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zabbix监控oracle数据库

Jun 07, 2016 pm 04:10 PM
oracle zabbix database monitor Introduction

一、简介 Orabbix 是设计用来为 zabbix 监控 Oracle 数据库的插件,它提供多层次的监控,包括可用性和服务器性能指标。 它提供了从众多 Oracle 实例采集数据的有效机制,进而提供此信息的监控和性能指标。然后,您可以利用的 zabbix 的报告功能为收集的所有

一、简介

Orabbix 是设计用来为 zabbix 监控 Oracle 数据库的插件,它提供多层次的监控,包括可用性和服务器性能指标。

它提供了从众多 Oracle 实例采集数据的有效机制,进而提供此信息的监控和性能指标。然后,您可以利用的 zabbix 的报告功能为收集的所有数据,并提供分析。目前的发行版中包含了一组预先定义的模板,包括从初始部署警报和图形功能。然而,这些可以进行微调,以满足您的需求和数据/监控要求。

 

 

Orabbix 监控什么?

  1. 数据库版本

  2. 归档日志与生产趋势分析

  3. 触发器,表/过程等命中率

  4. 逻辑 I/O 性能

  5. 物理 I/O 性能

  6. PGA

  7. SGA

  8. 共享池

  9. Sessions

数据库大小

 

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二、安装配置

 

# mkdir /opt/orabbix

 

# cd /opt/orabbix

 

# unzip orabbix-1.2.3.zip

 

# mvconf/config.props.sample conf/config.props

 

# cp init.d/orabbix /etc/init.d/

 

# chmod 755 /etc/init.d/orabbix

 

# chkconfig orabbix on

 

 

 

 

 

三、修改 orabbix 配置

 

# vim conf/config.props

 

#comma separed list of Zabbix servers

 

ZabbixServerList=ZabbixServer

 

ZabbixServer.Address=192.168.0.180

 

ZabbixServer.Port=10051

 

#pidFile

 

OrabbixDaemon.PidFile=./logs/orabbix.pid

 

#frequency of item's refresh

 

OrabbixDaemon.Sleep=300

 

#MaxThreadNumber should be >= thanthe number of your databases

 

OrabbixDaemon.MaxThreadNumber=100

 

#put here your databases in a commaseparated list

 

DatabaseList=192.168.0.70 # 名称与该机在 zabbix 中监控的主机名称保持一致

 

#Configuration of Connection pool

 

#if not specified Orabbis is going touse default values (hardcoded)

 

#Maximum number of active connectioninside pool

 

DatabaseList.MaxActive=10

 

#The maximum number of milliseconds thatthe pool will wait

 

#(when there are no availableconnections) for a connection to be returned

 

#before throwing an exception, or <=0 to wait indefinitely.

 

DatabaseList.MaxWait=100

 

DatabaseList.MaxIdle=1

 

#define here your connection string foreach database

 

192.168.0.70.Url=jdbc:oracle:thin:@192.168.0.70:32778:southdb # 需要 jdk 环境,因为这里是通过 JDBC 连接的,southdb 为数据库实例名称

 

192.168.0.70.User=ZABBIX # 用来监控 oracle 数据库的用户名和密码,需要在 oracle 中创建并赋予一定的权限

 

192.168.0.70.Password=ZABBIX

 

#Those values are optionals if notspecified Orabbix is going to use the general values

 

192.168.0.70.MaxActive=10

 

192.168.0.70.MaxWait=100

 

192.168.0.70.MaxIdle=1

 

192.168.0.70.QueryListFile=./conf/query.props

 

#DB2.Url=jdbc:oracle:thin:@server2.domain.example.com:<LISTENER_PORT>:DB2

 

#DB2.User=zabbix

 

#DB2.Password=zabbix_password

 

#DB2.QueryListFile=./conf/query.props

 

#DB3.Url=jdbc:oracle:thin:@server3.domain.example.com:<LISTENER_PORT>:DB3

 

#DB3.User=zabbix

 

#DB3.Password=zabbix_password

 

#DB3.QueryListFile=./conf/query.props

 

 

 

 

 

 

 

 

 

关于 jdbc:

 

Oracle = jdbc:oracle:thin:@<host>:<LISTENER_PORT>:<instance>

 

PostgreSQL = jdbc:postgresql://<host>:<port>/<database>

 

MS Sql Server = jdbc:jtds:sqlserver://<host>:<port>/<instancename>

 

MySQL Server = jdbc:mysql://[host:port],[host:port].../[database]

