Oracle

Demand Oracle invokes third party external programs. Oracle uses SQLULDR2 to quickly export large amounts of data and then send messages with WinRAR compression. Source Java source Create or replace and compile Java source named

An example of this article describes Oracle data encryption methods. Share to everyone for your reference, specific as follows: Using MD5 encoding to encrypt database user password fields First, the preface As we all know, MD5 is currently the

For example, now there is a person table (table name: peosons)If you want to have the name, ID number, address of these three fields exactly the same records query Copy Code code as follows: Select p1.* From persons p1,persons P2

cascading queriesthere is a way to implement cascading queries in Oracle databases SELECT * //fields from table///To query with the child contact ID and the parent Contact ID's Table start with selfid=id ///Given a startid (field

The Oracle tutorial you are looking at is: Oracle performance optimization. Linux Journal published an article that optimizes the Oracle database and feels very useful. Briefly introduce its summary and everyone to share Linux in enterprise database

The examples in this article describe the use of Oracle triggers. Share to everyone for your reference, specific as follows: Introduction of Triggers The definition of a trigger is that when a condition is set up, the statement defined within the

A foreign key specifies that the value of a column (or a group of columns) must conform to the values of some rows in another table. We say this is to maintain the referential integrity of the associated table.In the graphical interface, the Foreign

1. Visit the official website of oralce, download the related compression packageHttp://www.oracle.com/technetwork/topics/intel-macsoft-096467.html Note: Under the Mac mountain lion operating system, download the x86 32-bit version. Can't use

The Oracle tutorial is looking at the power of multiple CPUs with Oracle parallel queries. Parameters Let's take a closer look at how the number of CPUs affects these parameters. Parameter Fast_start_parallel_rollback One exciting thing about

//-------------------------------- Work functions //-------------------------------- Reading Records Primary work function, reading the corresponding record from the table according to the conditions given The return value is a two-dimensional

basic syntax and examples:1, EXP:There are three main ways (complete, user, table)1. Complete:EXP System/manager buffer=64000 file=c:\full. DMP full=yIf you want to perform a full export, you must have special permissions2, User mode:EXP sonic/sonic

The following information is from the Internet, posted a save for later use, one for everyone to share. Character function--returns the character value These functions all receive the arguments of the character family type (except CHR) and return

Get table field: SELECT * from user_tab_columns where table_name= ' user table ' ORDER by column_name Get Table Comments: SELECT * from user_tab_comments where table_name= ' user table ' ORDER BY table_name Get field Comments:

Millisecond conversion to date SELECT To_char (1406538765000/1000) + to_date (' 1970-01-01 08:00:00 ', ' yyyy-mm-dd HH:MI:SS '), ' yyyy-mm -dd HH24:MI:SS ') as CDATE from DUAL; Date conversion milliseconds SELECT To_number (to_date ('

Problem: In the SQL Server database, it is also convenient to use the field properties of the self added column. And in Oracle, there is no such function, how to achieve it? A: Although there are no trigger in Oracle, they can be implemented by

(1) oracleservicesid Database service, which automatically starts and stops the database. If a database is installed, its default startup type is automatic. The service process is ORACLE.EXE, parameter file initsid.ora, log file SIDALRT.log,

Here's the solution: 1-from the command prompt, stop isqlplus:C:\>isqlplusctl stop 2-assuming that you install Oracle under C Drive, run the following comands: C:\>set oracle_home=c:\oracle\product\10.2.0\db_1 C:\>set JAVA_HOME=%ORACLE_HOME%\JDK

Meaning explanation:Decode (condition, value 1, return value 1, value 2, return value 2,... Value N, return value N, default value) The meaning of the function is as follows: Copy Code code as follows: IF condition = value 1 THEN

(1) View character set (three is equivalent) Copy Code code as follows: SELECT * from v$nls_parameters where parameter= ' Nls_characterset ' SELECT * from nls_database_parameters where parameter= ' Nls_characterset ' SELECT * from

Type Meaning Storage description Note CHAR Fixed-length strings Max length 2000bytes 　 VARCHAR2 Variable-length strings , Max length 4000bytes Maximum length of the index can be 749