Oracle

1. Simple Data Insertion Example-- Created on 2015/6/15 by LYH declare v_fnumber varchar2(10):=‘qwe‘; v_fname varchar2(10):=‘lyh‘; v_fage int:=10; v_fsalary int:=101.00;begin INSERT INTO t_employee(fnumber,fname,fage,fsalary)

The concept of locksLocks appear on data sharing occasions to ensure data consistency. When multiple sessions modify a table at the same time, the data needs to be locked accordingly.The lock has a read-only lock, exclusive lock "," shared exclusive

Methods for generating UUID in Oracle Download the Lofter client provides a function to generate the UUID in Oracle SQL sys_guid:http://download.oracle.com/docs/cd/e11882_01/

Set mydate=%date:~0,4%%date:~5,2%%date:~8,2%EXP username/Password @ instance name file=d:\mydata_%mydate%.dmp owner= user name Log=d:\mylog_%mydate%.logforfiles/p d:\123/s/M *.dmp/d -7/c "cmd/c del @path"DescriptionSet

Create a temporary table spaceCreate temporary tablespace test_tempTempfile ' E:\oracle\product\10.2.0\oradata\testserver\test_temp01.dbf 'Size 32mAutoextend onNext 32m MaxSize 2048mExtent management Local;Create a data table spaceCreate Tablespace

1. View All Users:SELECT * from Dba_users;SELECT * from All_users;SELECT * from User_users;2. View user or role system permissions (System permissions that are directly assigned to a user or role):SELECT * from Dba_sys_privs;SELECT * from

One,the characteristics of Oracle database, can have the following four points:1, the Complete data management function:The large amount of data, the persistence of data retention, the sharing of data, the reliability of data2, complete relations of

--Query field name, field type, field comment Select dd.*, EE. Constraint_type from (SELECT t.column_id, T.column_name, (case when (t.data_t YPE = ' VARCHAR2 ' OR t.data_type = ' RAW ' then T.data_type | | ' (' | | T.data_length | |

Query table structure　　SELECT t.column_id, t.column_name, (case when (t.data_type = ' VARCHAR2 ' OR t.data_type = ' RAW ') Then T.data_type | | ' (' | | T.data_length | | ') ' when (T.data_type = ' number '

?1. Error handlingOra-00911:invalid character . This is because the ";" is added at the end of the statement. For the sake of, remove the ";" SQL can execute the ~(This differs from SQL Server)?Oracle: Resolution of text-to-format string

SQL statement for querying and deleting duplicate records1, look for redundant records in the table, duplicate records are based on a single field (ID) to determineselect * FROM table where Id in (select ID from table group Byid have count (Id) > 1) 

Problems:1. Missing reference workaround, add Reference:   Using system;using system.collections.generic;using system.componentmodel;using system.data;using System.data.oracleclient;using system.drawing;using system.linq;using system.text;using

Startupalter. logspfile. ora SQL> select * from v $ version where rownum = 1; BANNER implements Oracle Database 11g Enterprise Edition Release 11.2.0.1.0-ProductionSQL>! Cat/etc/issueEnterprise Linux Enterprise Linux Server release 5.5 (Carthage)

Simulation and Analysis of librarycachepin problems in a single Oracle instance Simulation and Analysis of library cache pin problems with a single Oracle instance Local Environment: Oracle 10.2.0.5 x86-64bit for RHEL5.8 x86-64bit First

ENABLE_DDL_LOGGING initialization parameters for the new 11g feature ENABLE_DDL_LOGGING starts from 11g, but there are bugs in 11.2.0.2 and 11.1.0.7. This bug is described: Bug 12938609-ENABLE_DDL_LOGGING does not log RENAME table statements

Oracle elegant for loop insert inloopinsert Create table computers (comNo number (4) constraint PK_comp primary key, compModel varchar2 (64) constraint unique_comp unique, buyTime date, price number (12, 2) constraint ch_price check (price> 0 and

. Net connection to oracle Database --- ShinepansFAQ: 1. the reference solution is missing. Add reference: using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Data.OracleClient;using

Oracle cursor, process, and reference type 0. Common functions Substr (str, start, length); // reverse indexes can be performed. If length is not specified, it ends with to_number (str); // str to numberselect to_char (sysdate, 'yyyy-mm-dd hh24: mi:

Oracledblink causes too many remote database sessions The database of the on-site reporting network company could not be connected. I checked the database processes = 1500 and session = 2200 first. I think it is very big. Few people use this

Oracle copy column Value Requirement: Add a field to an existing table in the test environment, and manually add data to this column of some data in the table, now you want to add this field in the formal environment and copy the existing values in