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Groups > comp.lang.java.programmer > #36046

Re: Scaling java app

From Arne Vajhøj <arne@vajhoej.dk>
Newsgroups comp.lang.java.programmer
Subject Re: Scaling java app
Date 2016-12-02 22:51 -0500
Organization Aioe.org NNTP Server
Message-ID <o1tfgm$n67$1@gioia.aioe.org> (permalink)
References (15 earlier) <o1q5i3$ad6$1@jstuckle.eternal-september.org> <o1qogr$jvg$1@gioia.aioe.org> <o1s49a$fc6$1@jstuckle.eternal-september.org> <o1tcab$jo0$1@gioia.aioe.org> <o1tens$ns8$1@jstuckle.eternal-september.org>

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On 12/2/2016 10:40 PM, Jerry Stuckle wrote:
> On 12/2/2016 9:57 PM, Arne Vajhøj wrote:
>> On 12/2/2016 10:35 AM, Jerry Stuckle wrote:
>>> On 12/1/2016 10:07 PM, Arne Vajhøj wrote:
>>>> On 12/1/2016 4:45 PM, Jerry Stuckle wrote:
>>>>> It's more than just inertia.  It's because COBOL has packed decimal
>>>>> format, which is directly compatible with major databases DECIMAL
>>>>> data type.
>>>>>
>>>>> Packed decimal on the mainframes is good to 31 significant digits by
>>>>> default (there are libraries to extend that), although in most cases
>>>>> only 18 to 20 are required.
>>>>
>>>> Most languages support fixed point math today.
>>>>
>>>> Java got BigDecimal with arbitrary precision. .NET languages got decimal
>>>> with 95 bits of precision. C++ got various libraries (may be a little
>>>> bit cumbersome, but not more than it can be made working).
>>>>
>>>> The support for fixed point data types has not been a good reason
>>>> for COBOL for 15-20 years.
>>>
>>> But is it compatible with the DECIMAL data type on databases?  Can you
>>> *efficiently* read and write DECIMAL types to DB2,  instance?
>>
>> JDBC (which will be below practically all relational database usage
>> in Java) supports DECIMAL/BigInteger the same way as any other datatype
>> like INTEGER/int or VARCHAR/String.
>>
>> Somewhat similar for ADO.NET, .NET and decimal.
>
> Yes, and those are very inefficient when dealing with DECIMAL datatypes.

They transfer as fine as any other data type.

All operations on them work. One meed to accept method calls instead
of operators, but that is manageable.

>>> And exactly how does Java interface efficiently with databases like DB2?
>>
>> In practice the type 2 or the type 4 JDBC driver.
>>
>> In theory it could also be SQLJ. But I have never met a living person
>> that has used SQLJ.
>>
>
> Which is still less efficient than the native calls.

It uses the same mechanisms as embedded SQL in other languages
including COBOL.

>>>                                           where every SQL statement
>>> must be interpreted by the database.
>>
>> Usually the execution plan will be cached in the database.
>>
>
> "Usually".  Not always.  And for how long?

It all depends on the database.

A lot of databases purge when they need to free memory, so if there
is memory available, then it will stay to the database is restarted.

>>>                                    Additionally, the connection to
>>> the database is relatively slow.
>>
>> The connection speed must depend more on the physical connection
>> than on what software is doing the connect.
>>
>
> In your PCs, yes.  Not true on mainframes (and hasn't been for at least
> 40 years).  Multiple fiber optic channels transferring data concurrently
> via DMA, disks with transfer rates as good or better than SSDs on PCs,
> huge caches on the disk controllers... I/O transfer rate is where
> mainframes excel.

Speed between database and storage does not matter much for connection
speed. That depends more on the speed between the application and the
database.

But even if that was not the case, then it just determines whether
connection is fast or slow - it does not make connection speed
different between different types of connects.

