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7
votes
4answers
6k views

Multiple operations using WITH

Is there a way to execute multiple operations using the WITH statement? Something like WITH T AS ( SELECT * FROM Tbl ) BEGIN OPEN P_OUTCURSOR FOR SELECT * FROM T; SELECT COUNT(*) INTO ...
7
votes
1answer
297 views

What is “SAP on Oracle”

OK, total newb question. What is "SAP on Oracle", exactly. This link is talking about how SAP can run on Oracle (I think). I'm not understanding how this is working. My understanding: SAP is a ...
7
votes
2answers
6k views

How to extract Procedure, Function, etc. Source Code from an Oracle Export

I have generated an EXPDAT.DMP file of an Oracle database with the command: exp userid=usr/pass@db owner=own rows=n compress=n I then ran the following command to generate a file containing the ...
7
votes
1answer
3k views

Why does an Oracle database require both the SYSTEM and the SYSAUX tablespaces?

Quoting from Oracle documentation about logical storage structures: A database must have the SYSTEM and SYSAUX tablespaces: Why is it compulsory to have these tablespaces?
7
votes
1answer
33k views

Importing schema to new or different tablespace

Is there a convenient way to import a schema into Oracle 11gR2 using a single new or different tablespace than where the data originated? As an example, I have exported BLOG_DATA from OLDDB, where ...
7
votes
3answers
290 views

How do you protect against malicious PREPROCESSOR attacks in Oracle External Tables?

I'm a new DBA and I recently found out about the option of External Tables in Oracle using the PREPROCESSOR feature ( ...
7
votes
2answers
9k views

Oracle 11g: performance improvements of inserts

I have a table of 500 millions of rows (and growing) I did the following to improve performance of inserts: On database side: dropped all indexes and constraints disabled logging On application ...
7
votes
2answers
24k views

How and when to use sys_refcursor in oracle

Can some one give me a small explanation about how and when should someone use sys_refcursor ?
7
votes
1answer
164 views

Cardinality is so far off from reality

I've got a table where the cardinality for plans just seems waaaaaay too high - despite updating stats and even trying dynamic sampling for Oracle 11gR2. select count(*) from table1 where col1 = ...
7
votes
3answers
1k views

What methods are available to create a snapshot of an oracle database for testing purposes?

I am new to databases and have just been assigned to work with Oracle. We want to create a snapshot of the database for testing purposes that will allow us to revert back once we're done. I'm a bit ...
7
votes
3answers
5k views

ORA-04031: unable to allocate bytes of shared memory (“”,“”,“”,“”)

I am receiving this error in a development database. It happens on some specific queries (simple inserts and deletes via .NET application). The database is used by one user, and error happens ...
7
votes
2answers
5k views

Oracle's Merge v. Select->Update/Insert

What is the faster statement? A MERGE or Select->Update/Insert depending on if it returns a value? I'm trying to optimize a database, but I haven't found any speed tests comparing the two. I found ...
7
votes
2answers
60 views

Oracle 10g: Is it possible to designate a undo point?

I was wondering if it is possible to designate a point in time, then later "roll-it-back" to that state (undo DDL and DML changes). Maybe using a record of changes and then executing the reverse? Does ...
7
votes
2answers
276 views

Why is Oracle using the index here?

Name Null Type -------- -------- --------- ID NOT NULL NUMBER(4) GROUP_ID NUMBER(4) TEXT CLOB There is a btree index on group_id. Here's how many ...
7
votes
1answer
908 views

Can I use Oracle Standard or Enterprise edition for my own training purposes?

Question is about Oracle licensing terms. I would like to learn more about Oracle Database administration. Unfortunatelly I am using 32 bit verison of LInux, so I can't install Oracle 11 XE (I can't ...
7
votes
2answers
395 views

Exporting database Oracle 7.3 on Windows NT 3.51

How to take dump files on Oracle7.3 running on Windows NT 3.51? Should you stand in the Orant/bin folder and run one of the programs there like> exp73 SYSTEM/password@[dbinstance] FULL=Y ...
7
votes
1answer
23k views

PLS-00306 Error: How to find the wrong argument?

