Design Question (Database Polling)

Hi,
I need to write a program that will basically look for any records being added in a Database table e.g. Requests. If there are any records picks them up one by one and calls a Web Service gets a response and inserts in some other table e.g Response, updates the column in Requests table so next time the same record is not picked up again. Before picking up the next record waits for 3 seconds and if there are no records still keep polling the table every 3 seconds. Now the issue is I may have over 8000 records that needs to be processed in a reasonable time and am trying to figure out a better solution so that all my records gets processed in a reasonable time, the Web Service may take 3-5 seconds to send the response back. I will have this program to run as a windows service all the time. Just trying to find out if it's ok to poll on the database to check for new records and in case of errors how do I make sure my program that runs as a service keep running. Or what else can be a better solution.
I did think of using Advanced Queues as I have an Oracle App. Server. As I haven't used AQ before so am just curious on how to keep track of the messages i.e. if my MDB picksup a message and then it fails due to something how do I again pickup the message does it goes away from the queue once read, is there some kind of retry or something that only remove or mark the message read if my request/response cycle succeeds. As I don't want to delete my request data from the table but just need to mark some field in the table that marks the message as read so it's not picked-up again next time and also if I want to send the same data again I can just go to the table and change the status of the column so that it gets picked-up again for processing. As I haven't used AQ's before so wondering if it does provide this kind of functionality. Any small tutorial will help how to setup AQ's will help a lot.
In my scenario my batch process run every night i.e. a scheduled job that dumps the records in a Request table and there can be any number of records i.e. 5000+. From there I need to process all the records and send them to a Web Service that responds back and insert the response in a separate table. The same process can be run in a real time on demand i.e. from a UI a user can select the submit button and behind the secenes the same route is taken inserts a record in a request table and gets the response the whole cycle takes arround 5-8 seconds. Once a response comes user go to a diffreent screen and sees the response. My concern is in a batch mode when I have so many records that all needs to be processed within a reasonable time. So wondering what is my best way to do this. If any request fails wants to basically also retry or the user can change the flag in for those records in a request table so they are automatically send again.
Any help in this is really appreciated. Using Queues I don't know how the retry works or how I send the same record again if a flag is changed in a table. If using a program to poll on a table is there be any issues with the database connections and using threading if I have 8000+ records what are chances of failure etc.
Just looking for some bright ideas that anyone can share.
Thanks

How database could trigger my J2SE application.That all depends on your databases procedure language... Which database are you using? and does this solution need to be portable between databases?
The only time I've had to "break out" of DPL to run a program it was easy, I just used the languages exec method.
It all depends on your database.
Cheers. Keith.

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Design question for database connection in multithreaded socket-server

Dear community,
I am programming a multithreaded socket server. The server creates a new thread for each connection.
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How should I access the connections from the threads? There are two options:
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Kind regards,
Dak
Message was edited by:
dakger

So your suggestion is to use a static method from a
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If I use singleton pattern, I only create one
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on). The threads use than a static method of this
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Kaj

Question regarding Polling data from database using DB Adapters in BPEL

Hi,
I have the following question regarding Polling data from database using DB Adapters in BPEL -
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Thanks
Ravi

Hi Ravi,
your question seems to have been answered for the question of polling a set of tables with one as the root, and getting back a hierarchical xml representing multiple related tables.
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bpel/samples/tutorials/122.DBAdapter/advanced/polling/PollingForChildUpdates
Thanks
Steve

Database Connection design question

Hello, I have a design question. Awhile back I needed to create a database connection to SQL Server, so I created a class to do it
import java.sql.*;
import java.io.*;
import java.net.MalformedURLException;
import org.w3c.dom.Document;
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@nclow - I will work on trying the Factory Pattern for this over the weekend and post when I finish to see what you think.
@abillconsl - just to make sure I understand, you're saying that I just try to connect and it will cycle through the different database connection possibilities and connect when it finds the right one? If it fails all 3, log an appropriate message. One question I have about this is, I thought I was being object oriented by separating the different types of db connections (Oracle, SQL Server, MySql) into different classes. Am I missing the point of OOP by what I was/am trying to accomplish? Going overboard? Also, does your way try and connect to all 3 even if I connected to one already?
Thx, Grantarchy
Edited by: grantarchy on May 9, 2008 9:50 PM

