Database Administrator

Oracle uses regular expressions for four main functions Oracle Regular Expression functions: regexp_like, regexp_substr, regexp_instr, regexp_replace Oracle uses regular expressions for four main functions: 1. regexp_like can only be used for

Oracle control file multiplexing 1. Oracle control file multiplexing 1. show parameter control-- View Control File InformationShow parameter spfile-- Check whether spfile exists.Create pfile from spfile;-- Generate pfileShutdown immediate-- Close

Oracle left Outer Join tests For more in-depth left outer join, we did some tests. There are several forms of external join writing. We can track the final SQL conversion form through 10053. -- Initialize data Create table (Id number,Age

Oracle index management After the database has been running for a period of time, due to frequent addition, deletion, and modification, the index will produce fragments, and the query efficiency will naturally be affected when the fragmentation

MySQL string Truncation MySQL string Truncation 1. Extract strings from the leftLeft (str, length)Note: left (truncated field, truncated length)Example: select left (content, 200) as abstract from my_content_t 2. Extract strings from the rightRight (

Oracle 11 GB backup and recovery example of using RMAN to create backup Sets Oracle 11 GB backup and recovery example of using RMAN to create backup Sets -- % D: Specifies the name of the database -- % S: Specifies the backup set number. This number

Binlog Processing Method for MySQL DATA Recently, the disk has grown very fast and it is found that binlog logs occupy a large amount of disk resources. We use manual cleanup, and set Automatic cleanup later. View the specified deletion log Mysql>

The Oracle 11g empty table cannot be exported. The deferred_segment_creation parameter is added to the Oracle 11g. The default value is true when the database is created. This parameter means delayed loading. When no data exists in the table, no

ORA-13600 QSM-00794 error Solution 1, wanted to use dbms_advisor to do a SQL access advisor test, but unexpectedly encountered ORA-13600 QSM-00794 error, as follows: SQL> DECLARE2 task_name VARCHAR2 (200 );3 BEGIN4 task_name: = 'my _ task ';

Oracle 10 Gb database creation and remote access configuration Recently, Oracle was used in the project, with oracle10gb. because many people in the group use the database, and the oracle database occupies a lot of memory, it is placed on a separate

Oracle Database listening is very slow, and hang basically handles faults Tester email feedback:The connection to the database to be ordered is very slow, or even cannot be connected. I want to check it. View:Oracle @ wdatest11 :~

Use SQL statements to add an auto-incrementing primary key or delete a primary key or an SQL primary key to a table. When I first met this requirement, I searched the internet and found that I couldn't do it. I had to delete the primary key column

QlikView charts show year-on-year data, and qlikview charts show year-on-year data. Data preparation is as follows: SalesData:LOADNum(ID) as ID,Date(Date) as Date,Month,Num(Year) as Year,Num(Sales) as SalesInline [ID, Date, Month, Year, Sales1, 2012-

Detailed process of manually adding a tablespace In the RAC environment, and manually adding a tablespace In the rac Environment ######################################## ###################### Detailed process of manually adding a tablespace In the

Database learning experience and learning experienceDatabase learning experience is a new concept for us. Of course, the premise is that before we learn it, the first impression of this course is very abstract, it should be difficult and tiring to

High aggregation, low coupling, and low coupling This is a concept in software engineering. First, you must know that a software is composed of multiple subprograms, and a program is composed of multiple modules (methods! Cohesion refers to the

SQL Server is the storage process for code reduction, and SQL reduction The stored procedure can be used to improve the database query efficiency because it has been compiled in advance and stored in the memory. It is very efficient because it does

Application of Oracle virtual index, oracle virtual Index When performing SQL optimization, you may need to add an index to test whether it can help improve the performance. If the table is very large at this time, it will be very troublesome to

Sqlite learning notes 9: Using sqlite to insert data in C language, sqlite learning notes I have created a table before. Now I want to insert some data into the table. The data inserted is similar to that in the table creation. The SQL language is

The first introduction to Data Structures Based on previous experience, I found that reading a book, if I read a book a day or a day, I read a little at the end, so these days I decided to take a shot and read the book "Introduction to Data