By Thomas Kyte, Darl Kuhn
Oracle Database Transactions and Locking printed presents much-needed info for construction scalable, high-concurrency purposes and install them opposed to the Oracle Database. learn this brief, 150-page publication that's tailored from professional Oracle Database structure to achieve an excellent and actual figuring out of the way locking and concurrency are handled by way of Oracle Database. additionally learn the way the Oracle Database structure contains consumer transactions, and the way you could write code to mesh with how Oracle Database is designed to function. reliable transaction layout is a crucial part of highly-concurrent purposes which are run by way of hundreds and hundreds, even hundreds of thousands of clients who're all executing transactions while. Transaction layout in flip depends a very good knowing of ways the underlying database platform manages of the locking of assets in an effort to hinder entry conflicts and information loss that would another way consequence from concurrent entry to info within the database.
Read or Download Oracle Database Transactions and Locking Revealed PDF
Best oracle books
This can be a outstanding ebook, transparent and well-written. it really is basic adequate for these with no a lot adventure, but additionally offers sufficient element when you don't want coddling. .. certainly, definitely worth the $.
At the present time DBAs are anticipated to set up and deal with huge databases with caliber provider and little to no downtime. The DBA’s major concentration is on expanding productiveness and doing away with idle redundancy in the course of the company. besides the fact that, there's no magic set of top practices or challenging and speedy principles that DBAs have to stick with, and this may make existence tough.
It’s occasionally acknowledged that the genuine activity of an Oracle database administrator may be summed up in a single, crucial ability: so one can recuperate your database.
There’s a lot knowledge in that assertion. Of every little thing you're accountable for as a database administrator, not anything is extra vital than the knowledge itself. love it or no longer, the fearsome accountability of defending your agencies most crucial info falls squarely upon your shoulders:
- Lose that facts and your organization may perhaps fail.
- Lose that information and also you might be out of a job.
Scared? you need to be. yet theres aid. you're not on my own. Oracle specialists Darl Kuhn, Sam Alapati, and Arup Nanda have come jointly during this publication to teach you the ability of restoration supervisor, or RMAN, that is Oracles backup and restoration instrument of selection. RMAN Recipes for Oracle Database 11g is helping you are taking benefit of all that RMAN has to supply via delivering easy-to-understand recommendations to business-critical backup and restoration operations. this useful guide
- Demystifies the stairs required to guard your corporation data
- offers ready-made and step by step strategies to basic and intricate backup, fix, and restoration operations
- Is task-oriented, making it effortless so you might uncover the answer to urgent backup and restoration problems
- Respects a while by way of delivering example-based suggestions, now not never-ending analyzing material
When the pressure’s on, you dont have time for lengthy discussions of idea. This booklet will get correct to the purpose with fast and easy-to-read, step by step suggestions that could assist you backup and recuperate your info with confidence.
What you’ll learn
Oracle Database specialists Darl Kuhn, Sam Alapati, and Arup Nanda express you the way to
- Reliably again up and get better your database utilizing Oracles restoration Manager.
- make the most of New Oracle Database 11g positive factors equivalent to the knowledge restoration Advisor.
- allow Oracle Database deal with your backup documents through the Flash restoration Area.
- Automate backup and restoration projects by means of writing scripts.
- Troubleshoot RMAN difficulties and optimize RMAN performance.
- Interface with a Media administration Layer to control your backup tape library.
- get over the lack of a keep an eye on dossier, lack of a web redo log, and different (hopefully! ) strange situations.
Who is that this e-book for?
Oracle database directors chargeable for database backup and restoration operations.
Maximize Oracle Exadata services Leverage the entire robust good points to be had within the Oracle Exadata Database computer utilizing the confirmed suggestions within this Oracle Press advisor. Written through Oracle specialists, reaching severe functionality with Oracle Exadata exhibits you ways to take complete good thing about this entire, optimized package deal of software program, servers, and garage.
- Expert Oracle Application Express Plug-Ins: Building Reusable Components
- Expert Oracle GoldenGate (Expert's Voice in Oracle)
- Oracle SQL: Jumpstart with Examples
- Expert PL/SQL Practices: for Oracle Developers and DBAs
Extra info for Oracle Database Transactions and Locking Revealed
The RBS, SLOT, and SEQ values match the V$TRANSACTION information. This is my transaction ID. Now we’ll start another session using the same username, update some rows in EMP, and then try to update DEPT: EODA@ORA12CR1> update emp set ename = upper(ename); 14 rows updated. info Chapter 3 ■ Lock Types We’re now blocked in this session. username = USER; USERNAME SID RBS SLOT SEQ LMODE REQUEST --------------- ---------- ---------- ---------- ---------- ---------- ---------EODA 17 2 27 21201 0 6 EODA 22 2 27 21201 6 0 EODA 17 8 17 21403 6 0 EODA@ORA12CR1> select XIDUSN, XIDSLOT, XIDSQN from v$transaction; XIDUSN XIDSLOT XIDSQN ---------- ---------- ---------2 27 21201 8 17 21403 What we see here is that a new transaction has begun, with a transaction ID of (8,17,21403).
EODA@ORA12CR1> exec p PL/SQL procedure successfully completed. The procedure, P, will now show up in the DBA_DDL_LOCKS view. We have a parse lock on it: EODA@ORA12CR1> select session_id sid, owner, name, type, 2 mode_held held, mode_requested request 3 from dba_ddl_locks 4 where session_id = (select sid from v$mystat where rownum=1) 5 / SID OWNER NAME TYPE HELD REQUEST ------ -------- --------------------- -------------------- ---------- -------22 EODA P Table/Procedure/Type Null None ... 22 SYS DATABASE 18 Null None 9 rows selected.
If argument A is not null, then it returns argument B; otherwise, it returns argument C. This query assumes that the owner of the constraint is the owner of the table and index as well. If another user indexed the table or the table is in another schema (both rare events), it will not work correctly. info Chapter 2 ■ Locking and Issues The prior script also checks to see if the index type is a B*Tree index (NORMAL or NORMAL/REV). We’re checking to see if it’s a B*Tree index because a bitmap index on a foreign key column does not prevent the locking issue.