Oracle

PHP ("PHP: Hypertext Preprocessor") is a widely used open source (Open Source)Source code) And can be embedded into the HTML multi-purpose scripting language. Its syntax is similar to C, Java, and Perl and is easy to learn. The main goal of this

If you need to reprint it, please indicate the source! (Thank you first ......) Configuration of Oracle TAF TAF is short for transparent application failover. Generally, the application TAF is in the OPS/RAC environment. The purpose and idea of

/* Step 2: create a temporary tablespace */Create temporary tablespace user_tempTempfile 'd: \ oracle \ oradata \ Oracle9i \ user_temp.dbf'Size 50 mAutoextend onNext 50 m maxsize 20480 mExtent management local; /* Step 2: create a data table space *

Sometimes it is unclear that all the values allowed for some parameters can be obtained by the following two methods:1. directly enter the error value and let the error promptCopy codeThe Code is as follows:SQL> alter system set "_

1. horizontal segmentation What is horizontal segmentation? In an image-like metaphor, there is only one window for dining in the canteen. The waiting queues are too long and all of them are in the S-type format. This makes it easy for the queuing

In layman's terms: The number of records connected by A left join B is the same as that of Table. The number of records connected by A right join B is the same as that of Table B. A left join B is equivalent to B right join   Table: Field_K, Field_A

SQL codeCopy codeThe Code is as follows:Create table test (a VARCHAR2 (20), B VARCHAR2 (20), c NUMBER, d VARCHAR2 (20 ))Insert into test VALUES ('a1', 'b1', 1, 'T ');Insert into test VALUES ('a3 ', 'b3', 3, 'T ');Insert into test VALUES ('a4 ', 'b4',

Delete an Oracle database in a Linux operating system in detail:1. Disable oracle server and background processesPs-ef | grep oraTurn off the databaseShutdown immediate2. Disable the listener.Lsnrctl statusIf it is enabled, execute lsnrctl stop to

1. control user access1. Create and modify user Creating UsersCreate/alter user new_user identified by password;Example: create user user_1 indentified by pwd_1Alter user user_1 identified by pwd_22. grant permissions to usersGrant privilege [,

This afternoon I conducted an experiment to add, modify, and delete columns in the test table. The procedure is as follows:Add a column:Alter table emp4 add test varchar2 (10 );Modify a column: Alter table emp4 modify test varchar2 (20 );Delete a

The ORACLE tutorial is the basics of Oracle PL/SQL language. PL/SQL is an extension of ORACLE's standard database language. ORACLE has integrated PL/SQL into ORACLE servers and other tools, in recent years, more developers and DBAs have started to

The ORACLE tutorial is: Renaming the foreign key of the Oracle system table. The Foreign keys in Oracle tables are the means to ensure the integrity of the system's reference, and the integrity of the Reference refers to the constraints that are

The ORACLE tutorial is: remote automatic backup of Oracle data in the database. In large commercial applications, Remote Disaster Recovery and backup of data are very important and necessary. Based on my practical experience, I have designed a

The ORACLE tutorial is: oracle date function. There are many date functions in oracle, For example: 1. add_months () is used to increase or decrease the date_value: = add_months (date_value, number_of_months) of some months from a date value.

The ORACLE tutorial is: how to directly run the OS command (below) in Oracle ). Exec SQL WHENEVER SQLERROR CONTINUE;Sqlglm (msg_buffer, & buffer_size, & msg_length );Printf ("Daemon error while connecting: \ n ");Printf ("%. * s \ n", msg_length,

The ORACLE tutorial is to use and maintain the Oracle password file. Summary: Oracle relational database system has been widely used for its excellent performance. Ensuring database security is an important part of database management. This article

The ORACLE tutorial is: Security Policy of Oracle Database. ---- Oracle is a relational database management system with powerful functions and excellent performance. It plays an important role in today's large database management systems. In the MIS

SQL statement for querying and deleting duplicate records1. Search for redundant duplicate records in the Table. duplicate records are determined based on a single field (peopleId ).Select * from peopleWhere peopleId in (select peopleId from people

Basic query:Copy codeThe Code is as follows:-- Query Information of all employeesSelect * from emp;-- Set the row widthSet linesize 120;-- Set the column width to the width of four digitsCol empno for 9999;-- Set the column width. a indicates the

1. Check whether SQL statements with lock tables exist.Copy codeThe Code is as follows:Select 'blocker ('| lb. sid |': '| sb. username |')-SQL: '| qb. SQL _text blockers,'Waiter ('| lw. sid |': '| sw. username |')-SQL: '| qw. SQL _text waitersFrom v