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人力:只需要你在工作中肯卖力气就足够了;人手:则需要你熟悉掌握工作，能应付突发事件;人才:则需要你头脑灵活，能够在工作中提出创造性的方案;人物:就需要八面玲珑，用自己特有的方式为公司做出比较大的贡献.[@more@]

1)prior放在子节点端,则表示扫描树是以start with指定的节点作为根节点从上往下扫描.可能对应一个或多个分支.start with可以省略,如果省略,表示对所有节点都当成根节点分别进行遍历.2)prior放在父节点端,则表示扫描树是以start with指定的节点作为最低层子节点,从下往上扫描.顺序是子节点往父节点扫描,直到根节点为止,这种情况只能得到一个分支.start with可以省略,如果省略,表示对所有节点都当成最低层子节点分别往根节点方向遍历.[@more@]

The DBMS_OUTLN and DBMS_OUTLN_EDIT package provides procedures used for managing stored outlines and their outline categories. Users need the EXECUTE_CATALOG_ROLE role to execute DBMS_OUTLN, but public has execute privileges on DBMS_OUTLN_EDIT. The DBMS_OUTLN_EDIT package is an invoker's rights package.Some of the useful DBMS_OUTLN and DBMS_OUTLN_EDIT procedures are:■ CLEAR_USED - Clears specified outline■ DROP_BY_CAT - Drops outlines that belong to a specified category■ UPDATE_BY_CAT - Chang

catalog.sql - create data dictionary views.cataudit.sql - data dictionary views for auditing. (catnoaud.sql will remove)catblock.sql - create views of oracle lockscatclust.sql - create cluster database specific views definitionscatdbsyn.sql - catalog dba synonyms (dba_synonyms.sql)catexp7.sql - create v7 style export/import viewscatexp81.sql - create internal views for export/import utilitycatio.sql - collect i/o per table/object stats by statistical samplingcatjava.sql - catalog scripts for jav

SQL*Plus uses the PRODUCT_USER_PROFILE (PUP) table, a table in the SYSTEM account, to provide product-level security that supplements the user-level security provided by the SQL GRANT and REVOKE commands and user roles.DBAs can use the PUP table to disable certain SQL and SQL*Plus commands in the SQL*Plus environment on a per-user basis. SQL*Plus—not Oracle Database—enforces this security. DBAs can even restrict access to the GRANT, REVOKE, and SET ROLE commands to control users' ability to ch

RMAN automatically backs up the current server parameter file in certain cases. The BACKUP SPFILE command backs up the parameter file explicitly. For example:BACKUP DEVICE TYPE sbt SPFILE;The SPFILE that is backed up is the one currently in use by the instance. If the instance is started with a client-side initialization parameter file, then RMAN does not back up anything when this command is used.[@more@]

You can back up the control file when the database is mounted or open. RMAN uses a snapshot control file to ensure a read-consistent version. If CONFIGURE CONTROLFILE AUTOBACKUP is ON (by default it is OFF), then RMAN automatically backs up the control file and server parameter file after every backup and after database structural changes. The control file autobackup contains metadata about the previous backup, which is crucial for disaster recovery.If the autobackup feature is not set, then you

You can backup one or more individual tablespaces with the BACKUP TABLESPACE command. You can use this command when the database is mounted or open.To back up a tablespace:After starting RMAN, run the BACKUP TABLESPACE command at the RMAN prompt. This example backs up the users and tools tablespaces to tape, using the MAXSETSIZE parameter to specify that no backup set should be greater than 10 MB:BACKUP DEVICE TYPE sbt MAXSETSIZE = 10M TABLESPACE users, tools;Oracle translates the tablespace nam

You can perform whole database backups with the database mounted or open. To perform a whole database backup, from the RMAN prompt, use the BACKUP DATABASE command. The simplest form of the command requires no parameters, as shown in this example:RMAN> BACKUP DATABASE;This example shows the procedure for taking a whole database backup to the default destination:RMAN> BACKUP DATABASE; # uses automatic channels to make backupRMAN> SQL 'ALTER SYSTEM ARCHIVE LOG CURRENT'; # switches logs a

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RMAN can also store backup information a logical structure called a backup set. A backup set contains the data from one or more datafiles, archived redo logs, or control files or SPFILE. (Datafiles and archivelogs cannot be mixed together in the same backup set.) You can also back up existing backup sets into another backup set.A backup set consists of one or more files in an RMAN-specific format, known as backup pieces. By default, a backup set consists of one backup piece. For example, you c

An image copy is a bit-for-bit duplicate of a database file, identical to a copy made with an operating system command. (RMAN-created image copies are, however, recorded in the RMAN repository, unlike file copies created using operating system-level commands.)Image copy backups can only be created on disk. RMAN can create image copies of datafiles and datafile copies, control files and control file copies, archived redo logs, and backup pieces. RMAN creates image copies when the AS COPY option i

RMAN's BACKUP command supports backing up the following types of files:■ Database files, including datafiles, control files, and the server parameter file (SPFILE)■ Archived redo logs■ Other backups created by RMAN, including such as datafile and control file image copies, and backup sets containing SPFILEs, control files, datafiles and archived logs Although the database depends on other types of files for operation, such as network configuration files, password files, and the contents of th

Quotation marks can be nested in one of two ways. The first method is to double the quotation marks in the nested string. For example:NLS_DATE_FORMAT = '''Today is'' MM/DD/YYYY'The second method is to alternate single and double quotation marks. For example:NLS_DATE_FORMAT = '"Today is" MM/DD/YYYY'[@more@]

Character Name Description # Number sign Comment ( Left parenthesis Start list of values ) Right parenthesis End list of values " Double quotation mark Start or end of quoted string ' Single quotation mark Start or end of quoted string = Equal sign Separator of keyword and values , Comma Separator of elements -

If a parameter value contains a special character, then the special character must be preceded by a backslash or the entire parameter value must be enclosed in quotation marks. For example, you can specify special characters using either of the following:DB_DOMAIN = 'JAPAN.ACME#.COM'DB_DOMAIN = JAPAN.ACME#.COM[@more@]

The following rules govern the specification of parameters in initialization parameter files:■ An initialization parameter file should contain only parameters and comments. A pound sign (#) starts a comment line. The rest of the line is ignored.■ You can specify parameters in any order.■ Case (upper or lower) in filenames is significant only if case is significant on the host operating system.■ To enter several parameters on one line, use spaces between parameter names and values, as in the

■ The ashrpt.sql SQL script generates an HTML or text report that displays ASH information for a specified duration. ■ The ashrpti.sql SQL script generates an HTML or text report that displays ASH information for a specified duration for a specified database and instance.[@more@]

You can view AWR reports by running the following SQL scripts:■ The awrrpt.sql SQL script generates an HTML or text report that displays statistics for a range of snapshot Ids. ■ The awrrpti.sql SQL script generates an HTML or text report that displays statistics for a range of snapshot Ids on a specified database and instance. ■ The awrsqrpt.sql SQL script generates an HTML or text report that displays statistics of a particular SQL statement for a range of snapshot Ids. Run this report to i

Typically, you would view the AWR data through Oracle Enterprise Manager screens or AWR reports. However, you can view the statistics with the following views:■ V$ACTIVE_SESSION_HISTORY This view displays active database session activity, sampled once every second. ■ V$ metric views provide metric data to track the performance of the systemThe metric views are organized into various groups, such as event, event class, system, session, service, file, and tablespace metrics. These groups are ide