Database Poller to start the control flow

I am relatively new to BPEL/SOA. I need your help in the design process
I have a design as following:
I have to essentially bring data from DB2 database into Siebel. On the Siebel side I have the Webservices created.
1. rowid, tablename, isTheRowProcessed, timestamp.is the structure of my polling table's structure.
The tablename column will tell me which application table has been updated/inserted with new data.
2. The Database Poller will poll the Polling table every minute and see there is a new row. The BPEL will read the tablename column and fetch the name of the table.
3. Depending on the name of the tablename, a specific Web Service will be invoked which will insert the data into the Siebel system.
for example, if the new row is:
10 TableA NotRead 8/19/2012 10:10:10
The poller should the read above and make it "10 TableA Read 8/19/2012 10:10:10"
Then WebServiceA should be invoked with some data.
Here is My question:
Should it be Async BPEL process or Synchronous process that should have the Poller?
Will Poller kick start sub BPEL processes?

I have a DB poller which has only one row (always just one row) and the Poller would update flag to N from Y.
The DBPoller is set to run every two seconds. I have a flag that is initially set by human to Y. The Poller will flip the value of the flag to N (from Y) and initiate a one-way BPEL process and if the BPEL process will set the Flag back to Y if successful. If the BPEL process fails then the BPEL process will leave the value of the flag to N and the BPEL process sends a mail to the users about the failure. The users after fixing the issue (may be some of the Web Services called by the BPEL are unavailable), will set the flag to Y and the process will continue.
The above intention is supposed to create create an instance id only after entire BPEL is executed. The poller is configured to execute every 2 seconds.
instance_id starttime BPEL Execution time
1 5:00:00 30 seconds
2 5:00:02 20 seconds
3 5:00;04 25 seconds
The above is the scenario is my current execution.
I thought that the second instance would start at 5:00:30 because the flag value would be N from 5:00:00 to 5:00:30 and the BPEL process would set the flag's value to Y at the end of execution of the BPEL process (instance 1). But, to my surprise 2nd instance is starting at 5:00:02 (just because the poller is configured to run every 2 seconds). Even if the poller is configured to run every 2 seconds the poller should not create BPEL process because the Poller at 5:00:02 should see the flag value of N (The poller should only create an instance if the flag's value is Y).
Please clarify this behavior.

SOA real-time design question

Hi All,
We are currently working with SOA Suite 11.1.1.4. I have a SOA application requirement to receive real-time feed for six data tables from an external third party. The implementation consists of five one-way operations in the WSDL to populate the six database tables.
I have a design question. The organization plans to use this data across various departments which requires to replicate or supply the data to other internal databases.
In my understanding there are two options
1) Within the SOA application fork the data hitting the web-service to different databases.
My concern with this approach is what if organizations keep coming with such requests and I keep forking and supplying multiple internal databases with the same data. This feed has to be real-time, too much forking with impact the performance and create unwanted dependencies for this critical link for data supply.2) I could tell other internal projects to get the data from the populated main database.
My concern here is that firstly the data is pushed into this database flat without any constraints and it is difficult to query to get specific data. This design has been purposely put in place to facilitate real-time performance.Also asking every internal projects to get data from main database will affect its performance.
Please suggest which approach should I take (advantage/disadvantage. Apart from the above two solutions, is there any other recommended solution to mitigate the risks. This link between our organization and external party is somewhat like a lifeline for BAU, so certainly don't want to create more dependencies and overhead.
Thanks

I had tried implementing the JMS publisher/subscriber pattern before, unfortunately I experienced performance was not so good compared to the directly writing to the db adapter. I feel the organization SOA infrastructure is not setup correctly to cope with the number of messages coming through from external third party. Our current setup consists of three WebLogic Servers (Admin, SOA, BAM) all running on only 8GB physical RAM on one machine. Is there Oracle guideline for setting up infrastructure for a SOA application receiving roughly 600000 messages a day. I am using SOA 11.1.1.4. JMS publisher/subscriber pattern just does not cope and I see significant performance lag after few hours of running. The JMS server used was WebLogic JMS
Thanks
Edited by: user5108636 on Jun 13, 2011 4:19 PM
Edited by: user5108636 on Jun 13, 2011 7:03 PM

