Database Administrator

Oracle ADG Heartbeat failed to connect to standby fault case The customer's primary Database is a standalone Database of Oracle Database 11gR2 for AIX. The ibm hacmp software is deployed at the system level, the database is made into a master-slave

MySQL engine introduction ISAM, MyISAM, HEAP, InnoDB The MySQL Database Engine depends on how MySQL is compiled during installation. To add a new engine, you must recompile MySQL. By default, MySQL supports three engines: ISAM, MYISAM, and HEAP. The

Oracle: listener. ora, sqlnet. ora, tnsnames. ora configuration and example1. Solve the problem: TNS or the database cannot log on.The simplest and most effective method: use the tool netca provided by the Oracle System to configure (delete the

CentOS6.5x64 install 64-bit Oracle 11g in silent mode 1. Download the 64-bit Oracle11g source file and upload it to the Linux server. 2. Package installation check and installation: Install the tool using yum: Yum-y install binutils compat-libstdc ++

The correct method to restart MySQL in Linux: 1. MySQL installed through the rpm package Service mysqld restart 2. Install MySQL from the source code package // Linux Command to disable MySQL $ Mysql_dir/bin/mysqladmin-uroot-p shutdown // Linux

Python clears database error logs and python database logs # Coding = gbkFrom encodings import gbkImport reImport sysImport OSImport pyodbcImport tracebackImport decimal   # Connecting to a databaseConn = pyodbc. connect ('driver = {SQL Server};

Use MySQL Big Data Limit, mysql DATA limit Today, I am very surprised that the performance of the same function in MySQL varies by order of magnitude. First look at the unique id key index title of the ibmng (id, title, info) table. Let's take a

We also encountered the Oracle database sequence problem, so we can simply back up and restore the entire database. As follows: Imp/exp Method Table mode backup: Oracle @ sencloudServer: exp dhoffice/dhoffice rows = y indexes = n compress = n buffer

Transmission of Struts2 and jqGrid parameters, and transmission of struts2jqgrid Recently, jqGrid was used in the project to display data. However, I have never understood how data is transmitted. In jqGrid, The rowNum parameter defines how many

[Mysql] After windows is reinstalled, mysql and "Access denied for user 'root' @ 'IP'" are restored. mysqldenied Mysql databases are actually green software and can still be used after the system is reinstalled. 1. Reload the system and keep the

Vacuum full locks the table and is very inefficient. In practice, vacuum cannot be used to narrow down the pg_class, resulting in a long downtime.In fact, the simplest way to implement vacuum full is to copy a table again, create table B as select *

The SQLServer remote server does not exist. It is not specified as a valid Publishing Server, or you do not have permission to view available publishing servers. sqlserver does not exist. When a transaction release is created and an error occurs

1. All non-numeric characters for replacing a field are blankUpdate mobileNo_batchreg_black set mobile_no =Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace (Replace

MongoDB BASICS (9) sharding and mongodb Basics Sharding stores data on multiple servers. Mongodb uses sharding to support deployment of very large datasets and high throughput operations. The capabilities of a single server are limited in various

PostgreSQL tutorial (8): Index details, postgresql Index I. Index type: PostgreSQL provides multiple index types: B-Tree, Hash, GiST, and GIN. Because they use different algorithms, each index type has a suitable Query type, the create index Command

[DAO] simple document of billing system database design, dao Billing System DatabaseDatabase Design Documents Database Design Documents, SQL statements for table creation. 1) account Id number (9) PK account ID Login_name varchar2 (20) not null user

1. view the local node directory In the command window, enter db2 list node directory. 2. cataloguing a TCP/IP Node Command window: db2 catalog tcpip node Remote Server Ostype 3. Cancel node

A pivot table is a method for analyzing data. It contains a powerful data pivot function in Excel. What is data pivoting? It may be easier to give an example. Assume there is a data table: Sales volume of books ---------------------------------------

Use Cases I remember when I was tuning for a company, the person in charge sent me a bunch of business T-SQL scripts, I am still calm in the face of massive scripts, although I do not understand the internal complex business, however, we have to

If you deploy an Oracle database system on a Windows operating system, the startup process is written to the service list of the operating system. And some major services will be set to auto start. In this case, the database is automatically started