Oracle

Oracle architecture basics 1. physical structures (consisting of control files, data files, redo log files, parameter files, archive files, and password files) data in a database is stored in physical files on disks, when used, it is transferred to

Create table "JCMS_ADVERT" ("ID" integer not null enable, "SITEID" INTEGER, "NAME" VARCHAR2 (150 CHAR) not null enable, "UPDATETIME" DATE, primary key ("ID"); create Table sequence create sequence seq_advert minvalue 1 maxvalue 9999999999999999999999

Database Learning (1) -- Introduction to relational databases, including Oracle databases, MySQL databases, Microsoft SQL Server databases, and DB2 databases. The data model is an abstraction of real-world data features. A complete data model

Oracle SGA automatic management feature (sga_target parameter) 1. related parameter description a. Parameter SHARED_POOL_SIZE = integer [K | M | G] Default value If SGA_TARGET is set: if the parameter is not specified, then the default is 0

Oracle ----- familiar with the basic use of oracle databases, do not come! 1. create a table employee with the following fields: Id number (4), First_Name varchar2 (20), last_Name varchar2 (20), mgrid NUMBER (4), Job varchar2 (20 ), salary number (7,

Before oracle arhivelog mode Backup recovery, let's take a look at the role of archive: 1. when a media fault occurs, it can be restored (whether online or offline, to the specified time point, and to the end of the log file (until cancel. back up

Please record Oracle strings, numbers, special symbols, and sorting problems after they are solved. It may be used at some time. Not to mention, positive T; requirement (changed based on different requirements): Sort string format: field Test course

The simplest way to manage instance memory is to allow the Oracle Database instance to automatically manage and tune it for you. A simple way to manage memory is to allow oracle to automatically manage and optimize the memory for you! To do so (on

File External table analysis if you do not want gpfdist as a server, there is also a simple method-file, directly based on the file path. [Gpadmin @ d1 ~] $ Cat nohup. out Serving HTTP on port 8081, directory/data1/cdrdataServing HTTP on port 8082,

Oracle partition by and partition... order by grouping partition by and partition... difference in order by usage. I just used it. Confused: Table t a B C 1 43 2013-4-17 2 33 2013-4-18 3 10 2013-4-17 use partition by: When rank () is used, use order

Common Oracle exception types: exception description CURSOR_ALREADY_OPEN tries to "OPEN" an opened cursor DUP_VAL_ON_INDEX tries to insert a duplicate value INVALID_CURSOR to "UNIQUE" and tries to operate on the closed cursor INVALID_NUMBER in the

Oracle 11g ora-00979 bug processing migrate oracle 10g Report library to oracle 11g existing Stored Procedure compilation times ora-00979 error, determined to be group by followed by the cursor cannot be used, later I found a bug of 11g with metlink

Oracle indexing technology-Daily notes (2) function indexing SELECT * from demot where F7 = 'F'; SELECT * from demot where lower (F7) = 'F '; there was a bitmap index on F7, but after using the LOWER function, the whole table was scanned. Next we

Oracle Data File Operations 1. view data files and tablespaces SQL> SELECT * from v $ DATAFILE; SQL> SELECT * FROM DBA_DATA_FILES; SQL> SELECT * FROM V $ TABLESPACES; the distribution of data files and the name of the tablespace can be obtained. 2.

ORA-00600: internal error code, arguments: [4194], ORA-00607 solve today there is a kid shoes said their client connection is not on the server end through oral guidance really cannot be done, at that time, I was still angry with the oracle net

Oracle trunc does not perform function processing on the time field, which is very slow and Low-each time a record is extracted, a function must be performed on the time field to determine whether select count (1) is appropriate) FROM

HINT description of ORACLE hints is a mechanism provided by oracle to tell the optimizer to generate an execution plan as we tell it. We can use hints to achieve: 1) Type of optimizer used 2) optimization goal of the cost-based optimizer: all_rows

Greenplum available space computing greenplum theory available database space: Configure mirror: database_size = usable_disk_space/(2 + 1/3) (greenplum needs to reserve some space for the workspace) not configured with mirror: database_size = usable_

All about Oracle ACFS 1) Create the new ACFS diskgroup: [grid @ asmlnx2 ~] $ Sqlplus "/as sysasm" SQL * Plus: Release 11.2.0.3.0 Production on Fri Apr 6 17:38:38 2012 Copyright (c) 1982,201 1, Oracle. all rights reserved. connected to: Oracle

Basic rules for creating indexes in Oracle 1. B-Tree indexes 1. the principle of selecting an index field: select a highly selective field for the join field in the most frequently used field join statement in the WHERE clause (if few fields have