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Multi threading in PLSQL

Tom Kyte - Mon, 2018-07-09 03:26
Team, In current project, one of the batch process procedure is called in Java layer for Multi threading purpose. As current requirement, we need to call same stored procedure in PLSQL layer instead of Java layer. we tried to implement using DBMS...
Categories: DBA Blogs

insert primary key value by trigger

Tom Kyte - Mon, 2018-07-09 03:26
create or replace trigger t_emp_no before insert on emp_info begin insert into emp_info(emp_no) values(s_emp_no.nextval) end; / i tried to entry primary key emp_no values without showing it on oracle 10g form with S_emp_no sequence .Problem is...
Categories: DBA Blogs

Updating salary rows

Tom Kyte - Mon, 2018-07-09 03:26
hello Tom, i wrote that mentioned plsql update salary procedure.It compiled also successfully.But it didn't change any of my salary row.Actually,I am new in programming.I want to know .how does is work. how can i confirm that it is working & how ca...
Categories: DBA Blogs

Equality check and TO_NUMBER bug with trailing CHR(0) on SUBSTR function

Tom Kyte - Fri, 2018-07-06 20:46
Hello Tom ! It seems that Oracle has a bug in TO_NUMBER function on strings with trailing CHR(0). For example it happens when SUBSTR function is used for which there is not defined length parameter. Example: <code>select substr(session_id...
Categories: DBA Blogs

My tmux scripts to script demos

Yann Neuhaus - Fri, 2018-07-06 10:27

When I did my first demo using tmux, I have written the following blog post to explain it: https://blog.dbi-services.com/using-tmux-for-semi-interactive-demos/. Since then I’ve done all my demos with this technique. My scripts and configuration files have evolved now I have uploaded the on GitHub to share them: https://github.com/FranckPachot/scripts/tree/master/tmux-demo

The README.md explains the pre-requisites (a recent version of Tmux), how to download the scripts quickly (I use this to get everything ready on a new Cloud host), and how to run it. The ‘demo’ alias starts tmux attached to the same session (in order to see it on the laptop and the beamer). The .vimrc defines the macros to run lines from the script file as tmux-send commands.

If you have questions, the best is to ask them on Twitter:

Here are the scripts and configuration files I use for my demos with tmux: https://t.co/OuuhHClmt3

— Franck Pachot (@FranckPachot) July 6, 2018

 

Cet article My tmux scripts to script demos est apparu en premier sur Blog dbi services.

New OA Framework 12.2.6 Update 13 Now Available

Steven Chan - Fri, 2018-07-06 09:03

Web-based content in Oracle E-Business Suite Release 12 runs on the Oracle Application Framework (also known as OA Framework, OAF, or FWK) user interface libraries and infrastructure.

We periodically release updates to Oracle Application Framework to fix performance, security, and stability issues.

These updates are provided in cumulative Release Update Packs, and cumulative Bundle Patches that can be applied on top of the Release Update Packs. In this context, cumulative means that the latest RUP or Bundle Patch contains everything released earlier.

The latest OAF update for Oracle E-Business Suite Release 12.2.6 is now available:

Oracle Application Framework (FWK) Release 12.2.6 Bundle 13 (Patch 27948803:R12.FWK.C)

Where is this update documented?

Instructions for installing this OAF Release Update Pack are in the following My Oracle Support knowledge document:

Who should apply this patch?

All Oracle E-Business Suite Release 12.2.6 users should apply this patch. Future OAF patches for EBS Release 12.2.6 will require this patch as a prerequisite. 

What's new in this update?

This bundle patch is cumulative: it includes all fixes released in previous EBS Release 12.2.6 bundle patches.

In addition, this latest bundle patch includes fixes for the following three issues:

  • If a user accesses a nonexistent function via OA.jsp just after an application services restart, any Oracle E-Business Suite URL shows an error page.
  • When a user exports table data using the BNE Export button, a NullPointer exception is raised if the table has a dynamic poplist.
  • If BNE Export is enabled, an InvalidObjAccessException is raised when loading a product page.

