1、通过风险分析，可加深对项目和风险的认识与理解，澄清个方案的利弊，了解风险对项目的影响，以便减少或分散风险。
2、通过检查和分析所有可用的信息、数据和资料，可明确项目的各有关前提和假设。
3、通过风险分析不但可提高项目各种计划的可信度，还有利于改善项目和外部之间的沟通。
4、编制应急计划时更有针对性。
5、能够将处理风险后果的各种方式更灵活的组合起来，在项目管理中减少被动，增加主动。
6、有利于抓住机会，利用机会。
7.为以后的规划和设计工作提供反馈，以便在规划和设计阶段就采取措施防止和避免风险损失。
8、风险即使无法避免，也能够明确项目到底应该承受多大损失或损害。
9、为项目施工、运营选择合同形式和制订应急计划提供依据。
10、通过深入的研究和情况了解，可以使决策更有把握，更符合项目的方针和目标，从总体上使项目减少风险，保证项目目标的实现。
11、可推动项目执行组织和管理团队积累有关风险的资料和数据，以便改进将来项目管理。
1、对团队成员要有耐心、有好，认为他们都是最好的。参照Y理论，项目团队成员是积极向上的，要给予他们一定的环境发挥他们个人的自我激励、自我控制的能力。千万不要认为他们都是懒惰和粗心大意的人。
2、解决问题而不是责备人。记住一点，“对事不对人”，把解决问题放在首要的位置，而不是去处理人员的责任。
3、召开经常性的、有效的会议。特别是开工会议，注重项目目标的实现以及长期有效的结果。
4、把项目团队建设活动计划到项目计划中去，来帮助项目团队成员和其他的项目干系人更好地相互了解，使项目建设活动变得有趣而又不失强制性的。
5、教育培养仙姑团队成员，鼓励他们互相帮助、认识并提供培训以帮助个人和项目团队成为一个更有效的整体。
6、认可个人和团队的成绩。
7、尽早地进行项目团队建设，在整个项目生命周期中进行持续的项目团队建设。
OAM页在sybase数据库中起着相当重要的作用，管理着单个表的位置信息，通过遍历OAM页，来找到所有的分配页，然后再通过分配页的信息来获取所有该表的页面。
11月1日，增加了读取OAM页和分配页的功能，将OAM页的信息和分配页的信息都以图形化的方式显示
近期有一个客户说他们有一个数据库，出了问题，库又很大，我发传送到本地，远程操作又相当的困难，要求的时间又紧急，就放弃了处理。
处理的过程中发现了自己程序中的一些毛病，比如对于DOL页面处理能力不够，不能像APL表一样，通过页链来直接处理。之前曾经将这方面的工作已经进入到一定的程度，但后来由于工作的关系搁了下来，近期打算更新。
核心的算法已经基本上都完成，但是在展现方面还是存在一定的问题，一直都在思考，陆陆续续再做吧
The Adaptive Server Enterprise scheduler manages the processing time provided to client tasks. The scheduler allows a task to execute on a server engine using the rule:-
The following diagram illustrates management of processing time using default values for time slice (1 clock tick, 1/10th of a second) and cpu grace time (500 clock ticks, 50 seconds). The task begins execution at the end of the “free time”.
At periodic yield points, the task checks to see if the time slice has been exceeded. If it has not, the task continues executing. If it has, the task voluntarily yields the engine within the cpu grace time; if the task had not yet fulfilled the client request, the task goes to the end of the run queue. If there are no other tasks in the run queue, the server grants the task another processing interval.
It is possible for a task not to encounter a yield point and to exceed the time slice period. When this occurs, the server terminates the task with a time slice error at the end of the cpu grace time. Time slice errors are typically due to a delay in acquiring an Adaptive Server resource, a coding problem, or some other issue; for example, the Server may have made a blocking system call that does not return for a long time.
If you receive time slice errors, take these steps:-
Set up a configurable shared memory dump (CSMD) using “timeslice” as the dump condition. Information about CSMD can be found in the section “Other Useful Tasks” in the most recent version of Troubleshooting and Disaster Recovery.
Try increasing the value of the cpu grace time parameter. See “Configuration parameters” in the System Administration Guide: Volume 1 chapter “Setting Configuration Parameters.” Warning! Sybase does not recommend changing the time slice configuration parameter to resolve these errors, only the cpu grace time parameter. Changing the time slice parameter affects all tasks and changes the dynamics of Adaptive Server’s processing time management; changing the cpu grace time affects only tasks that would be terminated with a time slice error. If cpu grace time is set to 1500 and time slice errors persist, contact Sybase Technical Support.
Sometimes one table will be inserted some duplicate rows.example for:
col1 col2 col3
a b c
d e f
a b c
a b c
d e f
—————————–
I want to delete duplicate rows. And the result like:
col1 col2 col3
a b c
d e f
—————————–
How to do?
It is often necessary to identify gaps in sequential data,like key gaps, bcp load gaps, etc.
Here is a simple table with a sequence gap (i.e. the number 4 is missing)
SELECT * FROM number
go
number
———–
1
2
3
5
6
(5 rows affected)
How to find the missing data of 4?
Latches are nontransactional synchronization mechanisms used to guarantee the physical consistency of a page. While rows are being inserted, updated or deleted, only one Adaptive Server process can have access to the page at the same time. Otherwise, changes could overwrite each other. Latches are used for both datapages and datarows locking. They are not used for changes to tables using the allpages locking scheme.
The most important distinction between a lock and a latch is the duration:
A lock can persist for a long period of time: while a page is being scanned, for the duration of a
statement, or for the duration of a transaction.
A latch is held only for the time required to insert or move a few bytes on a data page, to
copy pointers, columns or rows, or to acquire a latch on another index page.
In datarows locking, row-level locks are acquired on individual rows on data pages. Index rows and
pages are not locked. When a row needs to be changed on a data page, a nontransactional latch
is acquired on the page. The latch is held while the physical change is made to the data page, and
then the latch is released. The lock on the data row is held until the end of the transaction. The
index rows are updated, using latches on the page, but are not locked. Index entries are implicitly locked by acquiring a lock on the data row.
环境ASE 12.5.4 WINDOWS
库名test
大小2M
表名pet_goods
dump文件test.dump
步骤：
1 建一个2M的库test，实现方法随便大家
2 load database test from ‘test.dump’
3 online database test
4 bcp test..pet_goods out pet_goods.bcp -c -Usa -Pxxxx
你会发现你的bcp一直都不会结束，直到你中断
dbcc checktable(pet_goods)
————————————–
Table Corrupt: Page linkage is not consistent; check the following pages:
(current page#=631; page# pointing to this page=678; previous page# indicated
in this page=630)
DBCC execution completed. If DBCC printed error messages, contact a user with
System Administrator (SA) role.
————————————–
