Oracle

The following is a detailed analysis of the three methods for creating an Oracle database. For more information, see 1. Create, configure, or delete a Database by running Oracle Database Configuration Assistant (you can also enter dbca in the

After Oracle is installed, there is a default database. In addition to this default database, we can also create our own database. For beginners, you can use the 'database Configuration asmap' Wizard to create a Database to avoid troubles. After

1: differences between char and varchar2: Varchar2: variable-length variable length Char: fixed-length fixed length Memory is allocated when char is defined, while varchar2 dynamically allocates memory. The following example clearly illustrates the

(Tablespace contraction script)] -- 1. obtain information about the tablespace to be released (including the tablespace owned by oracle database) -- Drop table system. tbs_detail; Create table system. tbs_detail as select A. tablespace_name, A.

Oracle has three table connection technologies: Nested connection, merge connection, and hash connection. 1. nested loop Join) Nested connection divides the dataset to be processed into an External Loop (driving data source) and an internal loop

The DBMS_RANDOM package in Oracle encapsulates some functions that generate random numbers and random strings. The following are commonly used: DBMS_RANDOM.VALUE Function This function is used to generate a random number. It can be used in either of

Set oralce Automatic Memory ManagementShutdown and restart are required to enable oracle automatic memory management.1. Determine the sga pga memory size:SHOW PARAMETER TARGET2. determine the maximum pga usage since the database is started:Select

Stateless HTTP protocol 1. Advantages and Disadvantages of stateless HTTP protocol A) HTTP interaction is stateless. Stateless means that when a browser sends a request to the server, the server responds, but the same browser sends the request to

1. Open the corresponding database through plsql. 2. Select the export users objects sub-menu under the menu tools 3. Select the name of the table to be exported and select the saved path. 4. Click the export button to export the selected

Create test tables, which are frequently used by DBAs. Generally, they are created based on dba_objects. This article is based on the big_table of Master Tom for your reference.1. big_table based on Oracle 10 GB --====================================

1. log on to the database using an oracle user [Oracle @ wuzj ~] $ Sqlplus/nolog SQL * Plus: Release 10.2.0.1.0-Production on Thu Feb 26 12:06:29 2009 Copyright (c) 1982,200 5, Oracle. All rights reserved. SQL> conn/as sysdba Connected. // View the

The former is easy to locate. All operating systems allow us to view CPU-intensive tasks. These tasks can be traced back to a specific user, a specific application module. CPU-intensive modules are generally caused by poor code and/or structure,

Code used The Code is as follows:-- Sample dataDrop table t_collect purge;Create table t_collectSelect mod (rownum, 30) as flag, lpad (dbms_random.string ('l', 3), 4, '') as valFrom dual connect by rownum Collect function (Oracle10g)-- 1: use

Resets the oracle sequence from a specified number. The Code is as follows:DeclareN number (10 );V_startnum number (10): = 10000001; -- start from the numberV_step number (10): = 1; -- stepTsql varchar2 (200 );V_seqname varchar2 (200): = 'mip _

-- 19-1: CREATE a FUNCTION without parameters: create or replace function cur_datetimeRETURN VARCHAR2ISBEGINRETURN TO_CHAR (sysdate, 'yyyy "year" MM "month" DD "day" HH24 "Hour" MI "Minute" SS "seconds" '); END;/-- 19-2: create or replace function

1. InstallationOracle.Select custom installation for oracle Installation, then install transparent gateway, and then choose to install components for sqlserver.2. Modify the oraclehomeora92tgsmsqladmininittg4msql. orq FileHS_FDS_CONNECT_INFO =

ISQL * PLUSThe configuration process is as follows:1. Configure HTTPD$ Cd $ ORACLE_HOME/Apache/conf$ Vi httpd. conf1.1 set the Server name or Server IP address and port and start the HTTPD process as a non-root user. The port must be greater than 102

1. The tested statements must be exactly the same as those in the shared pool. 2. Variable names should be as consistent as possible 3. Rational use of external connections 4. Use less multi-layer nesting 5. Multi-purpose concurrency Statement

Normally, when you create a record in a table, the database system writes the data to the block and provides a ROWID value like this row of records. This value records the location of the record stored on the hard disk. This is also true when

Create a trigger in the Oracle DBA Studio tool. CREATE TRIGGERNameCreate trigger-CREATE a new TRIGGERSyntaxCreate trigger name {BEFORE | AFTER} {event [OR...]}ON table for each {ROW | STATEMENT}Execute procedure func (arguments)InputNameTrigger name.