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miaoluzeng
New User
Joined: 29 Aug 2007
Posts: 10
Location: CHINA
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hi all,
the GU GHU GN GNP call.. is difficult for a relational databaser,but as i know the hierarchic database is a kind of relational database.as a pgmer i do not want and need to know the physical operation,so can any tools or program translate sql to ims calls? |
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dick scherrer
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Joined: 23 Nov 2006
Posts: 19243
Location: Inside the Matrix
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Hello miaoluzeng and welcome to the forums,
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| but as i know the hierarchic database is a kind of relational database |
No, it is not. Relational concepts may be used when the tables are designed, but the underlying engine is not relational (and is not meant to be).
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| as a pgmer i do not want and need to know the physical operation |
If you intend to be a productive ims programmer, you do. One of the reasons that ims has such high performance is that there is the ability to specifically direct the processing flow at a lower level.
There may be some add-on products that provide some sql front-end, but i'll let those more deeply versed in ims tools reply. |
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Devzee
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Joined: 20 Jan 2007
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Location: Hollywood
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SQL is not available for IMS.
If you dont want to write IMS calls, then you have to develop some IO routines and give it to other programmers including you which will allow you not to worry about the IMS calls.
There are some 3rd party tools like Telon with IMS. |
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miaoluzeng
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Joined: 29 Aug 2007
Posts: 10
Location: CHINA
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hi dick scherrer,
thanks a lot for your answer, but i still have troubles about the basic.
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| Relational concepts may be used when the tables are designed, but the underlying engine is not relational (and is not meant to be). |
the internal engine of relational database is not relational,then the hierarchial database engine is not hierarchial?
if yes
how can ims optimize performance？
else
as we know the two types of database:relational and hierarchial,now one is for logical design the other is for physical...i think it is difficult to explain it. |
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miaoluzeng
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Joined: 29 Aug 2007
Posts: 10
Location: CHINA
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| Devzee wrote: |
SQL is not available for IMS.
If you dont want to write IMS calls, then you have to develop some IO routines and give it to other programmers including you which will allow you not to worry about the IMS calls.
There are some 3rd party tools like Telon with IMS. |
hi Devzee,
so in this way some programers manually translate my io to ims calls.but i think the best way is use translation's program(if have). |
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enrico-sorichetti
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Joined: 14 Mar 2007
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Location: italy
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| ...the internal engine of relational database is not relational,then the hierarchial database engine is not hierarchial? |
It would be wise to review Your understandings of databases archtecture
the internal engines are exactly what the name suggests
relational and hierarchical |
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dick scherrer
Moderator Emeritus
Joined: 23 Nov 2006
Posts: 19243
Location: Inside the Matrix
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Hello,
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| the internal engine of relational database is not relational,then the hierarchial database engine is not hierarchial? |
This might make for interesting phylosophical discussion. . . . I'm not sure how it applies to implementing an application.
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| as we know the two types of database:relational and hierarchial,now one is for logical design the other is for physical... |
I believe that we do not all know this - it is bacically not accurate. There are logical and physical aspects of all database applications.
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| i think it is difficult to explain it. |
Things not understood clearly are most difficult to explain 
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| how can ims optimize performance |
A short answer is that ims typically requires far less overhead than DB2. If this is not what you are asking, please clarify. |
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Sandy Zimmer
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Joined: 13 Jun 2007
Posts: 826
Location: Wilmington, DE
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| I need to add my two cents. IMS is the best thing ever invented - it is extremely fast and accurate - it was invented for the first US moon mission. All the major transaction processing banks use it. It also requires some effort to become good at it. |
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Bitneuker
CICS Moderator
Joined: 07 Nov 2005
Posts: 1104
Location: The Netherlands at Hole 19
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| miaoluzeng wrote: |
hi all,
the GU GHU GN GNP call.. is difficult for a relational databaser,but as i know the hierarchic database is a kind of relational database.as a pgmer i do not want and need to know the physical operation,so can any tools or program translate sql to ims calls? |
First the basic question: no..... there's no transalation from sql to ims.
The reason why: the hierarchic database is NOT a kind of relational database. The only relationship is that pfysical IMS databases can be combined into logical databases. The basics however differ very much from the way DB2-tables are joined. A join of a couple of DB2-tables leads to an explosion of intermediate tables. IMS is just hierarchical and uses the index for that. As stated before an IMS programmer is able (in co-orporation with the DBA) to find the most perfect pathcalls in order to use the best calls for a perfect performance. Like Sandy wrote it's a matter of understanding how to access the database. If you don't understand the way IMS works it's hardly no use to try and develop programs in it; unlike DB2 and SQL IMS-programming is an art  |
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miaoluzeng
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Joined: 29 Aug 2007
Posts: 10
Location: CHINA
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hi all,
it found some tools depand on my mind,
it can use sql->websphere->ims.
let's see www.ibm.com/developerworks/db2/library/techarticle/dm-0504zikopoulos/
"DB2 Connect can to deliver transparent access to other data sources such as Oracle, Microsoft SQL Server, Sybase, IMS, VSAM, and a whole host of other data sources."
before i found this, i just think we can use pgm to translate sql to imscalls and the pgm just needs parse DBD and SQL sentence.maybe someone had developed it yet, so i write the topic. |
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Sandy Zimmer
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Joined: 13 Jun 2007
Posts: 826
Location: Wilmington, DE
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| Have you tried to use it? |
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miaoluzeng
New User
Joined: 29 Aug 2007
Posts: 10
Location: CHINA
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no,i have no chance to use it and no one knows it around me,so bad  |
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