Oracle

The recent optimization of Oracle database efficiency, and then on the Internet to check the existence of a number of high-efficiency methodsThere are a lot of suggestions on the Internet first method, I did a test, but probably not enough data

Function:1.translateSyntax: TRANSLATE (char, from, to)Usage: Returns the string from which each character appearing in the From is replaced with the corresponding character in to.If the from is longer than the to string, then the characters that are

Permissions:Create sessionCREATE tableUnlimited tablespaceConnectResourceDbaCases:#sqlplus/nologSql> Conn/as sysdba;Sql>create user username identified by passwordSql> Grant DBA to username;Sql> Conn Username/passwordSql> select * from

---restore content starts---Now large enterprises generally use Oracle database, Oracle database in the general use of EXPDP,IMPDP Export import data, but in the operation often encountered some problems. The following is an analysis of these

Wrote a program: read a table in SQL Server based on the status bit, download the value of one of the fields, this value is XML type, then insert the contents of the XML file into another Oracle database, and update the SQL Server table flag,

Official Document: http://docs.oracle.com/cd/E11882_01/server.112/e41573/technique.htm#PFGRF941381. ADDM will give the optimization advice2. How to find system bottlenecks:Step1. Is the system's response time acceptable when a single user or system

The main is to summarize the Oracle functions used in the project, and make a directory, so that the follow-up project is quick to find and improve efficiency.01.Round (rounding of values)Description: Returns a numeric value that is the result of

 View Tablespace usageSelect Upper (F.tablespace_name) "Table space name",D.TOT_GROOTTE_MB "Table space Size (m)",D.tot_grootte_mb-f.total_bytes "used Space (m)",To_char (Round (d.tot_grootte_mb-f.total_bytes)/d.tot_grootte_mb * 100,2),' 990.99 ')

1. Open Oracle Related services2. Create Oracle UsersCreate user username identified by password; (DBA role creation required)3. Rights Management(1) Add permissionsGrant permissions, role to user name [with ADMIN option] (System permissions);Grant

2016-02-16Relationship Division R÷sRelationship mode R (x, y) S (y,z)Meaning: Querying tuples in R that are related to all tuples in sFirst, create the base table R and SCREATE TABLER (XVARCHAR2(Ten), YVARCHAR2(Ten));CREATE TABLES (YVARCHAR2(Ten),

Original Url;http://www.oschina.net/question/30362_4057?fromerr=fiy27yllAuthor: CrazyinsomniaFirst, the concept of ROWIDStores the location of row in the data file: 64-bit encoded data, A-Z, A-Z, 0-9, +, and/,How row is stored in the data

Data is the core of the application, the program is broken the re-release of the machine can be, but once the loss of data, the loss will be irreversible, the program released to production, data backup is particularly important, because not all

Turn from: How Oracle writes Efficient SQLTo write efficient SQL statements requires some basic principles, and if you violate these principles, SQL will typically have poor performance.1. Reduce database access timesConnecting to the database is

Original sql:Select substr (field1, InStr (field1, ' | ', 1, rownum) + 1, InStr (field1, ' | ', 1, rownum + 1)- InStr (field1, ' | ') , 1, RowNum)-1) as Field2 from (select ' | ' | | ' A|bbb|cccc|ddddd|ee|d|a '

Format: Numtoyminterval (n, Interval_unit); N: Numeric type Interval_unit: ' Year ', ' MONTH ', or other expression that can be converted to one of these two values Numtoyminterval (1, ' Year '): Interval numtoyminterval ( -1, ' month '): One months

differences and linkages between Oracle unique indexes and ordinary indexesDifference: Unique index and general index the biggest difference is that you add a single layer of constraint to the index column. A data column that adds a unique index can

[Translated from mos] the TCP port used by the OGGreplicat ProcessTCP port used by the OGG replicat ProcessSource:Tcp port used by replicat processes (Document ID 1060954.1)Applicable:Oracle GoldenGate-Version 10.4.0.12 and laterInformation in this

[Translated from mos] "WARNING: Noclusterinterconnecthasbeenspecified" appears in the alert log of the database instance" "WARNING: No cluster interconnect has been specified" appears in the alert log of the database instance" Source:No Interconnect

[Translated from mos] OracleGoldenGate's support for IBM mainframe z/OS2.1 and DB2v11 GoldenGate support for IBM mainframe z/OS 2.1 and DB2 v11Source:GoldenGate Support for z/OS 2.1 and DB2 v11 (Document ID 1941364.1) Applicable:Oracle

Two methods for creating Database Link in Oracle are described in detail. Create A dblink named dblink_name, which is connected from database A to database B. Database B has the IP address 192.168.1.73, port 1521, Instance name oracle, login name