 

DB2 = jdbc:db2://<servername>:<port>/<installation>

 

 

 

 

 

 

 

 

 

四、创建 oracle 监控账户

 

1、登录 oracle 命令行

 

su - oracle # 切换到 oracle 用户

 

sqlplus /nolog # 不连接任何数据库

 

conn /as sysdba # 用sysdba 登陆

 

 

conn 用户名/密码

 

select instance_name from v$instance; # 查看实例

 

 

 

2、创建用户

 

CREATE USER ZABBIX

 

IDENTIFIED BY ZABBIX

 

DEFAULT TABLESPACE SYSTEM

 

TEMPORARY TABLESPACE TEMP

 

PROFILE DEFAULT

 

ACCOUNT UNLOCK;

 

 

 

3、赋予角色权限

 

GRANT CONNECT TO ZABBIX;

 

GRANT RESOURCE TO ZABBIX;

 

ALTER USER ZABBIX DEFAULT ROLEALL;

 

 

 

4、赋予系统权限

 

GRANT SELECT ANY TABLE TOZABBIX;

 

GRANT CREATE SESSION TO ZABBIX;

 

GRANT SELECT ANY DICTIONARY TOZABBIX;

 

GRANT UNLIMITED TABLESPACE TOZABBIX;

 

GRANT SELECT ANY DICTIONARY TOZABBIX;

 

 

 

 

 

五、启动服务

 

/etc/init.d/orabbix start

 

 

/opt/orabbix/run.sh

 

 

 

在启动服务过程中通过 tail -f /opt/orabbix/logs/orabbix.log日志查看报错信息。

 

 

 

六、zabbix server 端配置

 

将该模板 Orabbix_export_full.xml 下载到本机,差导入 zabbix server template

 

# sz orabbix/template/Orabbix_export_full.xml

Copy after login

wKiom1Rlv6iQ_IkoAAJEtv07_R8358.jpg

将模板绑定到要监控的主机上:

 

wKiom1Rlv6iTo3WsAAR3Gp0R1ms142.jpg

wKioL1RlwBfBGOZIAANPq43h3j8674.jpg

附:官方文档

 

http://www.smartmarmot.com/wiki/index.php/Orabbix

 

Assumptions

 

Theinstallation instructions have been created based on instructions for most *nixdeployments (i.e. RHEL/CentOS), and is assumed that any alterations requiredfor your specific environment are to be taken into account accordingly.

 

Thisguide is based upon there being two (2) Hosts, 1x Zabbix Server and 1x OracleServer. If you are planning on monitoring an Oracle instance that is running onyour Zabbix Server, the steps are the same, with minor adjustments required foryour connection information.

 

Thesteps also assume you are configuring Orabbix to monitor a new installation orsetup of Oracle. The installation steps will have you GRANT access for theZabbix user to all tables, and this will include any USER tables present at thetime of execution. If you do not want Zabbix to have access to specific tablesor resources within your database, you will need to set a DENY to the Zabbixusers access as required. Consult your DBA for details, as this is beyond thescope of these instructions.

 

Stepsfor Installation

 

Download Orabbix to your Zabbix Server

 

On your Zabbix server, unzip Orabbix to: /opt/orabbix

 

Copy file /opt/orabbix/init.d/orabbix to /etc/init.d/orabbix

 

Grant execute permissions to the following files:

 

/etc/init.d/orabbix

 

/opt/orabbix/run.sh

 

Create a User (ZABBIX) for Orabbix to access your Oracle Database. You can use the following script:

 

 

 

CREATE USER ZABBIX

 

IDENTIFIED BY ZABBIX

 

DEFAULT TABLESPACE SYSTEM

 

TEMPORARY TABLESPACE TEMP

 

PROFILE DEFAULT

 

ACCOUNT UNLOCK;

 

 

 

– 2 Roles for ZABBIX

 

GRANT CONNECT TO ZABBIX;

 

GRANT RESOURCE TO ZABBIX;

 

ALTER USER ZABBIX DEFAULT ROLE ALL;

 

 

 

– 5 System Privileges for ZABBIX

 

GRANT SELECT ANY TABLE TO ZABBIX;

 

GRANT CREATE SESSION TO ZABBIX;

 

GRANT SELECT ANY DICTIONARY TO ZABBIX;

 

GRANT UNLIMITED TABLESPACE TO ZABBIX;

 

GRANT SELECT ANY DICTIONARY TO ZABBIX;