Database polling process

I have created a bpel database polling process to process a single table and use a logical update (mark a column as processed). The table will contain many unprocessed records at any time. I have setup the polling interval 5 Sec and records unlimited for each polling interval and in the process i am calling a stored procedure to insert same data into another database.
My doubts
But It fetches only one record and different instance is created for every Row. Is it normal process?
Why it takes only record after using unlimited option?
why i am asking this means i don't want to call stored procedure for each and every record.
I'm using MS SQL Server 2005.
any one pls let me know what is happening inside.

Depends on how you define performance. DBs are generally designed for this kind of load so you then need to look at the middleware. The concern I always have is how big can this message get. If it can potentially grow big, I would say over 10MB then you could run into trouble if you haven't tuned for that, 1 10MB file could hang your whole system if not tuned (extreme case to make a point). If you have it running row by row it may take more time but they will go though. Without knowing more about your environment I can't comment too much more, e.g. patterns, hardware, load etc.
Also polling isn't the most effective way long term to invoke a message. If the table is going to grow large I would look at partitioning as that select statement will deteriorate over time as you don't delete the records once read. ( I'm just trying to give you things to think about it may not be relevant your your site)
cheers
James

Design question - add another table or another column?

Hi there,
quick design question:
I have the following tables:
Traveler
CreditCard
Group
A traveler is going with group X and pay (creditCard) with Y. he can go on multiple groups and can pay with Y or Z...
my question is this:
should I make another table CrditCard_Group which will have the following columns:
user_id
group_id
creditCard_id
or simply to have in the creditCard table another column: Group_id
thanks for any advise

This is not JDBC nor Java, it's database modeling.
Said this, the answer is: it depends; if you have to record the fact that a traveler belonging to a group pays with credit card X you need the table with three ids. If you just need to record the traveler using a credit card and the traveler belonging to a group you need two tables each with the two ids.

Design question: Scheduling a Variable-timeslot Resource

I originally posted this in general java programming, because this seemed like a more high-level design descussion. But now I see some class design questions. Please excuse me if this thread does not belong here (this is my first time using the forum, save answering a couple questions).
Forum,
I am having trouble determining a data structure and applicable algorithm (actually, even more general than the data structure -- the general design to use) for holding a modifiable (but more heavily read/queried than updated), variable-timeslot schedule for a given resource. Here's the situation:
Let's, for explanation purposes, say we're scheduling a school. The school has many resources. A resource is anything that can be reserved for a given event: classroom, gym, basketball, teacher, janitor, etc.
Ok, so maybe the school deal isn't the best example. Let's assume, for the sake of explanation, that classes can be any amount of time in length: 50 minutes, 127 minutes, 4 hours, 3 seconds, etc.
Now, the school has a base operation schedule, e.g. they're open from 8am to 5pm MTWRF and 10am to 2pm on saturday and sunday. Events in the school can only occur during these times, obviously.
Then, each resource has its own base operation schedule, e.g. the gym is open from noon to 5pm MTWRF and noon to 2pm on sat. and sun. The default base operation schedule for any resource is the school which "owns" the resource.
But then there are exceptions to the base operation schedule. The school (and therefore all its resources) are closed on holidays. The gym is closed on the third friday of every month for maintenance, or something like that. There are also exceptions to the available schedule due to reservations. I've implemented reservations as exceptions with a different status code to simplify things a little bit: because the basic idea is that an exception is either an addition to or removal from the scheduleable times of that resource. Each exception (reservation, closed for maintenance, etc) can be an (effectively) unrestricted amount of time.
Ok, enough set up. Somehow I need to be able to "flatten" all this information into a schedule that I can display to the user, query against, and update.
The issue is complicated more by recurring events, but I think I have that handled already and can make a recurring event be transparent from the application point of view. I just need to figure out how to represent this.
This is my current idea, and I don't like it at all:
A TimeSlot object, holding a beginning date and ending date. A data structure that holds list of TimeSlot objects in order by date. I'd probably also hold an index of some sort that maps some constant span of time to a general area in the data structure where times around there can be found, so I avoid O(n) time searching for a given time to find whether or not it is open.
I don't like this idea, because it requires me to call getBeginningDate() and getEndDate() for every single time slot I search.
Anyone have any ideas?

