Oracle

This article reproduced http://www.it165.net/database/html/201212/3385.htmlFirst, pre-installation preparation work:1. Modify the computer name:The computer name of the server is important for logging on to the Oracle database! remember!(1) After

First, the conceptA tablespace is a logical part of a database.Physically, the database data is stored in the data file;Logically, the database data is stored in a table space, and the tablespace consists of one or more data files.Second, the

I. Maintaining the integrity of the dataData integrity is used to ensure that database data complies with certain commercial and logical rules, and in Oracle, data integrity can be implemented using three methods of constraints, triggers,

1, if you need to create a global DBLink, you need to first determine the user has the right to create DBLink: SELECT * from User_sys_privs where privilege like upper ('%database link% '); If not, you need to use the SYSDBA role to

Detailed code:Import java.sql.Connection;Import Java.sql.DriverManager;Import java.sql.PreparedStatement;Import Java.sql.ResultSet;Import java.sql.SQLException;public class Dbutil () {private static final String classname=

First, IntroductionA logical backup is the process of exporting the structure and data of a data object to a file using the tools export.Logical recovery refers to the process of importing a data object into a database using a backup file when the

In this case, make a data patch, copy the contents of one of the fields in the table to another field, and add a newline if the target field has values.First, the carriage return in Oracle is CHR (13), the newline character is Chr (10), the carriage

First, what is a businessTransactions are used to guarantee the consistency of data, which consists of a set of related DML statements that are either all successful or fail altogether in the group's DML (data manipulation language, additions and

I haven't got up yet, the damn phone is ringing. A nervous message:dataguard database Master never synchronized, quickly climbed up to work. first step, check the alarm log Log.xml . Keep your eyes wide open and look for the abnormal output, and

This package has 11 functions or storage in 11GR2:1. Returns a ROWID based on the given parameters--returns a ROWID based on the given parameterFUNCTIONRowid_create (Rowid_typeinch Number,--rowid type, 0:restricted,1:extendedObject_numberinch

1. Row migrationWhen an update is issued to increase the number of records, the remaining space in the block is not sufficient to hold this record, it will result in a row migration, the ROWID will not change when the row is migrated, the original

1. On the server where Oracle is installed, configure the connection mode to [Shared server mode] through the Database Configuration Assistant tool, so that the Oracle database service supports sharing!！！ Error may occur: Enterprise Manager

ORACLE Date functionSysdate the current database system timeAdd_months (plus minus the specified month)Months_between (number of months separated by two dates)Last_day (the last day of the month on which the specified date is taken)Example

1. Silent File[email protected] ~]$ cat create_template_db.rsp [general]responsefile_version = "12.1.0" Operation_type = " Createtemplatefromdb "[createtemplatefromdb]sourcedb =" rhndb "sysdbausername =" System "Sysdbapassword =" abcABC12 "

Oracle Two optimization modesThe WHERE clause in 1.CBO CBO mode has no effect on query speed2.rbo will perform the index first under Rbo.OLTP online transaction processing refers to systems that frequently change data.OLAP table Data Analysis Index

A summary of the Oracle timer call stored procedures, if there is insufficient place, I hope that we have a lot of guidance, but also the first time in the blog to write something, before it was just a summary of the hard disk, and later colleagues

Original: Lixx---query data from the Unwiredata table if the geomagnetic state in the table changes (cardstate) execution is inserted into the maintable table---judge by the unique value Erid, if the Erid value exists, modify the geomagnetic state

Modify the syntax of the field: ALTER TABLE tablename modify (column datatype [default value][null/not null],....);Syntax for deleting a field: ALTER TABLE tablename drop (column);Add, modify, and delete multiple columns, separated by commas.Use

phenomenon : Students who have used Oracle in a multi-lingual environment must have encountered such a problem,Date_v date;Date_v: = to_date (' 2010/11/16 ');--or ' 2010/11/16 'The same server, different Oracle clinet does not necessarily work.cause

#刚开始直接root用户登录, in the ETC directory, switch to Oracle, enter LSNRCTL start to start Oracle prompt "Lsnrctl:command not found" [[Email Protected]_test etc]# Su oracle[[email protected]_test etc]$ lsnrctl startbash:lsnrctl:command not found#切换回root用户,