 

 

 

NOTE if you need an User (ZABBIX) for Orabbix with the minimum grants available, you can use the following script:

 

CREATE USER ZABBIX

 

IDENTIFIED BY ZABBIX

 

DEFAULT TABLESPACE USERS

 

TEMPORARY TABLESPACE TEMP

 

PROFILE DEFAULT

 

ACCOUNT UNLOCK;

 

GRANT ALTER SESSION TO ZABBIX;

 

GRANT CREATE SESSION TO ZABBIX;

 

GRANT CONNECT TO ZABBIX;

 

ALTER USER ZABBIX DEFAULT ROLEALL;

 

GRANT SELECT ON V_$INSTANCE TOZABBIX;

 

GRANT SELECT ON DBA_USERS TOZABBIX;

 

GRANT SELECT ON V_$LOG_HISTORYTO ZABBIX;

 

GRANT SELECT ON V_$PARAMETER TOZABBIX;

 

GRANT SELECT ON SYS.DBA_AUDIT_SESSIONTO ZABBIX;

 

GRANT SELECT ON V_$LOCK TOZABBIX;

 

GRANT SELECT ON DBA_REGISTRY TOZABBIX;

 

GRANT SELECT ON V_$LIBRARYCACHETO ZABBIX;

 

GRANT SELECT ON V_$SYSSTAT TOZABBIX;

 

GRANT SELECT ON V_$PARAMETER TOZABBIX;

 

GRANT SELECT ON V_$LATCH TOZABBIX;

 

GRANT SELECT ON V_$PGASTAT TOZABBIX;

 

GRANT SELECT ON V_$SGASTAT TOZABBIX;

 

GRANT SELECT ON V_$LIBRARYCACHETO ZABBIX;

 

GRANT SELECT ON V_$PROCESS TOZABBIX;

 

GRANT SELECT ON DBA_DATA_FILESTO ZABBIX;

 

GRANT SELECT ON DBA_TEMP_FILESTO ZABBIX;

 

GRANT SELECT ON DBA_FREE_SPACETO ZABBIX;

 

GRANT SELECT ON V_$SYSTEM_EVENTTO ZABBIX;

 

 

 

NOTE : If you are using Oracle 11g, you will need to add the following:

 

exec dbms_network_acl_admin.create_acl(acl=> 'resolve.xml',description => 'resolve acl', principal =>'ZABBIX',is_grant => true, privilege => 'resolve');

 

exec dbms_network_acl_admin.assign_acl(acl=> 'resolve.xml', host =>'*');

 

commit;

 

 

 

Youcan verify the above is correct by running:

 

select utl_inaddr.get_host_name('127.0.0.1')from dual;

 

For this example on RedHat, run:

 

chkconfig -add orabbix

 

Verify with:

 

chkconfig -list

 

Create a Host entry in Zabbix for the DB Instance/s you are planning to monitor, and import the templates found at: /opt/orabbix/template

 

Please note, instructions for this step can befound in the Zabbix Manual at

 

http://www.zabbix.com/documentation.php

 

With this step, ensure the name of yourhost in Zabbix is the same name of the SID or Oracle instance name.

 

Configuration

 

Nowwe need to configure your Orabbix setup. The tags below are listed as they willappear within the respective configuration files. The first you will need tomodify is your config.props file to define your connection properties forZabbix and Oracle.

 

config.props

 

Theconfig.props file can be found at /opt/orabbix/conf/config.props

 

ZabbixServerList

 

#comma separed list of Zabbix servers

 

Thesettings under this tag allow you to configure your Zabbix Server information.Orabbix can also be configured to send your Oracle data to multiple Zabbixservers.

 

This can be beneficial for distributedmonitoring scenarios, server migrations or replicating Orabbix data to a Disaster Recovery site or server.

 

Replacewith your Zabbix Server info where appropriate;

 

ZabbixServerList=ZabbixServer1,ZabbixServer2

 

ZabbixServer1.Address=192.168.0.1

 

ZabbixServer1.Port=10051

 

 

 

ZabbixServer2.Address=192.168.0.2

 

ZabbixServer2.Port=10051

 

OrabbixDaemon

 

Entriesunder this tag allow you to set your Orabbix Daemon parameters.

 

#MaxThreadNumber should be >= than thenumber of your databases

 

Setthe number of threads the Orabbix Daemon should have inside his internal poolof DB Jobs. This number should be at least equal to (or more than) then numberof databases monitored by Orabbix, now this parameter if not set isautomatically calculated.

