Oracle

The parent-child relational record set or tree-like data record set is a common data organization form in software development. For example, the organizational structure in the office system, such as the province, city, and region in the user system,

1. ORA-12541: TNS: No listener Cause: the listener is not started or damaged. For the former, run the net start OracleOraHome81TNSListener command (the name may be different). For the latter, you can add a listener to "Listener Configuration" in the

Recently, many new Oracle beginners or those who upgraded from the old version of Oracle to 10 Gb asked questions about how to manually create a database in Oracle 10 Gb. Today, we are free to write down the whole process of manual database creation

After oracle9i is installed, enter the username, password, and host identifier to enter sal * plus. System/manager Sys/change_on_intall Scott/tiger Internal/oracle The above is the initial password The host string is null or @ + your service name.

1>. NUMBER Type Details:Oracle number datatype Syntax: NUMBER [(precision [, scale])]Short for: precision --> pScale --> s NUMBER (p, s)Range: 1 Data storage range:-1.0e-130 Saved in the machine range: 1 ~ 22 bytes Valid: the number of digits from

Problem: SQL> connect sys/password @ RAOASYS as sysdbaAlready connected to the idle routine.SQL> startupThe ORACLE routine has been started. Total System Global Area 109051904 bytesFixed Size 1295272 bytesVariable Size 92277848 bytesDatabase

UPDATE multiple tables in OracleThe following methods can be implemented:One is:Update table1Set (field1, field2. ..) =(Select Field1, field2 ....From table2Where table1.field1 = table2.field1)Where table1.field1 in (select field1 from table2) Two

When I read the Oracle performance optimization book, I talked about replacing in with exists and using table links to replace exists. About the former, the effect is generally obvious, and the exists efficiency is much higher than in, however, if

Because there are many ODU commands, especially the key unload commands, this article will briefly introduce the command sequence used for data recovery using ODU in several scenarios.Scenario 1: The database cannot be started, but the data

Create table testabc (A Number,B Date); Insert into testabc (a, B) values (1, TO_DATE (1-MAY-2010/, DD-MON-YYYY/HH24: MI ));Insert into testabc (a, B) values (1, TO_DATE (2-MAY-2010/, DD-MON-YYYY/HH24: MI ));Insert into testabc (a, B) values (1,

Exception in thread "main" java. lang. InternalError: Can't connect to X11 window server using '192. 168.3.10: 100' as the value of the DISPLAY variable.At sun. awt. X11GraphicsEnvironment. initDisplay (Native Method)At sun. awt.

Today, I received an email from the customer saying that the database had a lot of locks every day at last week. I collected AWR information from the customer and found that the top 5 ranked second was enq: TX-row lock contention.SQL> select SESSION_

In the use of Oracle hierarchical queries and with functions, everyone should have done something similar to department management. Generally, there will be another level-1 Department (sub-department) under the next department ), this level is

All about login Ming User-Managed Database Recovery Issuing set autorecovery on before issuing the RECOVER command. if you recovery with set autorecovery off, which is the default, then you must enter filenames manually or accept the suggested

Oracle USER management, authorization and backup I. USER Creation for authorization: the USER just created does not have any permissions to CREATE USER username indentife BY password authorization: GRANT permission 1, permission 2... TO User

Oracle cannot modify the data type of an existing column if there is data in the table. However, you can create a temporary column, copy the data of the column to the temporary column, delete the original column, and modify the name of the temporary

Summary of ORACLE Procedure Stored Procedure syntax subroutines and packages: subroutines are named PL/SQL blocks that can contain parameters and can be called at any time as needed. PL/SQL has two types of subprograms: process and function. A

Oracle database name: refers to the name of the oracle database, which uniquely identifies a database in a domain. The database name is specified by the db_name initialization parameter. The database name can contain up to 8 characters (numbers,

The first way to obtain the N records of a group in a database is Oracle: select * from(select row_number() over(partition by num order by num) gid,* from tb) tmp where gid=1； ROW_NUMBER()  Description: return the serial number of an expert in the

ORA-02097, ORA-00837 modify memory_target encountered a small problem today saw an ocp question a little doubt, did a small experiment, encountered two errors of ORA-02097, ORA-00837; the question is as follows: Q484. You set the following