Database Administrator

Create a log file in Oracle The syntax for creating a log file in Oracle is as follows: Alter database database_name add logfile [group group_number] (File_name [, file_name [,...]) [SIZE number] [reuse];The syntax is described as follows;Group

How to forget the MySQL root Password in Windows 1. Open the MySQL configuration file my. ini and add skip-grant-tables to the end of the file or add it to the [mysqld. 2. Restart the MYSQL service. In windows:Net stop MySQLNet start MySQL If an

MongoDB Study Notes (2)-basic connection example between Node. js and MongoDBPrerequisites Node. js and MongoDB have been installed. The node. js used in this article is v0.12.0 and MongoDB is 3.0.0. MongoDB Study Notes (1)-install MongoDB on

Insert statement, @ IDENTITY, @ rowcount, rowcount For the table structure in this instance, see the document "Create a table, insert an id column, and automatically generate an id ". Use yuyongTest Insert into student (name, info) Values (

IOT database requirements and current technical analysis Iot is currently the most promising technology trend. By 2020, the world will have 20 billion-200 billion Iot devices (Gartner predicted 26 billion, ABI predicted 30 billion, Oracle predicted 5

Data splitting-create a Mysql Partition Table and perform performance analysis to split mysql For how to install Mysql, refer: Http://blog.csdn.net/jhq0113/article/details/43812895 For more information about Mysql partition tables, see: Http://blog.

Study database notes 6. Database notes I Summarized some problem-solving templates, which can be applied in some cases Model 1 group by + statistical function combinationExampleCalculate the number of items under each topicSelct cat_id, count (*)

Authorization for CONNECT, RESOURCE, and DBA in ORACLE, oracledba CONNECT, RESOURCE, and DBA are the three built-in roles of the ORACLE system. The role permissions are as follows: CONNECT: users with the Connect permission can only log on to

DataTable add data, datatable add DataTable dt = new DataTable ("cart "); DataColumn dc1 = new DataColumn ("prizename", Type. GetType ("System. String ")); DataColumn dc2 = new DataColumn ("point", Type. GetType ("System. Int16 ")); DataColumn

Message interaction process between C language programs and databases in non-direct connection mode, and language program process Abstr] In "how to execute SQL statements in C language?" (Http://www.zhouzhaoxiong.com/116.html) in the article, I

Preliminary understanding of BI-SSIS and BI-SSIS In the previous article, I briefly introduced the overall framework of BI. In the next few articles, I will briefly explain some knowledge points. First, we will go to SSIS learning.1. What is

Basic SQL internal connection and external connection, basic SQL connection Some problems have been depressing for a long time. For example, why is there a connection between the left and right sides? If the foreign key is empty, the foreign key

Explanation of database paradigm and explanation of database paradigm Database paradigm 1NF 2NF 3NF BCNF (example) The design paradigm (paradigm, database design paradigm, and database design paradigm) is a set of relational patterns at a certain

Ubuntu14.04LTS64-bit installation of Oracle11g and oracle11g Oracle does not officially state that it supports ubuntu installation. Therefore, the environment must be adjusted and prepared before installation can be successful. Ps, I tried multiple

ServiceStack. Redis -- Redis client solution on. net, servicestack. redisServiceStack. Redis -- Redis client solution on. net  Source code and usage: Https://github.com/ServiceStack/ServiceStack.Redis  Example:

Oracle 12c 3 pdb pluggable test, 12 cpdb DECLAREl_result BOOLEAN; BEGINl_result: = partition (pdb_descr_file => '/u02/pdb/pdb3.xml', pdb_name => 'pdb3'); IF l_result THENDBMS_OUTPUT.PUT_LINE ('compuble '); ELSEDBMS_OUTPUT.PUT_LINE ('compatible ');

Oracle 12c learning 3 converting nocdb to pdb and nocdbpdb 01:23:06 sys @ orcl> select name, decode (cdb, 'yes', 'multitenant Option enabled', 'regular 12c Database: ') "Multitenant Option", open_mode, con_id from v $ database; NAME Multitenant

14. Search Overview and sequential search, and 14 Search Overview order1. Search Overview1. Search:That is, a data element (or record) whose keyword is equal to the given value is determined in the search table based on a given value ). If the table

Group by, improve SQL running speed, groupsql Data Table dh_order_detail contains a total of 169247 data records. Original SQL SELECTFROM_UNIXTIME (order_time, '% H: % I') 'time', city, district, LEFT (company, 6) company, goods_num,

Add not null constraint and constraint lenotnull constraint to oracleWhen creating a table, add the not null constraint to the column in the following format:Column_name data_type[Constraint constraint_name] not nullConstraint constraint_name