 

e.g.For 50 Databases, we are using 100 threads

 

OrabbixDaemon.MaxThreadNumber=100

 

#pidFile

 

Nextyou can set the location of the Daemons PID file. Default location is:/opt/orabbix/logs

 

OrabbixDaemon.PidFile=./logs/orabbix.pid

 

NOTE: Relative path is permitted here

 

TIP: With the features of the OrabbixDaemon, it is possible to clone Orabbix and use different configurations.

 

As such, it is therefore possible to haveone Daemon that checks your TEST databases, another iteration that checks your

 

DEVELOPMENT databases and a third thatchecks your PRODUCTION databases, each with different timings and check loops!

 

DatabaseList

 

 

 

Thisis where you define your database instances. You can specify more than oneinstance here, separated using a comma.

 

DatabaseList=EXAMPLE1,EXAMPLE2

 

NOTE: The names of the instances must match those you have specified asyour HOST name in Zabbix

 

#Configuration of Connection pool

 

Fromhere, you will configure settings that are specific to the connection pool. Asthe comments in config.props suggest, if you do not specify these values,Orabbix will use default values which have been hard-coded.

 

#Maximum number of active connection insidepool

 

Setthe maximum number of connections that can be allocated to this pool at anytime,or alternatively set a negative value for no limit.

 

DatabaseList.MaxActive=10

 

#The maximum number of milliseconds

 

Hereyou define how long that the pool will wait (when there are no available connections)for a connection to be returned before throwing an exception, or set the value

 

DatabaseList.MaxWait=100

 

Alsounder the same section, you can define the maximum number of connections thatcan remain idle within the connection pool, without being released.Alternatively, you can set a negative value for no limit.

 

DatabaseList.MaxIdle=1

 

TIP: You can specify the Database connection parameters for each database youwish to monitor individually, underneath your Database Connection Parameters.This allows you to customise your connection settings based on the Databaseconstraints I.e one connection pool for your PRODUCTION DB and another for youTEST DB, for example;

 

DB1.MaxActive=10

 

DB1.MaxWait=100

 

DB1.MaxIdle=1

 

Notethat any settings defines this way will override the general settings for yourgeneric connection pool.

 

Database Connection Parameters

 

Thissection sets your connection string to the Oracle Database. This string invokesa Java Database Connector (JDBC) to your Oracle Databases, and as such does notneed the Oracle Client to be installed.

 

#define here your connection string for eachdatabase

 

Hereyou will define the connection string. These are formatted as: DBName.Url(asspecified in your DatabaseList) followed by the jdbc string and your DatabaseServer information.

 

EXAMPLE1.Url=jdbc:oracle:thin:@SERVER1.EXAMPLE.COM:1521:DB1

 

Setyour Database username and password below. e.g.

 

EXAMPLE1.User=zabbix

 

EXAMPLE1.Password=zabbix_password

 

TIP: Setting connections to multiple databases is made easy by adding moreconnection strings, with their corresponding credentials. Example given below.

 

EXAMPLE2.Url=jdbc:oracle:thin:@server2.domain.example.com::EXAMPLE2

 

EXAMPLE2.User=zabbix

 

EXAMPLE2.Password=zabbix_password

 

EXAMPLE3.Url=jdbc:oracle:thin:@server3.domain.example.com::EXAMPLE3

 

EXAMPLE3.User=zabbix

 

EXAMPLE3.Password=zabbix_password

 

NOTE:After these entries, you can set your MaxActive, MaxWait and MaxIdle forthe individual database connections if you so wish.

 

Thereis a pair of default parameter:

 

DefaultUser =

 

DefaultPassword =

 

thisdefault parameter can be overridden using the following pair

 

.User and .User

 

Itis only possible to override Username or Password.

 

Query List File

 

Thisdefines where the file containing the Oracle (SQL) queries can be found. Thisis a customisable file. You can find the query parameter file at:

 

QueryListFile=/opt/orabbix/conf/query.props

 

youcan also specify :

 

.QueryListFile=./confQueryTest.propsthis file specify the query file of adatabase relative path are allowed

 

TIP: This is really useful to use different query file for differentdatabases or to have a pool of query file one for each

 

OracleRelease (if you have different release) and/or to have different query filesfor Production environment, Test environment, Developement environment etc..

 

thefollowing parameter

 

.ExtraQueryListFile==./confQueryTest_2.props

 

addsanother custom query to the default query file. If there are duplicates theExtraQueryListFile will override them.

