Database Administrator

Method 1: offline tablespace 1. offline tablespace: alter tablespace tablespace_name offline;2. copy the data file to the new directory;3. rename: Modify the tablespace and control file;4. online tablespace; 1. offline tablespace zerone SQL> select

My newly installed Linux Mint 13 "Maya" Xfce RC, but because it is based on XUbuntu 12.04, it should be applicable to both XUbuntu and Ubuntu 12.04 1. Click here to download the installation media for Oracle express Oracle Database Express Edition 11

MySQL 5.6.7 RC was released a few days ago, so I decided to use tpcc-mysql to test its performance, including performance and stability. I can't say that my testing process is flawless because I found two bugs: MySQL 5.6.7 is locked during CREATE

First, I cannot directly log on to linux using Oracle on nomachine, so I created a simple user zc. This may also be the root cause of the following errors. Cat. bash_profile content: ######################################## ##### If [-f ~ /. Bashrc];

1. receive service requests A customer's dual-node RAC is not synchronized at two nodes. Ii. problem diagnosis 1. Check service status: Command crs_stat-t 2. Check time: the date node is two minutes faster than the second time of the node. 3. Check

Some Oracle users need to be granted the query permission for the dynamic performance view. The problems encountered today are as follows: SQL> conn/as sysdbaConnected.SQL> grant select on v $ session to hr;Grant select on v $ session to hr*ERROR

1. If the Key is null, the column value can be repeated, indicating that the column has no index or a non-leading column with a non-unique composite index. 2. If the Key is PRI, this column is an integral part of the primary Key. 3. If the Key is

On SQL server, it is easier to verify whether the data is Numeric. You can use the following methods: ISNUMERIC When it is a number type, the return value of the method is 1; otherwise, the return value is 0. Example: Select * from tablename

Deleting database tables from Oracle 10 Gb is not actually deleted, but stored in recyclebin. This process is similar to that of deleting files in windows and will be temporarily put into the recycle bin. The system will automatically rename the

You can CREATE synonyms in your own mode. This requires the create synonym system permission. If you want to CREATE a SYNONYM in another user's mode, you must have the create any synonym system permission. Synonyms created by common users are

I. Mysql Binlog format Introduction Mysql binlog has three formats: Statement, MiXED, and ROW! 1. Statement: Each SQL Statement that modifies data is recorded in the binlog. Advantage: you do not need to record changes in each row, which reduces the

I have been optimizing the SQL statements of various products recently, and I am also helping a colleague solve the deadlock problem. What I learned is that I have a deeper understanding of InnoDB locking. Let's take a look at this case today:

In some EBS projects that focus on permissions, common users usually do not have the System Administrator permission. Instead, the DBA can only add one role to one user. It is very troublesome to manually write a PLSQL script, keep the backup. since

I have created a test data table and want to test the difference between creating an index and not creating an index. The data volume of the created table is 108631962 rows. Insert 9999999 rows at a time, about half an hour at a time. It takes 37

A friend asked me this question today. If the record does not exist, a no data error will be prompted. The following is a solution to this problem on the Internet. When you execute SELECT… In PL_ SQL... INTO... If the returned result set is null,

In Oracle 11g installation, the following parameter values must be specified in linux. Select three of them as an example. The rest will not be written because they are not met for the time being.# Vim/etc/sysctl. conf Fs. aio-max-nr = 1048576Fs.

A few days ago when the machine room to connect to the database server, reported "ORA-12170: TNS: Connection timeout ". It took me two days to solve this error. Now, I hope you will not take any detours. The error message indicates that the local

When I shut down the server today, the database could not be shut down due to inexplicable reasons, so I had to use the Forced Command shutdown abort; but casually Oracle database could not open, always reported "ORA-03113: the "end" of the file in

--******************* -- CRS-0215 error handling --*******************   When installing Clusterware, Receive the following error message: The given interface (s), "eth0" is not public. Public interfaces shoshould be used to configure virtual

I have heard about the word trigger (first in the database video). After reading the video, I did not have a deep understanding of such things as triggers, stored procedures, and transactions, logs and so on are not checked in detail, and there is