PLS-00306: wrong number or types of arguments in call to 'string' Cause: This error occurs when the named subprogram call cannot be matched to any declaration for that subprogram name. The ...
7
votes
3answers
163 views

Tablespace on ephemeral storage

For performance reasons in some scenarios, e.g. Amazon EC2, you have access to a faster and cheaper storage device, which loses all its data on reboots, so it is called "ephemeral". This question is ...
7
votes
1answer
897 views

Map Oracle roles to Active Directory groups?

Is there any built-in way to map Oracle database roles to Microsoft Active Directory groups?
7
votes
2answers
8k views

Can I use OpenLDAP to authenticate users in Oracle?

I like to use OpenLDAP to authenticate my Oracle users. It should be possible to fetch at least the password from the directory. There appearently is something for the Oracle LDAP servers, but would ...
7
votes
1answer
25k views

How to free up disk space? which logs/directories to clean?

I want to free up the disk space on my Linux machine. I've drill down the space usage and found that the following directories have a big size /u01/app/11.2.0/grid/cv/log ...
7
votes
1answer
2k views

Generate XML using Oracle XML schema

I have some XML schema definitions that have been registered using DBMS_XMLSCHEMA. I have created tables using the XMLTypes generated. I can create XML using XMLQuery and if I understand correctly, ...
7
votes
1answer
1k views

Find active values of SQLNET.ORA parameters on server

How can I find the active values of SQLNET.ORA parameters on the server? I know how to find the SQLNET.ORA file but there's no guarantee the values in that file are actively used. Parameter changes ...
7
votes
4answers
17k views

Oracle returns an error ORA-01031: insufficient privileges

Oracle returns an error "ORA-01031: insufficient privileges" When I run sqlplus / as sysdba but sqlplus sys/oracle123 as sysdba doesn't, why? Oracle version: Oracle Database 10g Enterprise Edition ...
7
votes
1answer
2k views

What is the meaning of “select * from relational(owner.table)”?

We recently got some errors in our alert log of the form 301598: Tue Jul 16 03:58:29 2013 301599: ORA-01555 caused by SQL statement below 301600: SELECT * FROM ...
7
votes
2answers
617 views

Update all rows

I want to know the most efficient manner to update every row in an extremely large Oracle table for a single column. For example: update mytable set mycolumn=null; or: update mytable set ...
6
votes
2answers
4k views

A database in MySQL is a schema in Oracle : I do not understand this statement

Please help me understand this statement: A database in MySQL is a schema in Oracle. I have just started to use Oracle and I find it different from other RDBMS softwares I have used like MSSQL, ...
6
votes
3answers
32k views

What are the causes and solutions for mutating table errors?

I understand mutating table errors are caused by a design flaw or problematic query. An old query was recently put into production which throws a mutating table error. Our DBA solved the problem but ...
6
votes
4answers
1k views

Does an IOT guarantee order in a select?

We need to add a priority column to a table that gets hit about 250 times a second, approx 170 selects, 125 inserts and 60 updates. The column will be a simple number(1). The priority does not matter ...
6
votes
2answers
6k views

Is Oracle DB licensing needed for a test environment?

I'm planning to setup an Oracle Standard Edition instance on a server in our test environment. Do I need to purchase a license for this?
6
votes
2answers
207 views

How the indexes are managed?

I am trying to understand how the indexes are managed for below common data types: 1- Numeric (Integer, Decimals) 2- String (Varchar, Char) 3- DateTime I have few questions: 1- How the indexes are ...
6
votes
3answers
68k views

Oracle SQL - CASE in a WHERE clause

Is it possible to somehow do this? WITH T1 AS ( SELECT 1 AS SEQ, 'NOTHING 1' AS SOME_TYPE FROM DUAL UNION ALL SELECT 2 AS SEQ, 'NOTHING 2' AS SOME_TYPE FROM DUAL UNION ALL SELECT 3 AS SEQ, ...
6
votes
2answers
32k views

How to get a list of locked accounts / check that account is locked?

I can use following statement to unlock an account: ALTER USER username ACCOUNT UNLOCK But which statement can I use to verify that account is currently locked out?
6
votes
2answers
13k views

When a record is locked in Oracle, can we know which record is locked?

