Database Administrator

Today is. If you encounter a lib problem today, record it again. This is a case and a process of solving the problem. When we use sqlplus to log on to a unix database, problems such as: xxxxxx bad ELF interpreter: No such file or directory may occur.

According to the development feedback, the application will trigger an alarm at recently. The application log shows that the database connection pool is full and new connections are rejected. First, I made an ASH report (Report range: 7: 25 ~ ),

A decision tree is used to classify data for prediction. This decision tree method first forms a decision tree based on the training set data. If the tree cannot correctly classify all objects, select some exceptions and add them to the training set

Schema is the logical structure and feature description of all data in the database, also known as the conceptual mode or conceptual view. A view can be understood as a set of record values that the user or programmer sees and uses in the

I. HA FAILOVER: the technical basis for High Availability of Oracle RAC is Failover, which means that faults of a node in the hot river in the cluster will not affect user usage, the user who connects to the faulty node will be automatically

Update the new database from 32 to 64-bit 11G 11 2 0 3 An internal error occurs when an SQL statement is executed. Using PL/SQL DEVELOPER to query the execution opportunity of this statement triggers the ORA600

Database repair tools-only Access databases in *. mdb Format Introduction: There is a serious Bug in Access Database Operations. When the database file content increases, the file capacity increases. However, when the database content is deleted,

1. index creation Syntax:Create uniuqe | bitmap index . ON . (| ASC | DESC, | ASC | DESC ,...)TABLESPACE STORAGE LOGGING | NOLOGGINGCOMPUTE STATISTICSNOCOMPRESS | COMPRESS NOSORT | REVERSEPARTITION | global partition Description1) UNIQUE | BITMAP:

SQL Server paging query stored procedures used in the project. Stored Procedure] Create PROCEDURE prcPageResult-- Get data on a page -- @ CurrPage int = 1, -- current page number (that is, Top currPage) @ ShowColumn varchar (2000) = '*', -- the

Three words: strong, big, comprehensive, and strongly recommended SQL statement Query Result select (timestamp '2005-01-17 10:00' - timestamp '2005-01-01'); 16 10:10 select (timestamp '2005-01-17 10:00' -

When writing code today, because the business needs to be used in mybatis, it is bigger than the number, less than the number, so it is directly used in SQL.SELECT * FROM test WHERE 1 = 1 AND start_date = CURRENT_DATEHowever, an error is reported

Zookeeper This article describes the query statements. All examples are performed according to the following table. StuID StuName Age Sex 11090241031 Wang Xiaohu 21 Male 11090241032 Wang xiaoliu 22

Http://redis.io/ Official download: http://redis.io/download can download different versions as needed Https://github.com/mythz/redis-windows for windows Github resources can be downloaded by ZIP directly.   After the download is complete, perform

Scenario reproduction: The maintainer wants to use the plsql developer tool to view the data of a table a year ago. There are about rows of data in the table. Because there is no service at this time, the maintainer closes the application. When you

Description provided by SQL SERVER.Bit: an integer of 0 or 1Int: an integer from-2 ^ 31 (-2,147,483,648) to 2 ^ 31 (2,147,483,647)Smallint: integer number from-2 ^ 15 (-32,768) to 2 ^ 15 (32,767)Tinyint: integer number from 0 to 255Decimal: number

Like the session in. net, if you know the sessionID in the database, all operations will be known, because you have the unique identity. There are many things that can be done, such as: which user is doing what, what SQL is being executed, and how

Memory OLTP:Provides the memory OLTP function built into the core SQL Server database to significantly improve the transaction speed and throughput of database applications. The memory OLTP is installed with the SQL Server 2014 Engine. You do not

Various load file methods and time for MySQL and PostgreSQL are evaluated on virtual machines. Because it is the evaluation on the virtual machine, so the time is only for reference, don't be too real, just look at it.MySQL tool:1. built-in

 Data Source   Data sources have been used since contact with DBMS. One of the most important functions of DataSource is to manage Connection, which is often heard by ConnectionPool. Its management is to encapsulate the Connection obtained by

Example: update users set classes = '1' where id in ('u001', 'u002', 'u002', 'u002 '); update users set classes = '2' where id in ('u005 ', 'u006', 'u007 '); the users table content is as follows: + ------ + ----------- + ------------ + ------ + ----