If I am correct, your requirement is to display a schedule, showing the occupancy of a resource (open/closed/used/free and other kind of information) on a time line.
I do not say that your design is incorrect. What I state below is strictly my views and should be treated that way.
I would not go by time-slot, instead, I would go by resource, for instance the gym, the class rooms (identified accordingly), the swimming pool etc. are all resources. Therefore (for the requirements you have specified), I would create a class, lets say "Resource" to represent all the resources. I would recommend two attributes at this stage ("name" & "identifier").
The primary attribute of interest in this case would be a date (starting at 00:00hrs and ending at 24:00hrs.), a span of 24hrs broken to the smallest unit of a minute (seconds really are not very practical here).
I would next encapsulate the availability factor, which represents the concept of availability in a class, for instance "AvailabilityStatus". The recommended attributes would be "date" and "status".
You have mentioned different status, for instance, available, booked, closed, under-maintainance etc. Each of these is a category. Let us say, numbered from 0 to n (where n<128).
The "date" attribute could be a java.util.Date object, representing a date. The "status", is byte array of 1440 elements (one element for each minute of the day). Each element of the byte array is populated by the number designation of the status (i.e, 0,1,2...n etc.), where the numbers represent the status of the minute.
The "Resource" class would carry an attribute of "resourceStatus", an ordered vector of "ResourceStatus" objects.
The object (all the objects) could be populated manually at any time, or the entire process could be automated (that is a separate area).
The problem of representation is over. You could add any number of resources as well as any number of status categories.
This is a simple solution, I do not address the issues of querying this information and rendering the actual schedule, which I believe is straight forward enough.
It is recognized that there are scope for optimizations/design rationalization here, however, this is a simple and effective enough solution.
regards
[email protected]

Someone please help me Design the database of bill of materials

I want to design the database of bill of materials which contain item and amount.
So the amount of child will depend on amount of parent in term of ratio. For example
A(1) A(2)
| ----> |
B(2) B(4)
My problem is when i try to add the parent and child . Let A is the parent of B , If i try to add A to be the child of C
I want B to come along with A as well. For example
A C
| C ---> | For this I have to store the relation of all item in my list to check that this item have a child or not if yes
B A The child must come along with its parent , What the Er-diagram
should be for all of my requirement?
|
B

