Oracle

Content Software Environment Oracle SCOTT user Select the nth value from the table Select the nth small value from the table  Software Environment Windows Server 2008 R2 Oracle 11g Release 1 (11.1)  Oracle SCOTT user This

I. SQL tuning class 1: List several table Connection MethodsHash join/merge join/nest loop (cluster join)/index join 2: How to view SQL Execution plans without using third-party toolsSet autot onExplain plan set statement_id = & item_id for &

Check the awr report and record the index failure caused by implicit conversion. In awr, statements consume more than 40 million logical reads. Variables are tested quickly. SQL a.order_prod_amount, b.prod_cost_price user_sess a, PR_DO_T b a.prod_

An alarm is reported in the RMAN backup log. The log file directory is as follows: [Root @ erpdbs rmanback] # llTotal 88-Rw-r -- 1 oraprod dba 81011 Sep 7 rmanback. log-Rwxr -- r -- 1 oraprod dba 2581 Jun 24 2011 rmanback. sh[Root @ erpdbs rmanback]

[Oracle] Simple implementation of triggersObjective: To back up data in the uertest table to usertest_temp in real time. The two tables have the same structure. Use the oracle trigger to synchronize data. Result: 1. Create a table? 1 2 3

Oracle Database Export and re-import 1. Export Database? 1 2 3 4 5 6 1. Completely export the database TEST, username scott password tiger, and export it to D: testDB. in dmp: [plain] exp scott/tiger @ TEST file = d: testDB. dmp full

In Oracle, multiple databases can be configured, and only one listener can be enabled. for multiple databases, you only need to configure the corresponding service name to connect. I use Oracle 8.1.7 Enterprise Edition and the OS is a Windows 2000

During database operations, we may encounter this situation, and the data in the table may be repeated, causing a lot of inconvenience during database operations, so how can we delete the useless data?The deduplication technology can provide a

In the process of diagnosing database system performance, SQL statements with low tracking efficiency are always involved. Oracle Database 10 Gb contains a new utility trcsess, it allows you to selectively extract trace data from a large number of

A table connection refers to the association between tables in an SQL statement to retrieve relevant data from one or more tables, in general, the table and table connections can be divided into four types: equal connection, external connection,

Common dump commands in Oracle for future reference. 1. Memory Dumps 1). Global AreaAlter session set events 'immediate trace name global_area level n ';1 Including PGA2 contains SGA4 include UGA8 contains indrect memory 2). Library CacheAlter

LieHuo. Net Oracle tutorialThe database I use is oracle 10.2.0, the global database name is orcl. local, And the SID is orcl. After an instance of the oracle database is created, it can be connected from the local machine, as follows: Sqlplus/nolog

The Oracle database cannot be connected, and related errors are prompted.OERR: ORA-12519 TNS: no appropriate service handler foundClient Connection intermittent failure, error ORA-12519Cause: the listener cocould not find any available service

The tutorial of helping customer House (www.bkjia.com) uses ORACLE stored procedure and JOB to realize automatic backup of data tables. 1. Create a stored procedure Create or replace procedure data_auto_backupV_tablename varchar2 (200 );V_year

View all tables in Oracle:Select * from tab/dba_tables/dba_objects/cat;View the table created by the user:Select table_name from user_tables; // The table of the current userSelect table_name from all_tables; // tables of all usersSelect table_name

Today in the data export, because the user name password is a special character, so encountered the error code: "EXP-00056: encountered ORACLE error 12154", online search for the reason, the quotation marks must be used for expansion, but the

I. Hardware requirements 1. Memory & swap Minimum: 1 GB of RAMRecommended: 2 GB of RAM or more Check memory # grep MemTotal/proc/meminfo # grep SwapTotal/proc/meminfo 2. Hard Disk Since CentOS is installed almost 4 ~ 5 GB, plus Oracle and so on, so

ORACLE locks have the following modes:0: none1: null2: Row-S Row sharing (RS): Share table lock3: Row-X (RX): used for Row Modification4: Share lock (S): blocks other DML operations5: S/Row-X dedicated shared rows (SRX): block other transaction

SQL statement for querying and deleting duplicate records1. Search for redundant duplicate records in the Table. duplicate records are determined based on a single field (Id ).Select * from table where Id in (select Id from Table group by Id having

1. UPDATE nowait: query a piece of data and enable database transactions for it. If no lock is applied to the current data, the system returns the correct result and locks the current data. If the queried data is already in the transaction, the