Related Articles

Categories: APPS Blogs

Inherit Privileges privilege to PUBLIC

Tom Kyte - Fri, 2018-07-06 02:26
I was doing a query on my database against dba_tab_privs where the grantee was PUBLIC. I noticed that for every user I have in my database, PUBLIC has "INHERIT PRIVILEGES" on that user. Should this be something that is allowed? How exactly is this...
Categories: DBA Blogs

LOB Storage parameters

Tom Kyte - Fri, 2018-07-06 02:26
TOM, I wrote a script to create a table with LOB columns. I specified the LOB storage parameters as follows: <code>CREATE TABLE CONFIGURATION (CFG_ID NUMBER(19,0) NOT NULL ENABLE, CFG_CONTEXT_ID VARCHAR2(255) NOT NULL ENABLE, CFG_...
Categories: DBA Blogs

maximum number of expressions

Tom Kyte - Fri, 2018-07-06 02:26
Hi, I have a this... Select * from MYDB where MYDB.ID IN (1,2,3...5000000) Any way to export without 1000 output lines ?? Thanks
Categories: DBA Blogs

How to manage disable/enable Maximize/Resize in oracle forms?

Tom Kyte - Fri, 2018-07-06 02:26
i need to manage disable/enable Maximize,Resize button by programming in oracle mdi parent forms in 10g. Please give me solution of this problems.
Categories: DBA Blogs

Where is alter session coming from? Every time I log in, I see "Session altered."

Tom Kyte - Fri, 2018-07-06 02:26
Every time I log in to our DB via sqlplus, I see this: $ sqlplus / as sysdba SQL*Plus: Release 12.1.0.2.0 Production on Thu Jul 5 11:48:29 2018 Copyright (c) 1982, 2014, Oracle. All rights reserved. Connected to: Oracle Database 12c E...
Categories: DBA Blogs

Does Oracle 9i Data Guard have real time sync?

Tom Kyte - Fri, 2018-07-06 02:26
Hi We have a Oracle 9i database ,When I set up the data guard I want to use real time sync I got a error .So I want to confirm whether Oracle 9i have this future
Categories: DBA Blogs

update cascade

Tom Kyte - Fri, 2018-07-06 02:26
How do I cascade update on the key fields of linked tables thereby ensuring referencial integrity.
Categories: DBA Blogs

I want to understand this decode function which applied in this query

Tom Kyte - Fri, 2018-07-06 02:26
<code> SELECT a.syrmn, a.orgcode, SUBSTR (a.accode, 1, 3) || '0000000' caccode, SUBSTR (a.accode, 1, 6) || '0000' saccode, accode, DECODE (SIGN (SUM (DECODE (a.sntb, 'D', a.samnt, -a.samnt))), 1, SUM (...
Categories: DBA Blogs

18c: Order by in WITH clause is not preserved

Yann Neuhaus - Thu, 2018-07-05 14:29

For a previous post I’ve run on 18c a script of mine to get the V$MYSTAT delta values between two queries. This script (new version available on GitHub) generates the queries to store some values and subtract them on the next execution. But I had to fix it for 18c because I relied on some order by in a CTE which is lost in 18c.
The idea was to get the statistic names in a Common Table Expression (CTE):

with stats as (
select rownum n,stat_id,name from (select stat_id,name from v$statname where name in (&names) order by stat_id)
)

and query it from different parts of the UNION ALL which generates the script:

select 'select ' from dual
union all
select ' '||decode(n,1,' ',',')||'"CUR'||stat_id||'" - '||'&'||'LAG'||stat_id||' "DIF'||stat_id||'"' from stats
union all
select ' '||',nvl("CUR'||stat_id||'",0) "CUR'||stat_id||'"' from stats
union all

The rowum in the WITH clause is used later to add the comma for all rows except the first one – using decode(n,1,’ ‘,’,’)

But this relied on two assumptions:

  1. the WITH keeps the rows ordered
  2. the UNION ALL keeps the rows ordered

Of course, it would be better to add a number on each part and an ORDER BY at the end of the query. But for better readability, I didn’t.