Arne

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Thread

Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-21 11:06 -0600
  Re: Scaling java app Martin Gregorie <martin@address-in-sig.invalid> - 2016-11-21 19:48 +0000
    Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-21 12:33 -0800
      Re: Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-21 18:23 -0600
        Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-21 21:22 -0500
          Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-21 21:25 -0500
            Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-21 22:29 -0500
              Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-21 22:41 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-22 10:51 -0500
          Re: Scaling java app a.laforgia@gmail.com - 2016-11-23 04:58 -0800
            Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-23 05:18 -0800
              Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 09:52 -0500
                Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-23 07:51 -0800
            Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 09:46 -0500
              Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-23 08:07 -0800
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 12:10 -0500
                Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-23 10:39 -0800
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 14:57 -0500
            Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-23 15:04 -0500
              Re: Scaling java app a.laforgia@gmail.com - 2016-11-24 02:01 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-24 09:10 -0500
                Re: Scaling java app a.laforgia@gmail.com - 2016-11-25 03:48 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-25 09:58 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-25 10:22 -0500
              Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-25 10:34 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-26 00:01 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-26 09:05 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-26 09:52 -0500
  Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-21 19:46 -0500
    Re: Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-21 21:12 -0600
      Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-21 22:44 -0500
        Re: Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-22 09:56 -0600
          Re: Scaling java app Silvio <silvio@internet.com> - 2016-11-22 20:07 +0100
            Re: Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-22 18:00 -0600
              Re: Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-22 19:35 -0600
              Re: Scaling java app Silvio <silvio@internet.com> - 2016-11-24 00:51 +0100
          Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 10:26 -0500
            Re: Scaling java app Eric Sosman <esosman@comcast-dot-net.invalid> - 2016-11-23 15:54 -0500
              Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 20:46 -0500
          Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 12:00 -0500
            Re: Scaling java app Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2016-11-23 19:53 -0600
              Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 21:21 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-23 21:34 -0500
                Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-28 05:06 -0800
                Re: Scaling java app Richard Maher <maher_rjSPAMLESS@hotmail.com> - 2016-11-24 20:45 +0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-24 09:12 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-25 10:32 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-26 00:05 -0500
                Re: Scaling java app Martin Gregorie <martin@address-in-sig.invalid> - 2016-11-26 15:24 +0000
                Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-11-28 05:08 -0800
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-28 19:51 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-28 21:18 -0500
                Re: Scaling java app lewbloch@gmail.com - 2016-11-29 13:50 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-29 16:53 -0500
                Re: Scaling java app lewbloch@gmail.com - 2016-12-01 13:27 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-01 16:45 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-01 22:07 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 10:35 -0500
                Re: Scaling java app Gene Wirchenko <genew@telus.net> - 2016-12-02 08:53 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 15:05 -0500
                Re: Scaling java app Martin Gregorie <martin@address-in-sig.invalid> - 2016-12-02 20:25 +0000
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 16:20 -0500
                Re: Scaling java app Martin Gregorie <martin@address-in-sig.invalid> - 2016-12-02 18:33 +0000
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 15:16 -0500
                Re: Scaling java app Martin Gregorie <martin@address-in-sig.invalid> - 2016-12-02 22:57 +0000
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 19:25 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 22:18 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 22:28 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 22:36 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-03 11:27 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 22:05 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 22:30 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 22:41 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-03 11:29 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 22:00 -0500
                Re: Scaling java app lewbloch@gmail.com - 2016-12-02 11:40 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 15:17 -0500
                Re: Scaling java app lewbloch@gmail.com - 2016-12-02 16:26 -0800
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 20:46 -0500
                Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-12-02 12:44 -0800
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 21:57 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 22:40 -0500
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 22:51 -0500
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-03 11:42 -0500
                Re: Scaling java app Andreas Leitgeb <avl@logic.at> - 2016-12-02 15:43 +0000
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-12-02 21:19 -0500
                Re: Scaling java app Martin Gregorie <martin@address-in-sig.invalid> - 2016-12-02 10:28 +0000
                Re: Scaling java app Jerry Stuckle <jstucklex@attglobal.net> - 2016-12-02 10:37 -0500
                Re: Scaling java app Gene Wirchenko <genew@telus.net> - 2016-12-02 09:00 -0800
                Re: Scaling java app Eric Douglas <e.d.programmer@gmail.com> - 2016-12-01 13:50 -0800
                Re: Scaling java app Arne Vajhøj <arne@vajhoej.dk> - 2016-11-25 10:30 -0500
  Re: Scaling java app Roedy Green <inquiry@mindprod.com> - 2016-11-27 16:42 -0800

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