(32),
create_dtt date default sysdate not null,
update_dtt timestamp(5)
);
----------------------------------------------------------------------------------42. Does the table contain any segments and extents?
SQL> select count(*) from user_segments where segment_name = 'D_SOURCES';
SQL> select count(*) from user_extents where segment_name = 'D_SOURCES';
----------------------------------------------------------------------------------43. Insert a row into the D_SOURCES table. Verify that the data dictionary now contains
information regarding segments and extents for the table.
11g book: pages 141-142
12c book: pages 167-168
SQL> insert into d_sources (d_source_id, source_type) values(1, 'HQ');
SQL> select count(*) from user_segments where segment_name = 'D_SOURCES';
SQL> select count(*) from user_extents where segment_name = 'D_SOURCES';
What is Oracle’s deferred segment creation feature?
----------------------------------------------------------------------------------44. As INV_USER, create two tables that are related by a foreign key constraint.
11g book: pages 136-138
12c book: page 198
create table operating_systems(
operating_system_id number(19, 0) not null,
version
varchar2(50),
os_name
varchar2(256),
release
varchar2(50),
vendor
varchar2(50),
create_dtt
date
default sysdate not null,
update_dtt
date,
constraint operating_systems_pk primary key (operating_system_id)
using index tablespace users
)
tablespace users
;
-create unique index operating_system_uk1 on operating_systems
(os_name, version, release, vendor)
tablespace users
;
-create table computer_systems(
computer_system_id number(38, 0) not null,
agent_uuid
varchar2(256),
operating_system_id number(19, 0) not null,
hardware_model
varchar2(50),
create_dtt
date default sysdate not null,
update_dtt
date,
constraint computer_systems_pk primary key (computer_system_id)
using index tablespace users
) tablespace users;
-comment on column computer_systems.computer_system_id is
'Surrogate key generated via an Oracle sequence.';
-create unique index computer_system_uk1 on computer_systems(agent_uuid)
tablespace users;
-alter table computer_systems add constraint computer_systems_fk1
foreign key (operating_system_id)
references operating_systems(operating_system_id);
----------------------------------------------------------------------------------45. As INV_USER, verify that tables, indexes, constraints, and comments were created:
SQL> select table_name, status from user_tables;
SQL> select index_name, status, index_type from user_indexes;
SQL> select constraint_name, constraint_type, table_name from user_constraints;
SQL> select table_name, column_name, comments from user_col_comments where
comments is not null;
----------------------------------------------------------------------------------46. As INV_USER, create a table with a virtual column.
11g book: pages 138-140
12c book: page 164
create table inv(
inv_id number
,inv_count number
,inv_status generated always as (
case when inv_count <= 100 then 'GETTING LOW'
when inv_count > 100 then 'OKAY'
end)
);
Verify:
SQL> set long 10000;
SQL> select dbms_metadata.get_ddl('TABLE','INV') from dual;
----------------------------------------------------------------------------------47. Insert data into INV, and verify that the virtual column works as expected:
SQL> insert into inv (inv_id, inv_count) values (1,100);
SQL> select * from inv;
What are the main advantages to using virtual columns?
----------------------------------------------------------------------------------48. Make the INV table read only.
11g book: pages 140-141
12c book: page 167
SQL> alter table inv read only;
Verify:
SQL> select table_name, read_only from user_tables where read_only='YES';
Try to insert some data:
SQL> insert into inv (inv_id, inv_count) values (2,200);
----------------------------------------------------------------------------------49. Drop and re-create table INV. Use the compression feature.
11g book: pages 143-144
12c book: page 172
SQL> drop table inv purge;
create table inv(
inv_id number
,inv_name varchar2(64)
) compress for oltp;
Verify:
select
table_name
,compression
,compress_for
from user_tables where table_name='INV';
----------------------------------------------------------------------------------50. Drop and re-create a table with NOLOGGING enabled.
11g book: pages 144-145
12c book: page 174
SQL> drop table inv purge;
create table inv(inv_id number)
tablespace users
nologging;
Insert some data using a direct path feature (such as an append hint):
SQL> insert /*+ append_values */ into inv values(1);
SQL> select * from inv;
What happened?
SQL> commit;
SQL> select * from inv;
What are the advantages to using nologging combined with a direct path loading
operation?
----------------------------------------------------------------------------------51. Create a table using the CTAS approach.
11g book: page 146
12c book: page 176
SQL> create table test_users as select * from all_users;
SQL> desc test_users
SQL> select count(*) from test_users;
----------------------------------------------------------------------------------52. Explain under what circumstances a DBA would use DDL_LOCK_TIMEOUT?
11g book: page 147
12c book: page 178
----------------------------------------------------------------------------------53. Rename the INV table to INV_OLD.
11g book: page 147
12c book: page 179
SQL> rename inv to inv_old;
Why would you want to rename a table?
Rename INV_OLD to INV:
SQL> rename inv_old to inv;
----------------------------------------------------------------------------------54. Add a columns to INV.