However, the first assumption is wrong since 12.2 where the optimizer introduced In-Memory Cursor Duration Temp Tables. In the query above, the CTE is materialized because it is used multiple times. And this optimization keeps it in memory. But it seems that this structure does not keep the rows ordered.

Here is an example where I have a 4 rows table:

SQL> create table DEMO as select rownum id from xmltable('1 to 4');
Table DEMO created.
 
SQL> select * from DEMO order by id;
 
ID
----------
1
2
3
4

When I put the same query in a WITH clause, with its ORDER BY, and query it from 2 union all statements, the rows are not ordered anymore:

SQL> with cte as ( select * from DEMO order by id)
select rownum,id from cte
union all
select rownum,id from cte ;
 
ROWNUM ID
---------- ----------
1 4
2 3
3 2
4 1
1 4
2 3
3 2
4 1

The execution plan shows the materialization of the CTE result, and mentions that it is an In-Memory Cursor Duration Temp Table (CURSOR DURATION MEMORY)

SQL> select * from dbms_xplan.display_cursor(format=>'+projection');
 
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID 9uwc06ana6trn, child number 0
-------------------------------------
with cte as ( select * from DEMO order by id) select rownum,id from
cte union all select rownum,id from cte
 
Plan hash value: 4025392480
 
----------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
----------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 4 (100)| |
| 1 | TEMP TABLE TRANSFORMATION | | | | | |
| 2 | LOAD AS SELECT (CURSOR DURATION MEMORY)| SYS_TEMP_0FD9D6640_23D74B | | | | |
| 3 | SORT ORDER BY | | 4 | 12 | 4 (25)| 00:00:01 |
| 4 | TABLE ACCESS FULL | DEMO | 4 | 12 | 3 (0)| 00:00:01 |
| 5 | UNION-ALL | | | | | |
| 6 | COUNT | | | | | |
| 7 | VIEW | | 4 | 52 | 2 (0)| 00:00:01 |
| 8 | TABLE ACCESS FULL | SYS_TEMP_0FD9D6640_23D74B | 4 | 12 | 2 (0)| 00:00:01 |
| 9 | COUNT | | | | | |
| 10 | VIEW | | 4 | 52 | 2 (0)| 00:00:01 |
| 11 | TABLE ACCESS FULL | SYS_TEMP_0FD9D6640_23D74B | 4 | 12 | 2 (0)| 00:00:01 |
----------------------------------------------------------------------------------------------------------------------
 
Column Projection Information (identified by operation id):
-----------------------------------------------------------
1 - STRDEF[22], STRDEF[22] 2 - SYSDEF[4], SYSDEF[0], SYSDEF[1], SYSDEF[120], SYSDEF[0] 3 - (#keys=1) "DEMO"."ID"[NUMBER,22] 4 - (rowset=256) "DEMO"."ID"[NUMBER,22] 5 - STRDEF[22], STRDEF[22] 6 - "ID"[NUMBER,22], ROWNUM[8] 7 - "ID"[NUMBER,22] 8 - "C0"[NUMBER,22] 9 - "ID"[NUMBER,22], ROWNUM[8] 10 - "ID"[NUMBER,22] 11 - "C0"[NUMBER,22]

/*+ inline */

If the CTE is not materialized, the rows are ordered, bit the table is read two times:


SQL> with cte as ( select /*+ inline */ * from DEMO order by id)
2 select rownum,id from cte
3 union all
4 select rownum,id from cte ;
 
ROWNUM ID
---------- ----------
1 1
2 2
3 3
4 4
1 1
2 2
3 3
4 4
 
8 rows selected.
 
