Database Administrator

Blob Field1. The content field with the premise id = 316083730656 has a valueUpdate docs set content = Empty_Blob ()Where id DeclareSrc_Blob;V_Blob Blob;Amount Binary_Integer;Offset Integer;Cursor testCursor isSelect contentFrom docsWhere id <> 3160

Redo Log BufferThe size is determined by the initialization parameters.LOG_BUFFERThe default value of this parameter isMax (512KB, 128KB * CPU_COUNT). Generally, this default value is sufficient,WeYes, the Redo Log BufferWrite operations are quite

The Oracle database update was used a few days ago, but there were a lot of problems with this simple problem. Therefore, we will search online materials and summarize them here for temporary use. The SQL statements listed below are based on the

Linux This method should be the quickest way to solve Chinese Garbled text. You do not need to change the mysql encoding, but only use it in linux: 1. In the main function of main. cpp of the QT program, the three sentences of QTextCodec ''' are as

SMON is short for System Monitor. If the Oracle instance fails, any data in SGA that is not written to the disk will be lost. In many cases, Oracle instances may fail. For example, an operating system crash may cause Oracle instances to fail. When

When I was working on a project today, a problem occurred while inserting data into the table. The database reported a violation of the unique constraint and the solution was simple: The project uses the Oracle database. In the early stage, I

Recently, Oracle 11gR1 was installed on Fedora 14. The database can be normally connected from the local machine, but the connection cannot be established from other hosts.Later I found it was the reason for the firewall. First, run the following

We all know that date and timestamp are both expressions of date and time, but the two types of precision are different. The former is accurate to seconds, and the latter is precise to decimal seconds (fractional_seconds_precision ), it can be 0 to 9

The default character encoding of mysql is latin1, while I use UTF-8, and it becomes ????? The solution is as follows: 1. In windows: Modify the my. ini file. Change default-character-set = latin1 to default-character-set = utf8 to restart.2. in

Several major Oracle background processes System Monitor SMON restores an instance after it crashes, merges free space in the database, and manages the space for classified operations Process Monitor PMON cleans up faulty user database

Note: 1. If the following parameters are set incorrectly, the Folder cannot be properly displayed, and automatic formatting is not allowed. All settings are displayed. For example, Form-level triggers: WHEN-NEW-FORM-INSTANCE beginFDRCSID ('$ Header:

Recently, when performing some partition operations in Oracle, the global index of some partition tables is always invalid. Therefore, perform a detailed test on the related operations. The following is a summary of my test results: ADD partition,

I. B-Tree indexes 1. Principles for selecting index fields: The most frequently used field in the where clause Join fields in a join statement Select highly selective fields (if a few fields have the same value and there are many unique values,

SQL> host operating system commands; execute operating system commands in SQL * plus.User-managed backupFull backup:Data files, control files, redo logs, or archive files (optional), parameter files, and password files Obtain database file

Add a mysql user group and a mysql userGroupadd mysqlUseradd-g mysqlPasswd-u mysql 1. Install the required software packageYum install gcc-c ++ libtool autoconf automake imake libxml2-devel expat-develYum install ncurses-devel makeYum install

Source code: xx. pc /*  Function: demonstrates Oracle non-scroll cursor operations    Considerations when defining a cursor:  1. The declare cursor statement must be the first statement to use the CURSOR.  2. The cursor name is an identifier

I. Environment Introduction IP_Address Port_No Node_name Service_name Desc 192.168.56.101 3306 SQL node) Mysqld SQL node (API node) 192.168.56.101 2202 Data Node Ndbd Data Node 1

JDBC calls the Oracle stored procedure to return the result set and obtain the output parameters: PackageXx. qq. app; ImportJava. SQL. CallableStatement; ImportJava. SQL. Connection; ImportJava. SQL.

Recently, due to system cleanup, the optimizer accidentally deleted oralce's log file, and Oracle reported ORA-00313 and ORA-00312 errors when the result was started. Run the following command in "run": sqlplusw/nologSQL> conn/as

Generally, it is easier for a database to obtain the dbid through mount. C: \ Users \ Liangwei> rman target/ Recovery MANAGER: Release 10.2.0.3.0-Production on Friday Aug 17 21:29:05 2011 Copyright (c) 1982,200 5, Oracle. All rights