When a record is locked ,can we know which one is locked? How can I get the record rowid or something else info? I can get some info by this sql SELECT ...
6
votes
1answer
6k views

How can I query names using regular expressions?

How could I search for a specific pattern in a column? For example, I like to get all user names that start with either letter A or B. (btw: this is tagged oracle, but it might be interesting in ...
6
votes
2answers
26k views

How to set an Oracle user's default schema?

I created a few new users in Oracle. However, when running sqlplus, they all need to fully qualified the table names in query. What's the best way to set a default schema for these new users?
6
votes
4answers
2k views

How to document Oracle database?

I'm new to Oracle databases. I have used to SQL Server and the description fields (MS_Description) for tables and columns for documentation purposes. Is there an equivalent for Oracle? What is the ...
6
votes
3answers
974 views

Is there a need to keep refreshing the indexes from time-to-time?

This question is common for all the database products I use, viz. SQL Server, MySQL, Oracle and PostgreSQL. I have created a fresh database and the tables, at present, have no records. I have created ...
6
votes
3answers
694 views

What are the top 5 design decisions which need to be made when implementing a database?

I am implementing an Oracle System to store event alerts from an application so I guess all the schema, database design will be handled by the application through a sript. I am new to Database ...
6
votes
4answers
16k views

Building Dynamic Oracle Where Clause

I'm working on application that uses dynamic query to do a select statement based on user input, after discussing security with DBAs they want me to convert my dynamic select statement into Stored ...
6
votes
2answers
103 views

Will the Oracle optimizer still plan a join if I'm not reading any columns in the joined table?

Suppose I have the following view: CREATE VIEW dummy AS SELECT a.some_column, b.other_column FROM a LEFT JOIN b USING (key_column); When I do a SELECT some_column FROM dummy, is there a way to ...
6
votes
2answers
4k views

How do I query to pull all data in row based MIN and MAX service date?

I'm very new to Oracle SQL especially in the Pentaho report builder. It lets you do some things and block others. PL/SQL is not available so I must do this in a query. I need to be able to pull ...
6
votes
2answers
37k views

How do you get the explain plan?

Can some one please explain a bit about explain plan, and how does one get the explain plan for a query. Also, if there is any sql script which can be used as utility for this, that would be great.
6
votes
3answers
2k views

Clustered index in SQL Server vs index organized tables in Oracle

I am making the transition as a database developer from SQL Server to Oracle and found some fantastic resources here already (How to make a transition from SQL Server DBA to Oracle? and As a DBA, how ...
6
votes
2answers
1k views

Does it make sense to consolidate Oracle databases?

I am more experienced with SQL Server and Sybase than Oracle, and understand those products well. I've been asked to look for ways to reduce the server estate running Oracle. I understand that an ...
6
votes
5answers
20k views

Simplified/automated datafile free disk space reclaim

On Oracle version 11g: After Googling, I can't find a simple way to reclaim free space after deleting a table. I've found a lot of explanations, telling how the datafile becomes fragmented, the big ...
6
votes
2answers
1k views

SQL ANSI JOIN precedence

I have a query that looks like this: SELECT * FROM TBLA A LEFT JOIN TBLB B ON A.Col1 = B.Col2 RIGHT JOIN TBLC C ON B.Col3 = C.Col4 JOIN TBLD D ON C.Col5 = D.Col6 In which order ...
6
votes
2answers
2k views

Oracle clean up

I have an Oracle database on a VMWare image that seems to be slowly eating all my available disk space. I would like to know if there is a command or script that would perform some kind of clean up of ...
6
votes
3answers
31k views

How to find the actual space being consumed by indexes on a table in Oracle?

I want to find the actual space being consumed by indexes on a table in oracle 10g . I do not intend to include the space reserved by oracle for future usage. (The overhead by oracle should not be ...
6
votes
4answers
34k views

Oracle startup error (could not open parameter file)

I installed the Oracle 11g server on Ubuntu 12.10. But I can't start the server. When I start up the server, the following error occurs. SQL> startup ORA-01078: failure in processing system ...