>I want B to come along with A as well. For example
You can do that, but that is not automatic. You need to do some programming.
It is better to use hierarchyid representation of the tree over traditional FK referencing.
Tree using hierarchyid example:
http://www.sqlusa.com/bestpractices2008/orgchart/
BOL: "Model Your Data Hierarchies With SQL Server 2008
.....The manufacturing system behind automobiles; the organization of a country into states, counties, cities, and postal codes; the description of a home entertainment system—what do these things have in common? The simple answer is that each
describes a hierarchy.
SQL Server 2008 supports a new data type, HierarchyID, that helps solve some of the problems in modeling and querying hierarchical information. I will introduce you to this data type by discussing a pattern commonly used in manufacturing
known as bill of materials (BOM), or bills. Starting with a brief discussion of BOMs, I will illustrate how this kind of data can be modeled. I will also present an implementation of this model in SQL Server 2005. Then I will show you how the HierarchyID data
type can be used to implement the model in SQL Server 2008.
Hierarchical Data
Automobiles are amalgamations of many components, such as engines, drivetrains, electronics, and steering. In the United States, our geographic territories are divided into states and are then sub-divided into jurisdictions called counties.
Counties are then further subdivided in different ways by different agencies. The United States Census Bureau, for example, composes them from Census Tract Areas. The U.S. Postal Service routes mail delivery by Zone Improvement Plan (ZIP) codes. Geographic
information systems (GIS) may aggregate census tracts and ZIP codes together to provide users with a familiar spatial reference for an area.
A recent trip to a local electronics store to evaluate a replacement home entertainment system pointed to a similar sort of hierarchical system—all the combinations of possible components and options left my head spinning! I wondered
how such systems could be modeled and implemented in a database system.
The relationship between an automobile and its engine represents a hierarchy: the automobile contains the engine. The relationship is the same for the drivetrain, the electronics, and the steering. The relationship is containment. A
similar hierarchy can be observed in the relationship between the different groupings of geographic or census data.
Hierarchies exist everywhere, yet implementing them in the context of a relational database frequently proves to be a challenge. A typical approach is to represent the hierarchy using a parent/child relationship with one or more tables.
While this approach certainly works in many cases, it has a few shortcomings. Such solutions must carefully consider how the referential integrity will be maintained. And while querying the depth and breadth of such tables was considerably simplified in SQL
Server 2005 with the introduction of recursive common table expressions, writing queries against these types of tables can still be problematic when joins against many tables are required.
A Bill of Materials Problem
A few years ago I was working on a system being developed by a manufacturing company to help their dealers specify the components needed to build center-pivot irrigation systems. The software produced a list of components needed to custom-build
the desired pivot (the totality of a center-pivot irrigation system is simply referred to as a pivot within the industry). The required components were determined based on geography, soil type, and the intended crops planted in the areas to be covered as well
as the hydrologic and structural considerations of the device itself.
Underpinning the solution would be a SQL Server database. The purpose of the database was to store information about the components available to build the pivot. However, when we generated the specification for manufacturing, we needed
to identify those components as BOMs.
Some bills represented a collection of physical parts that would be assembled into a system component. For example, every pivot needed a pump to draw water from a well into the system. That pump might be electrically powered, meaning
it needed a transformer and fuse box, too. Or the pump might be fuel powered, meaning it needed a tank, a fuel pump, and hoses to connect the pump to the tank. In either case, the required parts for the pump would be listed in a pump bill.
The bill for a complete pivot would include a collection of other bills. For example, a standardized pivot might consist of a tree of bills for the pump, another tree of bills for the spans of pipe used to deliver water, and bills for any other equipment
needed to build that pivot system."
LINK: http://msdn.microsoft.com/en-us/magazine/cc794278.aspx
Kalman Toth Database & OLAP Architect
SELECT Query Video Tutorial 4 Hours
New Book / Kindle: Exam 70-461 Bootcamp: Querying Microsoft SQL Server 2012

Someone please help me Design the database of bill of materials with 1 item can have mutiple parent

I got this sample from Uri
Dimant (MCC, MVP) ,
The problem is i want 1 item to have multiple parent but this example don t let 1 item to have multiple parents. this is not suit for my objective.
CREATE TABLE Employees
empid int NOT NULL,
mgrid int NULL,
empname varchar(25) NOT NULL,
salary money NOT NULL,
CONSTRAINT PK_Employees PRIMARY KEY(empid),
CONSTRAINT FK_Employees_mgrid_empid
FOREIGN KEY(mgrid)
REFERENCES Employees(empid)
CREATE INDEX idx_nci_mgrid ON Employees(mgrid)
SET NOCOUNT ON
INSERT INTO Employees VALUES(1 , NULL, 'Nancy' , $10000.00)
INSERT INTO Employees VALUES(2 , 1 , 'Andrew' , $5000.00)
INSERT INTO Employees VALUES(3 , 1 , 'Janet' , $5000.00)
INSERT INTO Employees VALUES(4 , 1 , 'Margaret', $5000.00)
INSERT INTO Employees VALUES(5 , 2 , 'Steven' , $2500.00)
INSERT INTO Employees VALUES(6 , 2 , 'Michael' , $2500.00)
INSERT INTO Employees VALUES(7 , 3 , 'Robert' , $2500.00)
INSERT INTO Employees VALUES(8 , 3 , 'Laura' , $2500.00)
INSERT INTO Employees VALUES(9 , 3 , 'Ann' , $2500.00)
INSERT INTO Employees VALUES(10, 4 , 'Ina' , $2500.00)
INSERT INTO Employees VALUES(11, 7 , 'David' , $2000.00)
INSERT INTO Employees VALUES(12, 7 , 'Ron' , $2000.00)
INSERT INTO Employees VALUES(13, 7 , 'Dan' , $2000.00)
INSERT INTO Employees VALUES(14, 11 , 'James' , $1500.00)
WITH EmpCTE(empid, empname, mgrid, lvl)
AS
-- Anchor Member (AM)
SELECT empid, empname, mgrid, 0
FROM Employees
WHERE empid = 1
UNION ALL
-- Recursive Member (RM)
SELECT E.empid, E.empname, E.mgrid, M.lvl+1
FROM Employees AS E
JOIN EmpCTE AS M
ON E.mgrid = M.empid
SELECT * FROM EmpCTE
My object is
I want to design the database of bill of materials which contain item and amount.
So the amount of child will depend on amount of parent in term of ratio. For example
A(1) A(2)
| ----> |
B(2) B(4)
My problem is when i try to add the parent and child . Let A is the parent of B , If i try to add A to be the child of C
I want B to come along with A as well. For example
A C
| C ---> | For this I have to store the relation of all item in my list to check that this item have a child or not if yes
B
A The child must come along with its parent , What the Er-diagram should be for all of my requirement?
|
B
Base on the example that Uri
Dimant gave me , i have to stroe 1 item wtih multi parents for example if b is a child of a And b have c as child , When i insert D as a parent of B , c will automatic come along with B , But this not seem gonna work.
item Parent
A NULL
B A
C B
B D
Am i wrong to go this way , any idea

