Oracle

1. Create dblink for Oracle databases in SQL Server as you would for Oracle databasesSecurity is also defined (seemingly no need to follow the access string only need to fill in one)Direct query error, need to change registry add optionkey 1 ,

Second, materialized view(a) What is materialized viewA view is a virtual table (which can also be considered a statement), based on the result set returned by the query statement that was specified when it was created. Each access to it causes this

Meaning explanation:Decode (condition, value 1, return value 1, value 2, return value 2,... ) Value N, return value N, default value)The function has the following meanings:IF condition = value 1 Thenreturn value 1ELSEIF condition = value 2

Third, stored procedures(a) What is a stored procedureA stored procedure is a named PL/SQL block that is stored in a database and is a database object. The application can invoke the stored procedure and execute the appropriate logic.Both stored

Case-when usage, simple case functionA simple case expression that determines the return value using an expression.Grammar:Case Search_expressionWhen Expression1 then RESULT1When Expression2 then RESULT2...When Expressionn then RESULTNELSE

The author of the company recently on a system, the system uses middleware to connect to the Oracle database, after a period of time the system will stop responding. The problem is found in 2 points:1. After the middleware thread has executed the

First, decode functionMeaning explanation:1, Decode (condition, value 1, return value 1, value 2, return value 2,... Value N, return value N, default value)The function has the following meanings:IF condition = value 1 ThenRETURN (translation value 1

DDL operationsHow to set user permissions in WindowsData Types for OracleCtrl-click the table name to manipulate the mouseThe inserted data needs to be checked to create the tableMain Table Clazz Delete data from the table setting cascade will also

1. Create a userSu-rootGroupadd OinstallGroupadd dbaUSERADD-G oinstall-g dba-m OracleCentos7ADDUSER-G oinstall-g dba-m Oraclepasswd Oracle2. Configure X11Whether to install the X Window SystemUse Rpm-qa |grep-i x11Installation is not

1. View archived InformationSQL>log listDatabaselog mode No Archive modeautomatic Archival disabledarchive destination log sequence 244 Current log sequence 246The current database is not open for

I. Preparation TOOLS1.Oracle database: Full name Oracle Datebase is a relational database management system of Oracle Corporation;2.pl/sql:pl/sql Developer is an integrated development environment specifically for the development of Oracle database

One, concurrencyConcurrency is the most important feature of an OLTP database, but concurrency involves the acquisition, sharing, and locking of resources.Mysql:MySQL is a table-level lock-based, the granularity of the resource lock is very large,

Today in order to modify the database configuration, the sga_max_size set to 20G, but Sga_target did not change, still for 10G results after the restart of the database will not start, reported ORA-00821 error ora-00821:specified value of Sga_target

There is a need in the work, now there are some data in the new table is the same as the basic cousin, so that only need to move the data in the cousin to the new table can be, while the different fields to modify the data can be modified in the

1. INDEX RANGE SCAN--Please remember this index RANGE scan scanning methoddrop table T Purge;CREATE TABLE T as select * from Dba_objects;Update T set object_id=rownum;CommitCREATE index idx_object_id on T (object_id);Set Autotrace traceonlySet

First, what is the waterline (high water Mark)?All Oracle segments (segments, where, for ease of understanding, suggest segment as a synonym for a table) have a limit on the amount of data that can be accommodated in a paragraph, we call this cap

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PLM project has been formally tested in-line, data management is the most serious, easy to recover processing, to avoid data loss. Idea: Data export + timed backup + data cycle cleanup1, copy the Oracle installation directory Bin Exp.exe (can also

SELECT DISTINCT AB. TABLE_NAME,Ab. Segment_name,Ab. Tablespace_name,Ab. OWNER,Sum (AC. bytes/1024/1024/1024) GBFrom Dba_lobs AB, dba_segments ACwhere AB. OWNER in (SELECT USERNAMEFrom Dba_users AWHERE a.account_status = ' OPEN 'and

The company used to use DMP Operation data import and export, recently from other places people to be SQL file database files, have to learn how to import large files of SQL, good response to various emergencies.1, first you will use Sqlplus to