Database Administrator

Bkjia.com exclusive Article] In fact, it is not complicated to delete the data in the database. Why should I do this? First, I will introduce how to delete all the data in the database, because the data may form a constrained relationship between

According to the definition of NULL, NULL indicates unknown. Therefore, the results of two NULL comparisons are neither equal nor unequal, and the results are still unknown. According to this definition, the existence of multiple NULL values should

I. Original development intention I believe that when you write SQL statements at ordinary times, in order to save time, you do not like to put the pointer ON THE Shift key to play the keyword in the upper case, such as creating a database, directly

BKJIA database channel recommends "SQL Server beginners to proficient" and "database index and query topics" to help you. Today, the product department needs to export batch data, but several tables that need to be connected for query and query are

In the past, I was often confused by the user name and login name in SQL Server, because I used the sa Login Name to fix everything. Of course, this would pose some security risks. The online articles seem to be very good, but still do not

We have analyzed the Infobright architecture and briefly introduced the compression process and working principle of Infobright. Now we will discuss the issue of query optimization. 1) configure the environment In Linux, you can configure the

Psql is a powerful query and script tool provided by PostgreSQL. This article will introduce you to the introduction of this tool. I. psql Psql is a query tool provided by PostgreSQL. That is to say, it is available on any operating system

If you are running a Web application that uses MySQL, it can store passwords or other sensitive information in the application. Protecting this data from access by hackers or prophers is an important concern, because you cannot allow unauthorized

The first method is to install mysql ODBC and use the export function of SQL server to select the mysql data source for direct data export. This method is simple, but there are many drawbacks for practical applications, the most important

What is MMDBMS? The master database system (MMDB) manages the entire database or a part of the database in the master database, so you can directly access the data without accessing the disk, so that the master database has a high-performance

Introduction Both DBAs and developers like indexing. They can accelerate query and search, especially in a data warehouse environment, because the database will receive many ad-hoc requests. To avoid full table search, we usually create an index in

The Flash query function introduced by Oracle 9i displays the query results of the previous time point. However, the table itself has not changed. Oracle 10 Gb enhanced the flashback function to permanently flash back a table. Now, Oracle 10g

Before Oracle9i, although there was a NEW_TIME function that could change the timestamp of DATE, there was no data type specifically used to store time zone information. In Oracle9i, we can use the DBTIMEZONE pseudo field to query the time zone of

We need to inform our storage team of the I/O requirements required to implement Oracle 11i. However, we are confused about choosing 6 k I/O or 8 k I/O. Our database size is 1.6 TB and there are about 1200 concurrent users. What is the best way to

SQL _PLUS, spool ExecCompProc.sql select 'alter procedure '||object_name||' compile;' From all_objects where status = 'INVALID' and object_type = 'PROCEDURE'; spool off @ExecCompProc.Sql;  Organize into a stored procedure

If you want to transfer a large amount of data in Oracle (more than 80 Mb) to another user and another tablespace. You can use the following method to quickly transfer data. I. How to create a new table Create table target_tablename

Abstr 24*7 is also named 24*7*365). More and more high-availability systems are being widely applied, because in the actual environment, the uninterrupted system represents the uninterrupted obligation income. However ◆ How to build and manage a 24*7

In SQL Server 2005, another powerful new feature is database snapshots. A database snapshot is a read-only copy of a database. It is the ing of all data in the database, and its content is determined by the time when the snapshot is executed. These

Introduced by Chen Min's blog] MySQL is increasingly used in database applications due to its small size and efficient operations. When I was developing a P2P application, I used MySQL to store P2P nodes. Because P2P applications have tens of

Introduction Every program using a relational database may encounter data deadlocks or unavailability, which need to be programmed in the Code; this article mainly introduces the retry logic concepts related to Database Transaction deadlocks and