thanks Uri
Dimant
I am
little confuse about how can i write
hierarchy sql from this relation , Thanks
so far i got
WITH EmpCTE(cid, cname, pid, lvl)
AS
SELECT cid , cname , children.pid , 0
FROM children INNER JOIN
parents ON children.pid = parents.pid
where cid = 1
UNION ALL
SELECT E.cid , E.cname , E.pid , M.lvl+1
FROM ( select cid , cname , children.pid FROM children INNER JOIN
parents ON children.pid = parents.pid) AS E JOIN EmpCTE AS M
ON E.pid = M.cid
SELECT * FROM EmpCTE

LDAP design question for multiple sites

LDAP design question for multiple sites
I'm planning to implement the Sun Java System Directory Server 5.2 2005Q1 for replacing the NIS.
Currently we have 3 sites with different NIS domains.
Since the NFS over the WAN connection is very unreliable, I would like to implement as follows:
1. 3 LDAP servers + replica for each sites.
2. Single username and password for every end user cross those 3 sites.
3. Different auto_master, auto_home and auto_local maps for three sites. So when user login to different site, the password is the same but the home directory is different (local).
So the questions are
1. Should I need to have 3 domains for LDAP?
2. If yes for question 1, then how can I keep the username password sync for three domains? If no for question 1, then what is the DIT (Directory Infrastructure Tree) or directory structure I should use?
3. How to make auto map work on LDAP as well as mount local home directory?
I really appreciate that some LDAP experta can light me up on this project.

Thanks for your information.
My current environment has 3 sites with 3 different NIS domainname: SiteA: A.com, SiteB:B.A.com, SiteC:C.A.com (A.com is our company domainname).
So everytime I add a new user account and I need to create on three NIS domains separately. Also, the password is out of sync if user change the password on one site.
I would like to migrate NIS to LDAP.
I want to have single username and password for each user on 3 sites. However, the home directory is on local NFS filer.
Say for userA, his home directory is /user/userA in passwd file/map. On location X, his home directory will mount FilerX:/vol/user/userA,
On location Y, userA's home directory will mount FilerY:/vol/user/userA.
So the mount drive is determined by auto_user map in NIS.
In other words, there will be 3 different auto_user maps in 3 different LDAP servers.
So userA login hostX in location X will mount home directory on local FilerX, and login hostY in location Y will mount home directory on local FilerY.
But the username and password will be the same on three sites.
That'd my goal.
Some LDAP expert suggest me the MMR (Multiple-Master-Replication). But I still no quite sure how to do MMR.
It would be appreciated if some LDAP guru can give me some guideline at start point.
Best wishes

