Database Administrator

Oracle SQL tuning procedure The full name of SQL is Structured Query Language (Structured Query Language ). SQL is an industrial standard database query language used in the middle of 1980s. Do not confuse SQL with commercial products such as

Redis for beginners (2) -- using Redis as the Mysql database cache, redismysql Two problems must be solved when Redis is used as the Mysql database cache. First, determine the data structure used to store data from Mysql. After determining the data

Oracle DBAs for IT ninja turtles are commonly used to query enumeration of vomiting blood, oracledba -1. query all objects in the systemSelect owner, object_name, object_type, created, last_ddl_time, timestamp, statusFrom dba_objectsWhere owner =

PL/SQL personal learning notes (2) and plsql personal learning notes IF condition DeclareCursor s is Select version from city_server t; S _ city_server.version % type; Begin Open s; Fetch s into s _; If s _> 2 Then DBMS_OUTPUT.put_line (s

Data Center reconstruction-view and Data Center reconstruction Views, stored procedures, triggers, and so on have long been heard, but they have never been really touched. They have been in a future State and cannot be escaped. What happened to Data

Why is it possible to log on to the oracle database as sysdba and enter your username and password ?, Sysdbaoracle This is actually a problem with oracle database authentication.In the sqlnet. ora fileSQLNET. AUTHENTICATION_SERVICES =

The listener. ora, sqlnet. ora, and tnsnames. ora configuration files are stored in the $ ORACLE_HOME \ network \ admin directory. 1. sqlnet. ora ----- is similar to the nsswitch. conf file of linux or other unix. It is used to determine how to find

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

Part 1: Check the Oracle database patch version 1. View All version information:Oracle@www.bkjia.com :~ /Product/11g/db/OPatch>./opatch lsinventoryInvoking OPatch 11.1.0.8.2 Oracle Interim Patch Installer version 11.1.0.8.2Copyright (c) 2010, Oracle

In addition to the tangle of queries, the rest are relatively simple! In fact, when I learned how to add, delete, modify, and query mongodb command lines, I also tried it one by one based on the examples on the official website, so please feel free

Recently, Sybase Central client (java client) was removed from IQ16.0. The new client may only use SCC ?! For old users, it is undoubtedly a pain point. It seems that only one client can be extracted from IQ15.4 or 15.3. In this case, I wrote a

Because both of them are used, informatica is easy to manage in the future, especially for data correction. when data is supplemented in the later stage, the data stream is clear at a glance.SQL is efficient, but it is inconvenient to maintain it

Change Password:1. For example, if your root user does not have a password and you want to change the password to 123456, the command is:Mysqladmin-u root password 1234562. If your root account has a password (123456), the command to change the

1. Preface As a saying goes, "You must know what it is, but you must know what it is ". But I don't know why. Why. This series of articles will show you how to do it and why it will also be involved. However, due to the limited level, the principle

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

For a system with massive data volumes, the performance bottleneck will eventually fall on the database. At this time, hardware upgrades and program optimization are powerless, A simple query may also impose a heavy burden on the database. Grid

What do you pay attention to when deleting data in a database? How to write code? Most of you can see these two problems. If you don't want to think about them, just use a Delete statement. Note that the deletion conditions should not be deleted.

Memory Database In traditional database tables, due to the limitation of the physical structure of disks, the structure of tables and indexes is B-Tree, which makes such indexes very weak in the highly concurrent OLTP environment, although there are

Database administrators must always pay close attention to potential database problems that may negatively affect the availability or performance of each system they manage. Generally, the database administrator can monitor and maintain the system

SQL Server has three different functions that can be used to obtain the final id value in the table containing the ID column: @ IDENTITY SCOPE_IDENTITY () IDENT_CURRENT ('Data table name') Although all the above three functions can return