Database Administrator

PuTTY + Xming for Oracle image Installation When we use PuTTY software to connect to a Linux server, ssh or telnet is used by default. Since PuTTY does not have the X window Function, the Oracle graphical installation interface cannot be

MySQL revokes an authorization Create test tableCreate table t1 (id int );Create table t2 (id int );Create table t3 (id int );Create table t4 (msg varchar (100 )); If the wildcard is used for authorization.Grant select, insert, update, delete on

Use undo in Oracle to restore Data [Note] when I accidentally saw a colleague's QQ message saying "really tired", I got a call from this colleague in less than 30 minutes, as shown below: When I was just doing data deletion, I found that the

Using filesort caused by order by optimization by MySQL Using filesort is generally used in the order by statement. Using filesort does not necessarily cause mysql performance problems. However, if the number of queries is very large, sorting in

How to Avoid synchronization of the MySQL database master Fault description: Go to the slave Database Mysql> show slave status \ G; The result is as follows: ... Slave_IO_Running: Yes Slave_ SQL _Running: No Last_errno.: 1062 ... Cause: 1. The

RedHat Linux 6.5 enterprise Redis 3.0.3 Installation System Environment preparation RedHat Linux 6.5 Enterprise Edition 1. Download Redis 3.0.3 Address: http://download.redis.io/releases/redis-3.0.3.tar.gz 2. decompress the file using the tar

In-depth explanation of batch row-column conversion in SQL, sqlbench Rotate rotate the table value expression by converting the unique value in a column of the expression to multiple columns in the output, and aggregate the values of any other

Error code: 1050 Table 'emp' already exists, empexists 1. Error description 1 queries executed, 0 success, 1 errors, 0 warnings query: create table emp (id int (8) primary key not null, ename varchar (20) not null, eage int (3), esex varchar (2)

Linux personal operation habits, linux personal habitsEdit ~ /. Add the following content to the bashrc file and define the alias #. bashrc # User specific aliases and functionsalias rm = 'rm-I 'alias cp = 'cp-I' alias mv = 'mv-I 'alias cls = 'clear'

ORA-00600: internal error code, arguments: [keltnfy-ldmInit], [46], [1], [], [], [], [], [], [], internalerrorcode SQL> startup nomount;ORA-00600: internal error code, arguments: [keltnfy-ldmInit], [46], [1], [], [], [], [], [] The root cause of

Leveldb learning: Cache and leveldb learning cache Leveldb implements the cache buffer substitution algorithm by itself. For details, see the code cache. h and cache. c files. In leveldb, table_cache is implemented based on class cache as the

The database-Related file View stored in FRA, frafile V $ controlfile; v $ logfile; v $ archived_log; v $ backup_piece; in the view above v $ datafile_copy, the value of the IS_RECOVERY_DEST_FILE column is YES, indicating ================ in FRA. ===

About connecting VBS to MySQL and Excel, vbsmysqlexcel Objective: To connect to MySQL and find data in the new Excel table Implementation process:1. Connect to the database First, go to the MySQL website to download an ODBC data source. After

[Data Center Charging System] project review and reconstruction prospects, data center Charging SystemAll the bugs that once forced you to think about hanging up, after completion, are just a few simple lines of code. Just like this impermanence of

Use bash to read and write csv file data to one of the scripts of MySQL database, Zookeeper Scenario:There is a csv file containing student details of multiple departments. You need to insert the file content into a data table to ensure that

Understanding and use of database connection pools and understanding of database connection pools1. What is a database connection pool? Official: the database Connection pool (Connection pooling) is a database Connection established when the program

Does tnsping prove that the Oracle database is available ?, TnspingoracleListener is a server-based network service of Oracle. It is mainly used to listen for connection requests from clients to database servers. Oracle officially defines it as: A

One accident caused by 0.6 billion data entries and one accident caused by 0.6 billionThe business staff told me that the IO of a System Disk lasted as high as 300 MB/s, and the system platform was AIX, so the topas check was indeed the case. Run

Rownum analysis, oraclerownum For the rownum problem in Oracle, many documents do not support>, >=, =, between... and. The preceding symbols can only be used (,> =, =, .. and will prompt SQL syntax errors, but often cannot find a record, and it

Detailed description of innobackupex Backup Recovery and innobackupex Backup Recovery I don't want to talk about anything that is useless. Let's look at the actual operation .. Let's just say, innobackupex reads locks for non-innodb tables during