11g book: pages 147-148
12c book: page 179
SQL> alter table inv add(inv_count number);
SQL> alter table inv add(inv_desc varchar2(10));
Verify:
SQL> desc inv;
-----------------------------------------------------------------------------------
55. Alter a column.
11g book: pages 148-149
12c book: page 179
SQL> alter table inv modify inv_desc varchar2(256);
Verify:
SQL> desc inv;
----------------------------------------------------------------------------------56. Rename a column.
11g book: page 149
12c book: page 181
SQL> alter table inv rename column inv_count to inv_amt;
Verify:
SQL> desc inv;
----------------------------------------------------------------------------------57. Drop a column.
11g book: pages 149-150
12c book: page 181
SQL> alter table inv drop (inv_desc);
Verify:
SQL> desc inv;
----------------------------------------------------------------------------------58. Drop the INV table without purging it.
11g book: pages 151-153
12c book: page 183
SQL> drop table inv;
Is it in the recyclebin?
SQL> show recyclebin;
----------------------------------------------------------------------------------59. Undrop INV.
11g book: pages 151-153
12c book: page 184
SQL> flashback table inv to before drop;
Verify:
SQL> desc inv;
Why would you ever want to undrop a table?
-----------------------------------------------------------------------------------
----------------------------------------------------------------------------------Lab 2, Part 3: Indexes
Read Chapter 8 in the book.
----------------------------------------------------------------------------------60. Connect as INV_USER (if you’re not already connected as INV_USER):
SQL> conn inv_user/inv_user_pwd
----------------------------------------------------------------------------------61. Verify that the d_sources table is still valid:
SQL> desc d_sources;
----------------------------------------------------------------------------------62. Create an index.
11g book: pages 175-176.
12c book: page 210
SQL> create index d_sources_idx1 on d_sources(d_source_id);
Verify:
select index_name, index_type, table_name, tablespace_name
from user_indexes
where table_name = 'D_SOURCES';
----------------------------------------------------------------------------------63. Drop the index:
SQL> drop index d_sources_idx1;
----------------------------------------------------------------------------------64. Drop the INV table and re-create it.
SQL> drop table inv purge;
create table inv(
inv_name varchar2(30)
,cust_name varchar2(30));
Verify:
SQL> desc inv;
----------------------------------------------------------------------------------65. Create a concatenated index.
11g book: pages 176-177
12c book: page 217
SQL> create index inv_idx3 on inv(inv_name, cust_name);
Verify:
select index_name, column_name, column_position
from user_ind_columns
where index_name = 'INV_IDX3';
What is the advantage of creating a concatenated index?
----------------------------------------------------------------------------------66. Create a table named emp:
SQL> create table emp(emp_id number, emp_name varchar2(30));
----------------------------------------------------------------------------------67. Create a function based index.
11g book: page 177
12c book: page 218
SQL> create index user_upper_idx on emp(upper(emp_name));
Verify:
SQL> SET LONG 500
SQL> select index_name, column_expression from user_ind_expressions;
----------------------------------------------------------------------------------68. Add a column to the INV table:
SQL> alter table inv add(sku_id number);
Verify:
SQL> desc inv;
----------------------------------------------------------------------------------69. Create a unique index on INV.SKU_ID.
11g book: pages 178-179
12c book: page 219
SQL> create unique index inv_uidx1 on inv(sku_id);
Verify:
SQL> insert into inv(sku_id) values (1);
SQL> insert into inv(sku_id) values (1);
Verify via the data dictionary:
SQL> select index_name, uniqueness from user_indexes;
----------------------------------------------------------------------------------70. Create a reverse-key index.
11g book: pages 181-182
12c book: page 222
SQL> alter table inv add(inv_id number);
Verify:
SQL> desc inv;
SQL> create index inv_idx1 on inv(inv_id) reverse;
Verify:
SQL> select index_name, index_type from user_indexes;
What is the main advantage of a reverse-key index?
----------------------------------------------------------------------------------71. Create a table and a key compressed index.
11g book: page 182
12c book: page 223
create table users(
last_name varchar2(30)
,first_name varchar2(30)
,address_id number);
SQL> create index users_idx1 on users(last_name, first_name) compress 2;
Verify:
select
index_name
,compression
from
user_indexes
where index_name like 'USERS%';
What is the advantage of compression?
----------------------------------------------------------------------------------72. Make an existing index an invisible index.
11g book: pages 183-185
12c book: page 224
SQL> select index_name, status, visibility from user_indexes;
SQL> alter index inv_idx1 invisible;
SQL> select index_name, status, visibility from user_indexes;
Why would you ever want to use an invisible index?
----------------------------------------------------------------------------------73. Display the code to recreate in index.
11g book: page 188
12c book: page 227
SQL> set long 10000
SQL> select dbms_metadata.get_ddl('INDEX','INV_IDX1') from dual;
----------------------------------------------------------------------------------74. Rebuild an index using parallel and nologging.
11g book: pages 188-189
12c book: page 228
SQL> alter index inv_idx1 rebuild parallel nologging;
DBAs often debate the merits of rebuilding an index. What are some valid reasons for
rebuilding an index?
