Oracle

The bfile type is a lob type, and the bfile type is just a pointer to the previous file on the operating system to provide read-only access to the operating system files. Maintenance outside the database, not part of the database.When using BFILE,

first, what is a view. 1, the view is a kind of virtual table;2, the view is based on the existing table , the view to the establishment of these tables is called the base table ;3. The statement that provides the data content to the view is a

First ask the table space name and size of the other database, then create the appropriate tablespace in your Oracle, and finally use the command to import and export the data.Add:1. To create a new database;Oracle data import and export imp/exp is

Sometimes you want to force the deletion of an already connected Oracle user, cannot be deleted directly, can use kill session information. For example, to delete a connected SDE user today, you can delete a "connecting" user in the following ways. 1

For the sake of convenience, the following simple models are established and some test data are constructed:In a business admissibility subsystem BSS,SQL Code1 --Customer Information Sheet2 Create TableCustomers3 (4customer_id Number(8) not

Oracle stored procedure Returns a result set that requires a cursor as a stored procedure parameter1. Create PakageCREATE OR REPLACE Package pkg_query as TYPE cur_query is REF CURSOR; END Pkg_query;2. Create a stored procedure ()Create or Replace

When using exp, you need to be aware of the following pointswhen the previous client version, the version of the target client, Note that you need to set the CharSet, which is Nls_langReference settings for the Oracle character setNls_lang The

When using Oracle for paged queries, we usually carry a lot of parameters. But today we found a very strange thing. When the sort field is not a primary key and the values of the sorted field are the same in multiple data, the sort order of the

Oracle is not valid and is not re-validatedThe code is as follows:SQL Codeas follows: --创建中国地图表create table  china_address(       id number not null primary key,       address_name varchar2(30) not null,       parent_address_id number , 

Oracle modifies table space sizeAfter the database was established using ORACLE10G, some data was imported into the database and an error occurred the next day when the data table was imported to the database:It's a lot of data. The reason why the

Create a table to build a table statement:CREATETABLESc_district (IDNumber (10)NotNull, parent_idNumber (10), NAMEVARCHAR2 (255 BYTE)Notnull); alter table sc_district addconstraint SC_DISTRICT_PK primary key (ID)); alter table sc_district

这两天啊有一个心的业务，是需要如果我批量修改数据的话，那么另一张表的数据也需要修改，也是多条的修改，发现这个问题的时候，自然而然的想到了触发器，但是以前都是简单的单条语句的跟新，没有过整个表的去做一个触发器，今天学习了一下数据库中的循环，这里写一下。 在写触发器的时候用到了一个循环和一个Cursor，触发器如下：create OR replace trigger trg_test before update on cm_bogie_inandoutreport

Long time no blog, in the study of Oracle has already learned MySQL, thought in learning Oracle should be a lot easier, but, I think wrong, Oracle is more difficult than MySQL on a level, mainly in the following areas to send:1:oracle's authority

Description of stored procedure and stored function: Store function has return value! The stored procedure does not return a value!A subroutine stored in a database that is called by all user programs is called a stored procedure, stored

--Delete the original table: Drop table emp;--CREATE table empcreate table emp ( deptno number, ename varchar2 (), Sal number );-- Insert data--Department 1 Employee information INSERT into EMP values (1, ' King Hee 1 ', 15000); INSERT

Today we need to count the number of rows for all the tables under the specified user, and then use the Oracle built-in view:Select Table_name,num_rows from dba_tables where owner = ' USERNAME '; or select Table_name,num_rows from

Oracle 12541,12560,00511 no listener, protocol adapter error problem analysis and solutionProblem Description:1. Lsnrctl start, stop, very slow, the emergence of the phenomenon of Dayton; 2. Details of execution lsnrctl are as follows----------------

Let's take a look at what jumbo frames is.We know that in the TCP/IP covariance cluster, the Ethernet Data Link layer communicates in frames (frame), the size of 1 frames is set to 1,518 bytes, the MTU of the traditional 10M nic frame (Maximum

In an Oracle database, you can use the Wm_concat (column) function to merge fields, and the following is a detailed introduction to the implementation of this feature for your reference.The Oracle Wm_concat (column) function allows us to use it

To prevent users from concurrently accessing and modifying resources at the same time, Oracle uses different types of locks to control concurrent access to data to prevent disruptive interactions between users1, Lock tablecommon syntax for locking