Database Administrator

Solution to Oracle temporary tablespace being too large There are two ways to solve the problem of temporary tablespace too much in Oracle. One is to increase the size of the temporary tablespace and the other is to create a temporary

Dangers of slow query in MySQL Databases 1. When a slow query occurs in a MySQL database, it is dangerous. Other DDL operations may cause the entire database to wait. It can be divided into the following situations: When a table is a MyiSAM table,

Resolving index failure when Oracle Partition Table deletes partition data I. Description Today, we have a small task to delete some data. Haha, please be happy first. Because the data table to be deleted is the partition table that I previously

Notes about MySQL Indexes Index In fact, the data in the database is stored by page.In fact, indexes are stored by page.Therefore, in essence, indexes also occupy hard disk space (in exchange for the greatest benefit with the minimum

Tutorial on installing Oracle 10 Gb database on Linux Oracle Database software can run on almost all Windows/Unix operating systems. It is recommended that you learn to use it because of the ease of access and open source of linux systems. (RedHat 5.

The structure of the Mysql table is InnoDB and data is restored from the ibd file. innodbibd The customer's machine system is shut down abnormally. After the restart, the mysql database cannot be started normally. After the system is reinstalled,

Switch between the primary and standby databases (physical standby databases) of DG and switch between dgSwitch between the master and slave databases of DGI. Sequence of opening and closing Databases Database opening sequence Start the

Oid is a hidden column of the system. Direct modification is not acceptable.Mysql = # update pg_class set oid = 99999 where oid = 73728;ERROR: cannot assign to system column "oid"LINE 1: update pg_class set oid = 99999 where oid = 73728; But we can

Table created. ID NAME---------------1 abc2 bc3 c SQL> select id, name from rev where name like '% bc ';ID NAME---------------1 abc2 bcExecution Plan----------------------------------------------------------Plan hash value: 3205185662 | Id |

8.3.5 Adding or Dropping Online Redo Log Files 8.3.5 add or delete the current redo log file Changing the size and number of the online redo log files is sometimes done to tune the database. you can add or drop online redo log file groups or members

My environment is like this: Win7 64-bit + Oracle 11g + PL/SQL 9.04 Since PL/SQL does not support 64-bit data at the moment, only Oracle client 32-bit data can be used, so you need to download it from the official website: Remember: you must

In Oracle tablespaces and data files, Temp tablespaces and files are special. In addition to the temporary segment (Temp segment) corresponding to the temp tablespace, it is automatically managed by Oracle. The sparse file feature is also an

Over the past few years, many companies have streamlined their IT departments. Many database administrators (DBAs) have to manage a large amount of SQL Server databases. What's worse is that there is often no real DBA, but you can find someone to

When I receive a credit card bill every month, I am always surprised and confused. How did I spend so much money last month? Looking at every bill, I couldn't remember where the money was spent. Think twice and take action. I want to keep an account.

Stored procedures are very powerful. To some extent, they can even replace the business logic layer. Next, we will illustrate using stored procedures to insert or update statements.1. Database Table Structure The database used is SQL Server2008.2.

When talking about Hadoop, we have to mention Lucene and Nutch. Lucene is not an application, but a pure Java high-performance full-text index engine toolkit. It can be easily embedded into various practical applications for full-text

1. Exp Optimization 1. Use the DIRECT and RECORDLENGTH options The DIRECT parameter defines whether to use DIRECT path (DIRECT = Y) or conventional path (DIRECT = N) for export ). Conventional path export uses the SQL SELECT statement to extract

Access data through views has obvious advantages. For example, data is kept confidential, data logic independence is ensured, and query operations are simplified. However, in other words, the views in the SQL Server database are not omnipotent, and

Users can pay attention to several common Oracle backup problems. First, backing up an Oracle database includes not only physical data backup (copies of database files ), it also includes Logical Data Backup-data export using SQL commands and

If multiple groups of duplicate PK Values exist in the table, it takes a lot of time to delete them one by one. In this case, you can use the following method: 1. First, run the group by query above to determine the number of repeated PK values and