Oracle

--View the lock table process SQL statement 1:SELECT Sess.sid, sess.serial#, lo.oracle_username, lo.os_user_name, ao. object_name , lo.locked_mode fromWHERE ao. object_id= lo. object_id and = Sess.sid;OrSELECT

substr intercept FieldSUBSTR (string, intercept start position, intercept length)SUBSTR (STR,N,M)Second, the three parameters can be omitted,The second parameter is a negative number, which means to intercept m from the nth bit of the

First, connect the database1, start Sql*plus, but do not log insqlplus/nolog 2. Connect to Oracle with SYSDBA role Connect Username/password as Sysdba (provided the user has SYSDBA privileges)3, direct connection with the SYS user l

The Variance function variance (x),The specific methods are:The variance s,a is the average of X1,X2...XN,then S = [(x1-a) ^2+ (x2-a) ^2+ (x3-a) ^2+ ... (xn-a) ^2]/nStandard deviation function StdDev (x),The specific algorithm is:The variance is

Common scenario: When backing up an Oracle database from the server and restoring the Oracle database on the local machine, you often encounter inconsistent database character encoding, and can use the following command to change the local Oracle

4.oracle database Start-up processWindows operating systemStart monitoring: Lsnrctl start;Start DB instance: oradim-startup-sid Instance NameLinux SystemsStart monitoring: Lsnrctl start;Launch DB instance: Sqlplus Sys/change_on_install as

One, the Oracle General function VNL (A, A, a, b) for any type, if the value of a is NOT NULL returns the value of a, otherwise returns the value ofConditional judgment can be used in OracleCase FieldWhen condition 1 then expression 1When condition 2

There are four types of SQL statements:Data definition language (DDL)Data manipulation Language (DML)Data Control Language (DCL)Transaction Control Language (TCL)Data Definition Language (DDL)DDL gives us the ability to create or delete tables. You

---- First step: Set up empty table export----The empty table cannot be exported because Oracle 11G is exported with export. The workaround is as follows: (There is a new feature in 11G that does not allocate segment to save space when the table has

http://blog.csdn.net/cselmu9/article/details/8070728/Due to the continuous updating of hardware technology, Win7 system gradually become mainstream, and computer memory gradually increased, in order to make full use of memory resources (because 32

CREATE TABLE SpaceCreate Tablespace AchartsDataFile ' D:\oradata\orcl\ACHARTS01. DBF ' size 800mAutoextend on next 10m maxsize 3000mDelete Table spaceDrop Tablespace AchartsCreate user "" is passwordCreate user Acharts identified by "Acharts";Delete

Note: A statement that is not executed every time is logged (if the executed statement is found in the table, Oracle does not record again, meaning that the statement executed this time is identical to the last or previous statement, and the

-- Check the job's next execution time and time intervalSELECT * from dba_jobs where job = ' 774 ';-- Start JobEXEC Dbms_job.run (774);--Deactivate jobEXEC Dbms_job. Broken (job#,true);EXEC Dbms_job. Broken (774, TRUE);--See how many job executions

I. Using a FOR loop cursor: Traverse all positions as manager's employees1. Define a cursor (a cursor is a small collection)2. Defining cursor Variables3. Using a For loop cursorDeclare --Define cursor c_job cursor c_job is select Empno, ename,

1.Oracle Download InstantclientUnzip to D:\zl\instantclient_11_22. Configure Environment variables Oracle_home = D:\zl\instantclient_11_2 Tns_admin = D:\zl\instantclient_11_2 Nls_lang = Simplified Chinese_china. Zhs16gbk 3.

First, create a user:Login with system administrator, right click on uers to create new,General: The default space is selected by users, temp table space is selected for temporary tablespace, and profile selection is default.Object permissions: Do

Operating system: Windows system we can use the task plan to achieve, for the WinXP system, set the steps below, start---setup---Control Panel---Task schedule, and then add the task schedule, follow the wizard to complete the configuration; For the

Database objects: Tables, views, indexes, sequences, synonyms, stored procedures, stored functionsStored procedure: Refers to a subroutine stored in the database for all user programs called stored procedures, storage functionsSame point for stored

Folder structureInit script|----orcl_sql|----init_user.sql|----tab_home.sql |----Tab_user.sql |----init.batInit.bat@echo Off@echo---------------------------------------------------------------------@echo ^| ^| @echo ^|

1,Oracle's parser according to right-to-left order the table name in the FROM clause is processed, so that the last table written in the FROM clause (the underlying table, driving tables) will be processed first . In the case that the FROM clause