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Questions tagged [exadata]

Oracle Exadata is a database appliance with support for both OLTP (transactional) and OLAP (analytical) database systems.

Oracle Exadata is a database appliance with support for both OLTP (transactional) and OLAP (analytical) database systems.

It was initially designed in collaboration between Oracle Corporation and Hewlett Packard, where Oracle designed the database, operating system (based on the Oracle Linux distribution), and storage software whereas HP designed the hardware for it.

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Performance test sql queries

We have two identical Oracle Exadata quarter racks each running a pair of database instances. My wet-finger-in-the-wind performance tests indicate that one is running at a quarter of the speed of the other. Is there a set of SQL queries that can be…
grenade
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Java applications on Oracle Exadata

For reasons that are beside the point, a company has bought an Exadata Eighth Rack. Some of the managers thought that this would improve performance of current applications. The problem is that hardly any application makes intensive database work…
sinuhepop
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Window functions SORT costly, can we overcome it?

My Requirement: Identify top 10 accounts of a DEPT_NUM , ordered by the account number in ascending order. Query: SELECT * FROM ( select acctnum,dept_num,row_number() OVER (PARTITION BY DEPT_NUM ORDER BY ACCTNUM) as row_identifier FROM…
Maheswaran Ravisankar
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Oracle Exadata - LEFT OUTER JOIN acting like INNER when using AND on join condition

Background Recently my company upgraded from Oracle 11g to Exadata. All production objects and data were successfully migrated to the new system and were verified to be a 1:1 match between systems. Immediately after the first daily set of ETL…
Chad Stewart
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Subselect (instead of numeric constant) worsens optimization

My question is similar to To subselect or not to subselect? but I would like keep using the two existing views (hence I don't want to move the subselect directly into the view logic). Slow (1.5 seconds) SELECT h.n FROM v_headers h WHERE h.n >=…
Andrei Damian-Fekete
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Oracle DB on Exadata. update running for hours, parallel hint isn't working

We have two huge tables and trying to update around 60 million records. It used to update in 30 minutes before and now its taking hours n hours, Not even more than 20% of data growth. Here is more information. I see that there is a lot of wait on …
user3570198
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Parallel execution not speeding up full table scan in Exadata

Suppose I have one very large table, with 250M rows: create table example_customers as select dbms_random.string('x', 100) as first_name , dbms_random.string('x', 100) as last_name from dual connect by level <= 250000000; begin …
EdG
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How to size connection pool against Oracle Autonomous Database (ATP)?

If I have an Oracle Autonomous Database in an exadata vm with 1 OCPU, how should I configure my jdbc connection pool? How many connections should I specify? What is the maximum amount?
David Fdez.
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Impact of COUNT() Based on Column in a Table

Edit: Database - Oracle 11gR2 - Over Exadata (X2) Am framing a problem investigation report for past issues, and I'm slightly confused with a situation below. Say , I have a table MYACCT. There are 138 Columns. It holds 10 Million records. With…
Maheswaran Ravisankar
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Using listagg (colname,',') in creating a table is throwing error ORA-01489: result of string concatenation is too long

I am trying to create a table using following query: select base.Col1, base.dt_date,acct.Col2,acct.col3, listagg (acct.e_indic,',') within group (order by acct.e_indic) as e_indic from tab1 base, (select dt_date, act, sum(Col4) sets from tab2…
Rohith Manderwad
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How do I connect to Oracle Exadata from Python?

I have tried connecting exadata from python using cx_Oracle, but faced issue stating cx_Oracle.DatabaseError: DPI - 1047: Cannot locate a 64bit Oracle client library. I am trying to install a 64bit cx_Oracle, but I need to know can I connect from…
Vishnu kanth
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Creating a new calculated column in a oracle exadata table with 3 billion rows

I have a table in Oracle exadata with 3.4 billion rows. I need to create a new column in this table which is the sum of the other 2 columns in the table. I tried the below. - Create column using alter table add column. - Update table set column C =…
Sawan S
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Oracle database 12c "compress for query" OPTION

I have a development server on a simple server with oracle 12c and our production server is on Oracle Exadata. On some of the tables we use COMPRESS FOR QUERY option. My problem is every time we create a table we need to remove this option(from DDL)…
nipuro
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Role to access the table only but not data from Table in Oracle Exadata

Users have create table statement with select statement from multiple tables from multiple schema. I want to restrict them to read data and allow them to create empty table in their schema with metadata only not data. This I want to do at user…
v83rahul
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Using dbms_scheduler.create_credential on a exedata

I want to setup a file_watcher for file created in a location in the OS. We are currently using Jobs that access the files through utl_file.fopen to access the files using a directory entry. I ask my DBA to setup a credential so I can establish the…
Stephen Brower
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