SQL>
SQL> select * from dbms_xplan.display_cursor(format=>'+projection');
 
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID 0dad0vwg3k0th, child number 0
-------------------------------------
with cte as ( select /*+ inline */ * from DEMO order by id) select
rownum,id from cte union all select rownum,id from cte
 
Plan hash value: 2913170750
 
------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 8 (100)| |
| 1 | UNION-ALL | | | | | |
| 2 | COUNT | | | | | |
| 3 | VIEW | | 4 | 52 | 4 (25)| 00:00:01 |
| 4 | SORT ORDER BY | | 4 | 12 | 4 (25)| 00:00:01 |
| 5 | TABLE ACCESS FULL| DEMO | 4 | 12 | 3 (0)| 00:00:01 |
| 6 | COUNT | | | | | |
| 7 | VIEW | | 4 | 52 | 4 (25)| 00:00:01 |
| 8 | SORT ORDER BY | | 4 | 12 | 4 (25)| 00:00:01 |
| 9 | TABLE ACCESS FULL| DEMO | 4 | 12 | 3 (0)| 00:00:01 |
------------------------------------------------------------------------------
 
Column Projection Information (identified by operation id):
-----------------------------------------------------------
 
1 - STRDEF[22], STRDEF[22] 2 - "ID"[NUMBER,22], ROWNUM[8] 3 - "ID"[NUMBER,22] 4 - (#keys=1) "DEMO"."ID"[NUMBER,22] 5 - (rowset=256) "DEMO"."ID"[NUMBER,22] 6 - "ID"[NUMBER,22], ROWNUM[8] 7 - "ID"[NUMBER,22] 8 - (#keys=1) "DEMO"."ID"[NUMBER,22] 9 - (rowset=256) "DEMO"."ID"[NUMBER,22]

“_in_memory_cdt”=off

If the CTE is materialized, but the new feature to keep it in memory is disabled, the rows are ordered (but probably by chance – there si no guarantee):


SQL> alter session set "_in_memory_cdt"=off;
 
Session altered.
 
SQL>
SQL> with cte as ( select /*+ materialize */ * from DEMO order by id)
2 select rownum,id from cte
3 union all
4 select rownum,id from cte ;
 
ROWNUM ID
---------- ----------
1 1
2 2
3 3
4 4
1 1
2 2
3 3
4 4
 
8 rows selected.
 
SQL> select * from dbms_xplan.display_cursor(format=>'+projection');
 
PLAN_TABLE_OUTPUT
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID 9uwc06ana6trn, child number 1
-------------------------------------
with cte as ( select * from DEMO order by id) select rownum,id from
cte union all select rownum,id from cte
 
Plan hash value: 4025392480
 
--------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | | | 4 (100)| |
| 1 | TEMP TABLE TRANSFORMATION | | | | | |
| 2 | LOAD AS SELECT | SYS_TEMP_0FD9D664D_23D74B | | | | |
| 3 | SORT ORDER BY | | 4 | 12 | 4 (25)| 00:00:01 |
| 4 | TABLE ACCESS FULL | DEMO | 4 | 12 | 3 (0)| 00:00:01 |
| 5 | UNION-ALL | | | | | |
| 6 | COUNT | | | | | |
| 7 | VIEW | | 4 | 52 | 2 (0)| 00:00:01 |
| 8 | TABLE ACCESS FULL | SYS_TEMP_0FD9D664D_23D74B | 4 | 12 | 2 (0)| 00:00:01 |
| 9 | COUNT | | | | | |
| 10 | VIEW | | 4 | 52 | 2 (0)| 00:00:01 |
| 11 | TABLE ACCESS FULL | SYS_TEMP_0FD9D664D_23D74B | 4 | 12 | 2 (0)| 00:00:01 |
--------------------------------------------------------------------------------------------------------
 
Column Projection Information (identified by operation id):
-----------------------------------------------------------
 
1 - STRDEF[22], STRDEF[22] 2 - SYSDEF[4], SYSDEF[0], SYSDEF[1], SYSDEF[120], SYSDEF[0] 3 - (#keys=1) "DEMO"."ID"[NUMBER,22] 4 - (rowset=256) "DEMO"."ID"[NUMBER,22] 5 - STRDEF[22], STRDEF[22] 6 - "ID"[NUMBER,22], ROWNUM[8] 7 - "ID"[NUMBER,22] 8 - "C0"[NUMBER,22] 9 - "ID"[NUMBER,22], ROWNUM[8] 10 - "ID"[NUMBER,22] 11 - "C0"[NUMBER,22]

So what?