 

query.props

 

Configurationof query.props file

 

Thequery.props file can be modified or added to, so you can supply your owncustomised queries through Orabbix against your Oracle instances/databases.Each query created has an associated 'Item' or item name that Zabbix will useto identify the query.

 

NOTE: Item names must be unique.

 

Theconfigurable items are formatted as follows.

 

 

 

Youhave to set the query name under the QueryList in the query.props file. Eachquery name is comma separated. For example;

 

QueryList=queryName1,queryName2,queryName3

 

 

 

Youmust identify the query by the unique item name you specified in the QueryList,followed by '.Query' for Orabbix to recognize that this is the query string.Its important to remember NOT to add the semi-colon “;”to the end of your custom query.

 

customQueryItemName.Query=yourQueryHere

 

Nowyou can define what you want Orabbix to return to your Zabbix Server if no datais found for your query.

 

customQueryItemName.NoDataFound=none

 

TIP: In the example above, Orabbix would send the string “none”to the Zabbix Server.

 

Youcan specify if you want a different execution period for your query

 

customQueryItemName.Period=

 

TIP:You can change the execution time of dbversion that don’t change often

 

Nextyou can specify a query that will be executed and if return RaceCondiftionValuethe query customQueryItemName is executed otherwise is skipped

 

customQueryItemName.ACTIVE=[true|false] iftrue query is executed otherwise skipped

 

 

 

archive.Query=select round(A.LOGS*B.AVG/1024/1024/10 ) \

 

from ( SELECT COUNT (*) LOGS FROM V$LOG_HISTORYWHERE \

 

FIRST_TIME >= (sysdate -10/60/24)) A, \

 

( SELECT Avg(BYTES) AVG, Count(1), Max(BYTES) Max_Bytes,Min(BYTES)Min_Bytes FROM v$log) B

 

archive.RaceConditionQuery=select value \

 

from \

 

v$parameter where name='log_archive_start'

 

archive.RaceConditionValue=FALSE

 

TIP:In the example above, Orabbix would execute “archive.Query”only if the query“archive.RaceConditionQuery” return the value “archive.RaceConditionValue”. Pratically the “Archive”query is execute only if database is in arhivelogmode (Parameter “log_archive_start” set to TRUE)

 

.Trim=[true|false]

 

iftrue the resultset is trimmed (default is true)

 

.AddSpaces=[true|false]

 

iftrue the add a space between columns of resultset(default is true)

 

.ExcludeColumnsList=[1,2,3,..n]

 

excludefrom result set the 1st, the 2nd etc.. columns from resultset

 

.Period

 

.WhenNotAlive =

 

isused to specify a value or a string to send if a database is not working, doingsuch will "clean" the graphs generated in Zabbix with a"set" value.

 

 

 

Addedthe following parameter on main configuration file:

 

DefaultUser =

 

DefaultPassword =

 

.ExtraQueryListFile =

 

 

 

onquery's properties file I've added the following parameter:

 

.WhenNotAlive =

 

withthese parameter you can define a default username and password for all thedatabase.

 

DefaultUser =

 

DefaultPassword =

 

thisdefault parameter can be overridden using the couple

 

.User and .User

 

Ispossible to override only Username or Password.

 

thefollowing parameter

 

.ExtraQueryListFile =

 

addanother custom query to a default query file. if there are duplicate theExtraQueryListFile will override them.

 

thefollowing parameter

 

.WhenNotAlive =

 

isused to specify a value or a string to send if a database is not working, doingso you are going to "clean" the graphs generated in Zabbix with a"set" value.

 

Howto Use Orabbix/FAQ

 

How do I start/stop the Daemon?

 

Tostart the Orabbix Daemon, simply run:

 

/etc/init.d/orabbix start

 

 

 

Tostop the Orabbix Daemon, simply run:

 

/etc/init.d/orabbix start

 

 

 

How does Logging work?

 

TheOrabbix daemon outputs its log file to the default location of/opt/orabbix/logs/

 

How to modify Log format?

 

Loggingproperties can be modified by making your required changes to

 

/opt/orabbix/conf/log4j.properties

 

Theproperty setting responsible for defining the output location is:

 

log4j.appender.Orabbix.File=logs/orabbix.log

 

TIP:From this properties file, you can modify the location, file name and logformat as desired. For additional information, please refer to the officiallog4j documentation, found at: http://logging.apache.org/log4j/1.2/index.html

 

Is there a way for orabbix to connect to RAC or DataGuard?