-----------------------------------------------------------------------------------
----------------------------------------------------------------------------------Lab 2, Part 4: Views, Synonyms, and Sequences
Read Chapter 9 in the book.
----------------------------------------------------------------------------------75. Ensure that the CREATE VIEW system privilege, CREATE SYNONYM, and
CREATE SEQUENCE system privilege has been granted to INV_USER.
As SYSTEM:
SQL> conn system/<password>
SQL> grant create view to inv_user;
SQL> grant create synonym to inv_user;
SQL> grant create sequence to inv_user;
----------------------------------------------------------------------------------76. Connect as INV_USER and create a table.
11g book: pages 193-194
12c book: page 238
SQL> conn inv_user/inv_user_pwd
create table sales(
sales_id number primary key
,amnt number
,state varchar2(2)
);
Verify:
SQL> desc sales;
----------------------------------------------------------------------------------77. Create a view.
11g book: page 194
12c book: page 238
create or replace view sales_rockies as
select
sales_id
,amnt
,state
from sales
where state in ('GALWAY','CO','UT','WY','ID','AZ');
Verify:
SQL> desc sales_rockies;
----------------------------------------------------------------------------------78. Experiment with inserting into the table versus the view:
SQL> insert into sales values(1,500,'CO');
SQL> insert into sales values(2,500,'CA');
SQL> commit;
SQL> select * from sales;
SQL> select * from sales_rockies;
What are the advantages to using view?
----------------------------------------------------------------------------------79. Is it possible to insert into a view?
insert into sales_rockies(
sales_id, amnt, state)
values
(3,300,'CO');
SQL> select * from sales_rockies;
When you insert into a view, where is the underlying data actually stored? (in what
database object?)
----------------------------------------------------------------------------------80. Recreate the view with the WITH CHECK OPTION.
11g book: pages 194-195
12c book: pages 239-240
create or replace view sales_rockies as
select
sales_id
,amnt
,state
from sales
where state in ('CORK','CO','UT','WY','ID','AZ')
with check option;
Run the following two update statements:
SQL> update sales_rockies set state='ID' where sales_id=1;
SQL> update sales_rockies set state='CA' where sales_id=1;
Why did the first update work but not the second one?
----------------------------------------------------------------------------------81. Recreate the view as READ ONLY.
11g book: page 195
12c book: page 240
create or replace view sales_rockies as
select
sales_id
,amnt
,state
from sales
where state in ('KERRY','CO','UT','WY','ID','AZ')
with read only;
Now try to update it:
SQL> update sales_rockies set state='ID' where sales_id=1;
Why did it fail?
----------------------------------------------------------------------------------82. Generate the DDL required to recreate the view.
11g book: pages 198-199
12c book: page 245
SQL> set long 5000
SQL> select dbms_metadata.get_ddl('VIEW','SALES_ROCKIES','INV_USER') from
dual;
----------------------------------------------------------------------------------83. Create a synonym for the sales_rockies view.
11g book: pages 200-201
12c book: page 248
SQL> create synonym sr_view for sales_rockies;
Verify:
SQL> desc sr_view
----------------------------------------------------------------------------------84. What is the difference between a private synonym and a public synonym?
11g book: pages 201-202
12c book: page 248
----------------------------------------------------------------------------------85. Display synonym information contained in the data dictionary.
11g book: pages 202-203
12c book: page 250
select
synonym_name, table_owner, table_name, db_link
from user_synonyms
order by 1;
----------------------------------------------------------------------------------86. Create a sequence using the defaults.
11g book: pages 204-206
12c book: page 251
SQL> create sequence inv_seq;
----------------------------------------------------------------------------------87. Create a sequence but specify some non-default values.
11g book: pages 204-206
12c book: page 251
SQL> create sequence inv2_seq start with 10000 maxvalue 1000000;
----------------------------------------------------------------------------------88. Use sequence pseudo column values.
11g book: pages 204-206
12c book: page 252
SQL> select inv_seq.nextval from dual;
SQL> select inv_seq.currval from dual;
----------------------------------------------------------------------------------89. Verify the structure of the INV table:
SQL> desc inv;
Use a sequence to populate a column when inserting:
insert into inv (inv_id) values (inv_seq.nextval);
insert into inv (inv_id) values (inv_seq.nextval);
insert into inv (inv_id) values (inv_seq.nextval);
Verify:
SQL> select * from inv;
----------------------------------------------------------------------------------90. Display the sequence metadata.
11g book: pages 208-209
12c book: page 255
SQL> select dbms_metadata.get_ddl('SEQUENCE','INV_SEQ') from dual;
----------------------------------------------------------------------------------91. In Oracle Database 12c, you can create an auto-incrementing column. What would be
a typical use for an auto-incrementing column?
----------------------------------------------------------------------------------92. Make sure you shutdown your database. This frees up server resources for other
students working on their labs.
SQL> shutdown immediate;
-----------------------------------------------------------------------------------