We should never rely on the preservation of the row order except when explicitly documented (like rownum over a subquery with order by). And this In-Memory Cursor Duration Temporary table also works in parallel and RAC, so we can understand that the rows are not read in the same order as they were stored. This is always a problem when we migrate. When something works by chance in a version and not in the newer versions, people usually incriminate the migration, rather than recognizing an old bug in the application, just because it was working before.

 

Cet article 18c: Order by in WITH clause is not preserved est apparu en premier sur Blog dbi services.

ODA fiber interface link detection issue

Yann Neuhaus - Thu, 2018-07-05 11:55

Configuring fiber interfaces during an ODA installation can sometime been challenging. The configuration can depend on the kind of gigabit interface converter (GBIC) and switch been used. In this blog, I would like to show a real case faced during one of our customer deployment, and come with a solution.

Problem

We were facing link detection issue when using the GBIC converter delivered by ORACLE, although using a CISCO GBIC converter could make the link available.
em2 interface was used with a CISCO GBIC.
em3 interface was used with an ORACLE GBIC.

[root@TEST1 tmp]# ethtool em2
Settings for em2:
        Supported ports: [ FIBRE ]
        Supported link modes:   1000baseT/Full
                                10000baseT/Full
        Supported pause frame use: Symmetric Receive-only
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Full
                                10000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: 10000Mb/s
        Duplex: Full
        Port: FIBRE
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: d
        Wake-on: d
        Current message level: 0x00000000 (0)

        Link detected: yes
        
[root@TEST1 tmp]# ethtool em3
Settings for em3:
        Supported ports: [ FIBRE ]
        Supported link modes:   1000baseT/Full
                                10000baseT/Full
        Supported pause frame use: Symmetric Receive-only
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Full
                                10000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: Unknown!
        Duplex: Unknown! (255)
        Port: FIBRE
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: d
        Wake-on: d
        Current message level: 0x00000000 (0)

        Link detected: no

 

Solution

Forcing the interface on 10 Gb and configuring auto-negotiation to false could solve the link detection issue with the ORACLE GBIC converter.
This has been performed by updating both ifcfg-em2 and ifcfg-em3 (stored in /etc/sysconfig/network-scripts) with :

ETHTOOL_OPTS="speed 10000 duplex full autoneg off"

 

Both links could then be detected successfully.

[root@TEST1 ~]# ethtool em2
Settings for em2:
        Supported ports: [ FIBRE ]
        Supported link modes:   1000baseT/Full
                                10000baseT/Full
        Supported pause frame use: Symmetric Receive-only
        Supports auto-negotiation: Yes
        Advertised link modes:  Not reported
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Speed: 10000Mb/s
        Duplex: Full
        Port: FIBRE
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: off
        Supports Wake-on: d
        Wake-on: d
        Current message level: 0x00000000 (0)

        Link detected: yes
        
[root@TEST1 ~]# ethtool em3
Settings for em3:
        Supported ports: [ FIBRE ]
        Supported link modes:   1000baseT/Full
                                10000baseT/Full
        Supported pause frame use: Symmetric Receive-only
        Supports auto-negotiation: Yes
        Advertised link modes:  Not reported
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Speed: 10000Mb/s
        Duplex: Full
        Port: FIBRE
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: off
        Supports Wake-on: d
        Wake-on: d
        Current message level: 0x00000000 (0)

        Link detected: yes

 

SFP28 Ethernet Controller firmware upgrade

The firmware version we were running is the 20.06.04.06.

