使用cache或许会跳号, 比如数据库突然不正常down掉(shutdown abort),cache中的sequence就会丢失. 所以可以在create sequence的时候用nocache防止这种情况。 2、Alter Sequence 你或者是该sequence的owner,或者有ALTER ANY SEQUENCE 权限才能改动sequence. 可以alter除start至以外的所有sequence参数.如果想要改变start值,必须...
ORDER Specify ORDER to guarantee that sequence numbers are generated in order of request. This clause is useful if you are using the sequence numbers as timestamps. Guaranteeing order is usually not important for sequences used to generate primary keys. ORDER is necessary only to guarantee ordere...
xttprepareNaNd- the command tsbkupmap.txt- containing the tablespace names, datafile numbers and the incremental backup pieces incrbackups.txt- containing the actual location of the incremental backup pieces rmanincrNaNd- containing the RMAN scripts used to create the incremental backups. xttdetnewfr...
This Oracle tutorial explains how to create and drop sequences in Oracle with syntax and examples.Description In Oracle, you can create an autonumber field by using sequences. A sequence is an object in Oracle that is used to generate a number sequence. This can be useful when you need to...
numbersastimestamps.Guaranteeing order is usually not importantforsequences used to generate primary keys.NOORDERdoes not guarantee sequence numbers are generatedinorderofrequest.If you omit both theORDERandNOORDERoptions,Oracle choosesNOORDERbydefault.Note that theORDERoption is only necessary to ...
CACHENOCACHE NOCACHECACHENOCACHEORDERto guarantee that sequence numbers are generated in order of request. This clause is useful if you are using the sequence numbers as timestamps. Guaranteeing order is usually not important for sequences used to generate primary keys. ...
A sequence is a schema object that can generate unique sequential values. These values are often used for primary and unique keys. You can refer to sequence values in SQL statements with these pseudocolumns: CURRVAL The CURRVAL pseudocolumn returns the current value of a sequence. NEXTVAL The...
21-9 21.1.28 Failure to Send Message to Oracle BAM is Not Reported on Oracle Fusion Middleware Control Console 21-9 21.1.29 Input of Numbers Is Not Localized As Per Browser Locale ... 21-9 21.1.30 Unique Constraint Error in Oracle Data Integrator After Moving a Data Object ... 21-...
Sequence #: 0 RBA: 0 Timestamp: 2011-11-17 16:56:31.777616 Extract Trail: /u01/ggate/dirdat/lt 1.2 Monitoring lag Lag statisticsshow you how well the Oracle GoldenGate processes are keeping pace with theamount of data that is being generated by the business applications. With this informa...
Incremental values, such as ascending sequence numbers or increasingly later date values, are always added to the right side of the index, which is the home of higher and higher values. In addition, any deletions from the index have a tendency to be skewed toward the left side as older ...