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Updated: 4 weeks 1 day ago

Log Files in Oracle External Tables

Tue, 2019-10-22 00:46
My External Tables were working fine before i accidentally deleted all the .log and .bad files from the default location. Now I am getting below error ORA-29913: error in executing ODCIEXTTABLEOPEN callout ORA-29400: data cartridge error KUP-...
Categories: DBA Blogs

(Theoretical) Confusion with roles and public synonyms

Tue, 2019-10-22 00:46
Hi Tom, <b>Confusion1:- </b> Suppose I have three user accounts in my database: A, B and C. 'A' user has the privilege to create a role. Suppose there is a table named 'employee' in schema 'A' and 'A' issues:- 1. create role GiveAccess; 2...
Categories: DBA Blogs

Stat gather impact on production environment

Mon, 2019-10-21 12:45
On OLTP production environment, during huge transaction period, what is an impact if we run the stat gather of used schema for transaction???, It will missed any indexes, and other operation issues???
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Best practice for "archiving" legacy tables and their data

Mon, 2019-10-21 12:45
Hi, I recently removed the last piece of front-end functionality that relied on a table, and am certain that that table and its data is no longer needed for the application to function. We'll have more similar tables in this situation in the near ...
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Fetch across commit

Mon, 2019-10-21 12:45
what do you mean by 'Fetch across commit'
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Is there a maximum number of schemas that can be included in a datapump par file?

Mon, 2019-10-21 12:45
I've been tasked with migrating a very large warehouse database (9TB) from hardware in one data center to new hardware in a different data center. For various reasons, the method I've selected for the migration is datapump. I'm breaking up the data...
Categories: DBA Blogs

Index Rebuild and analyze

Mon, 2019-10-21 03:45
Hello Tom , I have a query regarding Index rebuild . what according to you should be time lag between index rebuilds. We are rebuilding indexes every week .but we found it is causing lot of fragmentation. is there any way we could find out whet...
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Views of Views

Mon, 2019-10-21 03:45
I remember hearing some time ago that creating views based upon other existing views should be avoided as it can often confuse the optimiser and result in full table scans. I expect that this is just another urban myth however I would be intereste...
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Inserts with APPEND Hint.

Mon, 2019-10-21 03:45
<code>insert /*+ append */ into t select rownum,mod(rownum,5) from all_objects where rownum <=1000 call count cpu elapsed disk query current rows ------- ------ -------- ---------- ---------- ---------- -----...
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Kill a session from database procedure

Mon, 2019-10-21 03:45
How i can kill a session from a stored database procedure. There is some way to do this?
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Why cost for TABLE ACCESS BY INDEX ROWID to high for only one row

Sat, 2019-10-19 15:45
Dear Tom, I have problem with query on table have function base index. create index : <code> create index customer_idx_idno on Customer (lower(id_no)) ; --- id_no varchar2(40) </code> <b>Query 1:</b> execute time 0.031s but cost 5,149, 1 row ...
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How to get unique values/blanks across all columns

Sat, 2019-10-19 15:45
Hi, I have a wide table with 200 odd columns. Requirement is to pivot the columns and display the unique values and count of blanks within each column <code>CREATE TABLE example( c1 VARCHAR(10), c2 VARCHAR(10), c3 VARCHAR(10) ); / INSERT ...
Categories: DBA Blogs

Elastic search using Oracle 19c

Sat, 2019-10-19 15:45
Team, Very recently we got a question from our customer that "can I replace Elastic search using Oracle 19c or any version of Oracle database prior to that"? Any inputs/directions to that please - kindly advice.
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Add NULLABLE column with DEFAULT values to a large table

Sat, 2019-10-19 15:45
I'm adding a number of columns with DEFAULT values that are NULLABLE to a large table e.g <code> alter table big_table add (col1 varchar2(1) default 0, col2 varchar2(1) default 0); </code> It's taking a long time to do because Oracle is e...
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Create table from select with changes in the column values

Sat, 2019-10-19 15:45
Hello, In the work we have an update script that takes around 20 hours, and some of the most demanding queries are updates where we change some values, something like: <code> UPDATE table1 SET column1 = DECODE(table1.column1,null,null,'no...
Categories: DBA Blogs

Data archival and purging for OLTP database.

Sat, 2019-10-19 15:45
Hi Tom, Need your suggestion regarding data archival and purging solution for OLTP db. Currently we are planning to have below approach. database is size is 150 Gb and planning to run the jobs monthly. 1) Generate flat files from table based on...
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Job to end in case connection not establishing with utl_http.begin_request

Sat, 2019-10-19 15:45
i am tracking around 17000 orders through a web service through pl/sql to a destination server. i am running multiple jobs in batches(for 500 orders each job) for invoking webservice to get the order status. so around 34 jobs are running (17000/500) ...
Categories: DBA Blogs

Inserting values into a table with '&'

Sat, 2019-10-19 15:45
Hi, I want to insert a values into a table as follows: create table test (name varchar2(35)); insert into test values ('&Vivek'); I tried the escape character '\' but the system asks for a value of the substitution variable. I also did a...
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Pivot with list of rows

Thu, 2019-09-26 06:46
We have a table which contains db_name and usernames. In the output we need list of users per DB i.e. number of columns will be equal to distinct db_name. sample output format: <b>DB1 DB2</b> USER1 USER4 USER2 USER5 USER3 Database version:...
Categories: DBA Blogs

confuse at the order of execution plan table

Thu, 2019-09-26 06:46
As we were told that "The execution order in EXPLAIN PLAN output begins with the line that is the furthest indented to the right. The next step is the parent of that line. If two lines are indented equally, then the top line is executed first." howe...
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