 

Yesis possible.

 

e.g.

 

Ifyou have two host RAC1 and RAC2 and one instance RACINST

 

youshould write the connection string as follow:

 

RACINST.Url=jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=RAC1.EXAMPLE.COM)\

 

(PORT=1521))(ADDRESS=(PROTOCOL=TCP)(HOST=RAC2.EXAMPLE.COM)(PORT=1521)))(CONNECT_DATA=(SERVICE_NAME=RACINST)))

 

Whatcan I modify without restarting the daemon?

 

Theparameters that are dynamically read at each iteration of “OrabbixDaemon.Sleep”are as follows;

 

Any Query added to query.props

 

Modifications to config.props

 

Database List

 

Currently,the only known items that don't dynamically update are theZabbixDaemon.MaxThreadNumber, and changes to Connection Pool info

 

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MySQL: An Introduction to the World's Most Popular Database MySQL: An Introduction to the World's Most Popular Database Apr 12, 2025 am 12:18 AM

MySQL is an open source relational database management system, mainly used to store and retrieve data quickly and reliably. Its working principle includes client requests, query resolution, execution of queries and return results. Examples of usage include creating tables, inserting and querying data, and advanced features such as JOIN operations. Common errors involve SQL syntax, data types, and permissions, and optimization suggestions include the use of indexes, optimized queries, and partitioning of tables.

Why Use MySQL? Benefits and Advantages Why Use MySQL? Benefits and Advantages Apr 12, 2025 am 12:17 AM

MySQL is chosen for its performance, reliability, ease of use, and community support. 1.MySQL provides efficient data storage and retrieval functions, supporting multiple data types and advanced query operations. 2. Adopt client-server architecture and multiple storage engines to support transaction and query optimization. 3. Easy to use, supports a variety of operating systems and programming languages. 4. Have strong community support and provide rich resources and solutions.

What to do if the oracle can't be opened What to do if the oracle can't be opened Apr 11, 2025 pm 10:06 PM

Solutions to Oracle cannot be opened include: 1. Start the database service; 2. Start the listener; 3. Check port conflicts; 4. Set environment variables correctly; 5. Make sure the firewall or antivirus software does not block the connection; 6. Check whether the server is closed; 7. Use RMAN to recover corrupt files; 8. Check whether the TNS service name is correct; 9. Check network connection; 10. Reinstall Oracle software.

How to solve the problem of closing oracle cursor How to solve the problem of closing oracle cursor Apr 11, 2025 pm 10:18 PM

The method to solve the Oracle cursor closure problem includes: explicitly closing the cursor using the CLOSE statement. Declare the cursor in the FOR UPDATE clause so that it automatically closes after the scope is ended. Declare the cursor in the USING clause so that it automatically closes when the associated PL/SQL variable is closed. Use exception handling to ensure that the cursor is closed in any exception situation. Use the connection pool to automatically close the cursor. Disable automatic submission and delay cursor closing.

How to create cursors in oracle loop How to create cursors in oracle loop Apr 12, 2025 am 06:18 AM

In Oracle, the FOR LOOP loop can create cursors dynamically. The steps are: 1. Define the cursor type; 2. Create the loop; 3. Create the cursor dynamically; 4. Execute the cursor; 5. Close the cursor. Example: A cursor can be created cycle-by-circuit to display the names and salaries of the top 10 employees.

How to stop oracle database How to stop oracle database Apr 12, 2025 am 06:12 AM

To stop an Oracle database, perform the following steps: 1. Connect to the database; 2. Shutdown immediately; 3. Shutdown abort completely.

How to create oracle dynamic sql How to create oracle dynamic sql Apr 12, 2025 am 06:06 AM

SQL statements can be created and executed based on runtime input by using Oracle's dynamic SQL. The steps include: preparing an empty string variable to store dynamically generated SQL statements. Use the EXECUTE IMMEDIATE or PREPARE statement to compile and execute dynamic SQL statements. Use bind variable to pass user input or other dynamic values ​​to dynamic SQL. Use EXECUTE IMMEDIATE or EXECUTE to execute dynamic SQL statements.

How to open a database in oracle How to open a database in oracle Apr 11, 2025 pm 10:51 PM

The steps to open an Oracle database are as follows: Open the Oracle database client and connect to the database server: connect username/password@servername Use the SQLPLUS command to open the database: SQLPLUS

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