[root@TEST1 ~]# ethtool -i em3
driver: bnxt_en
version: 1.8.0
firmware-version: 20.6.141/1.8.1 pkg 20.06.04.06
bus-info: 0000:18:00.1
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: no
supports-priv-flags: no

In case of further trouble, a firmware upgrade to 20.08.01.14 version can help, as described in following MOS note.
Using the onboard SFP28 ports on an ODA X7-2 server node (Doc ID 2373070.1)

 

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#Exasol Fail-Safety explained

The Oracle Instructor - Thu, 2018-07-05 10:26

The building blocks of an Exasol cluster are commodity Intel servers like e.g. Dell PowerEdge R740 with 96 GB RAM,12 x 1.2 TB SAS Hot-plug hard-drives and 2 x 10Gb Ethernet Cards for the private network. That’s sufficient to deliver outstanding performance combined with high availability. The picture below shows a 4+1 cluster, one of our most popular configurations:

Exasol 4+1 Cluster

Exasol 4+1 Cluster: Shared Nothing Architecture

Each active node hosts one database instance that works on its part of the database (A,B,C,D) in an MPP way. The instances communicate over the private network. Optionally, the private network can be separated into one database network and one storage network. In this case, the instances communicate over the database network. Notice that the instances access their part of the database directly on their local hard drives, they do not need the private network respectively the storage network for that. The reserve node becomes relevant only if one of the active nodes fails. The local hard drives are being setup in RAID 1 pairs, so single disk failures can be tolerated without losing database availability. Not listed is the license node that is required to boot the cluster initially. After that, the license node is no longer required to keep the cluster running.

If data volumes with redundancy 2 are in use – which is the most common case – then each node holds a copy of the data operated on by a neighbor node:

 Redundancy 2

Exasol 4+1 Cluster: Redundancy 2

If a Master-Segment like A is modified, the Slave-Segment (A’) is synchronized accordingly over the private network respectively the storage network.

Availability comes with a price: The raw disk capacity is reduced by half because of the RAID 1 mirroring and again by half because of the redundancy 2, so you remain with approximately (Linux OS and database software also require a small amount of disk space) 1/4 of your raw disk capacity. But since we are running on commodity hardware – no storage servers, no SAN, no SSDs required etc. – this is actually a very competitive price.

Now what if one node fails?

 Node failure

Exasol 4+1 Cluster: Node failure

ExaClusterOS – Exasols Clusterware – will detect the node failure within seconds and shutdown all remaining database instances in order to preserve a consistent state of the database. Then it restarts them again on the still available 3 nodes and also on the Reserve node that now becomes an Active node too. The database itself becomes available again with the node n15 now immediately working with segment B’.

The downtime of the system caused by the node failure is below 30 seconds typically. The restart of the database triggers a threshold called Restore Delay which defaults to 10 Minutes. If within that time the failed node becomes available again, we will just re-synchronize the segments (A’ and B in the example) which can be done fast. The instance on n15 will then work with the segment B as a Master-Segment until the cluster is manually restarted. Then n15 becomes a reserve node again and n12 is active with an instance running there.

If the failed node doesn’t come back within Restore Delay:

 Restore Delay is over

Exasol 4+1 Cluster: Restore Delay is over

We will then create new segments on node n15: A’ is copied from n11 and B is copied from n13. This activity is time-consuming and puts a significant load on the private network, which is why configuring a dedicated storage network may be beneficial to avoid a drop in performance during that period. A new reserve node should now be added to the cluster, replacing the crashed n12.

Categories: DBA Blogs

ORA-01652 unable to extend temp

Tom Kyte - Thu, 2018-07-05 08:06
Hi Team, I went through some weird situation where I am not able to figure out the reason behind error ORA-01652 unable to extend temp. While executing a PL/SQL block at one point I am facing this issue. ORA-01652 unable to extend temp. Whi...
Categories: DBA Blogs

CentOS as the Operating System for Oracle 12.2 database server

Tom Kyte - Thu, 2018-07-05 08:06
Hello Experts, We are planning to install Oracle <b>12.2</b> database server on a Linux <b>CentOS 7.4</b>. <b>My first question</b> May I know whether this setting is supported by Oracle? I've already noted that this OS is not listed under t...
Categories: DBA Blogs

Exadata and direct path read

Tom Kyte - Thu, 2018-07-05 08:06
Hi Tom, In order for smart scan to be achieved , mainly two thing should happen : 1 - The optimizer should choose to full scan the table. 2 - Scanning the data should be done using direct path read. The first requirement is quit simple , bu...
Categories: DBA Blogs

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