Database Poller issues in Clustered env

Hi,
I am running Oracle BPEL 10.1.3.4 on top of Weblogic version 9.x in a clustered env. I created a simple database poller BPEL process (for target table in Oracle database) with below parameters:
Max Raise Size: 1
Max Transaction Size: 2
Polling Interval:30
Distributed Polling is enabled
All other BPEL engine and domain level parameters have default values.
In my clustered env two instances of database poller BPEL process are running on diff nodes. Now I populated my table with 1000 records in one go. According to parameters I expect:
- In each polling interval max 2 record will be processed by database poller BPEL process running on single node. And there will be 2 instances of this bpel process as max raise size is 1. Same I expect for database poller BPEL process running on another node. So overall 4 records should be processed in each polling interval and 4 instances of BPEL processes should be visible in BPEL console. But in actual its always 2.
Is I am missing something here? Won't the load balancer distributes records to BPEL processes on both nodes equally?
Also then I raise Max transaction size to higher value e.g. 20. But in this case after processing nearly 1/3 rd of records, the BPEL process stopped picking up any further records. Is there any known issue where Adapter stops picking any further database records if transaction size limit is higher?
thanks
Ankit
Edited by: AnkitAggarwal on 22-Feb-2010 03:36

Hi Ankit,
I have Oracle BPEL env11.1.1.2.0 clustered over 2 nodes.
I am facing a similar issue. In my scenario I have Bpel (with DB poller) and its deployed on the cluster. And I am connected to DB via Multi data source (MDS-1) with only one datasource (DS-1) configured in it.
So whenever I update the table which is being polled, in some cases I have TWO instances and in some cases I have ONE Instance running. My requirement is to have only one instance running every time the DB poller is initiatied.
Kindly help me out.
Thank You
Best Regards
Prasanth

Database polling performance issues

I am using Database polling to detect database changes for OLTP application.
my doubts are
1) will it affect performance of OLTP application
2) If so what would be the impact on OLTP application
3) How we can improve performance
4) any link to get more idea about this.

1) will it affect performance of OLTP application
No IT WONT AFFECT BECAUSE oltp Aapplication has
Transactions that involve small amounts of data
* Indexed access to data
* Many users
* Frequent queries and updates
* Fast response times
2) If so what would be the impact on OLTP application
N/A
3) How we can improve performance
Do not poll the table for 30 secs interval poll for atleast 45 secs intervals
4) any link to get more idea about this.
N/A

Workflow design questions: FM vs WF to call FM

Hereu2019s a couple of workflow design questions.
1. We have Workitem 123 that allow user to navigate to a custom transaction TX1. User can make changes in TX1. At save or at user command of TX1, the program will call a FM (FM1) to delete WI 123 and create a new WI to send to a different agent.
Since Workitem 123 is still open and lock, the FM1 cannot delete it immediately, it has to use a DO loop to check if the Workitem 123 is dequeued before performing the WI delete.
Alternative: instead of calling the FM1, the program can raise an event which calls a new workflow, which has 1 step/task/new method which call the FM1. Even with this alternative, the Workitem 123 can still be locked when the new workflowu2019s task/method calls the FM1.
I do not like the alternative, which calls the same FM1 indirectly via a new workflow/step/task/method.
2. When an application object changes, the user exit will call a FMx which is related to workflow. The ABAP developer do not want to call the FMx directly, she wants to raise an event which call a workflow .. step .. task .. method .. FMx indirectly. This way any commit that happens in the FMx will not affect the application objectu2019s COMMIT.
My recommendation is to call the FMx using u2018in Update tasku2019 so that the FMx is only called after the COMMIT of the application object.
Any recommendation?
Amy

Mike,
Yes, in my first design, the TX can 1. raise a terminating event for the existing workitem/workflow and then 2. raise another event to call another workflow. Both 1 and 2 will be in FM1.
Then the design question is: Should the FM1 be called from TX directly or should the TX raise an event to call a new workflow which has 1 step/task, which calls a method in the Business object, and the method calls the FM1?
In my second design question, when an application object changes, the user exit will call a FMx which is related to workflow. The ABAP developer do not want to call the FMx directly, she wants to raise an event which call a workflow, which has 1 step/task, which calls a method, which calls the FMx indirectly. This way any commit that happens in the FMx will not affect the application objectu2019s COMMIT.
My recommendation is either call the FMx using u2018in Update tasku2019 so that the FMx is only called after the COMMIT of the application object or raise an event to call a receiver FM (FMx).
Thanks.
Amy

Design Question (Database Polling)

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