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SQL Server Databases (SQLServer,Oracle,DB/2

On Mon, 28 Dec 1998 07:48:00 GMT, "Paul Nichols"

Quote
<pauln...@bhm.bellsouth.net> wrote:
>I have noticed several people asking questions about TTable Connections and
>SQL Databases. For your information, I wanted to share with everyone why YOU
>DO NOT WANT TO USE TTABLES with SQL-Databases.

Well, I've been telling anyone who will listen to use TTables with SQL
databases, so I should probably explain my position.  I don't trust the
manuals too far on this; my partner and I have experimented extensively
to find how to get acceptable performance from SQL servers.  We've
worked mostly with MS SQL Server and Sybase SQL Anywhere, both through
ODBC (I'm too cheap to buy Delphi C/S), and our results may be not be
valid for other arrangements.  Given the lack of definitive information
on the subject, I'd advise anyone who is really concerned about the
question to do their own experiments and draw their own conclusions.

Quote
>1) TTables do not produce efficient SQL code. [They give you all data on a
>table and are terribly inefficient].

Live queries are no better.  The BDE rewrites live queries to return
*all* the columns from the underlying table.  You may think you asked
for SELECT JustTheKey FROM TheTable, but the server got a request to
SELECT * FROM TheTable (actually it got a request with all the table
columns enumerated).  If you want to limit the columns returned from a
SELECT, you can create a view on the server and connect a TTable or a
TQuery to it, or create a stored procedure and connect a TQuery or a
TStoredProc to it.

Limiting the rows returned by a TTable with a filter string is also
efficient.  The TTable will reissue the SELECT with the filter as part
of the WHERE clause.  Filtering with an OnFilterRecord event handler is,
of course, done locally.  Filtering with SetRange works exactly like the
Filter property.

Quote
>2) TTables can produce locks on data tables.

How?  The servers we're dealing with don't even support record locks
except through some very implementation-specific tricks.  Do the ODBC
tracing and you won't see any of them.

Quote
>3) SQL management is not effected by using TTables.

Um.  I'd argue if I had any idea what you meant.

Quote
>4) Transaction level management is not effected by TTables.

Do you mean transactions are not supported?  Sure they are.  Or if you
mean isolation levels, they are too.

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>5) LiveConnects are dangerous with TTables.

That's a little too nebulous for me to answer.

Quote
>6) TTables are not designed for SQL Access, They are designed for local
>table use.

I don't care very much what they're designed for, just what they *do*.
We've been faced with trying to explain to customers why they can't have
even a fraction of the interactive performance from expensive
client-server applications that they're used to from their old
DOS-based, Dbase-tabled applications.  Why should scrolling to the end
of a 10,000 record dataset take 15 seconds and 10 megabytes of local
memory?  Why can't they do incremental searches in that dataset?

And those 10 megabytes of local storage are holding data that had to be
retrieved by the server and transferred over the network.  Neither of
those is helping performance.

Quote
>7) Joins by using Master-Detail TTables are terribly inefficient.....

Not at all.  They simply reissue the SELECT with an appropriate WHERE
clause.

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>In case you wonder if I am correct, look in the Borland manuals. They will
>back up what I am saying.

No, don't look at the manuals.  Do the tests and look at the results.

Quote
>TQuery was designed for SQL-databases, as was TUpdateSQL, and TStoredProcs.
>Please use TQuery Statments when connecting to SQL Databases and also use
>StratTransactions, Commits, and Rollbacks for consistent control.

But TTables support transactions and cached updates too.

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Re:SQL Server Databases (SQLServer,Oracle,DB/2


Quote
David Rifkind wrote in message

<3687b6ec.1914...@netnews.worldnet.att.net>...

Quote
>On Mon, 28 Dec 1998 07:48:00 GMT, "Paul Nichols"
><pauln...@bhm.bellsouth.net> wrote:
>>I have noticed several people asking questions about TTable Connections
and
>>SQL Databases. For your information, I wanted to share with everyone why
YOU
>>DO NOT WANT TO USE TTABLES with SQL-Databases.

>Well, I've been telling anyone who will listen to use TTables with SQL
>databases, so I should probably explain my position.  I don't trust the
>manuals too far on this; my partner and I have experimented extensively

Kind of scary to see a posting like this. Who is right?

Robert

Re:SQL Server Databases (SQLServer,Oracle,DB/2


On Tue, 29 Dec 1998 16:25:17 GMT, "Robert Kaplan" <rkap...@iamerica.net>
wrote:

Quote

>David Rifkind wrote in message
><3687b6ec.1914...@netnews.worldnet.att.net>...
>>On Mon, 28 Dec 1998 07:48:00 GMT, "Paul Nichols"
>><pauln...@bhm.bellsouth.net> wrote:
>>>I have noticed several people asking questions about TTable Connections
>and
>>>SQL Databases. For your information, I wanted to share with everyone why
>YOU
>>>DO NOT WANT TO USE TTABLES with SQL-Databases.

>>Well, I've been telling anyone who will listen to use TTables with SQL
>>databases, so I should probably explain my position.  I don't trust the
>>manuals too far on this; my partner and I have experimented extensively

>Kind of scary to see a posting like this. Who is right?

The one who's taller, of course.  Don't you follow politics?  By the
way, I'm 6'6". [*]

[*] No, I'm not.

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Re:SQL Server Databases (SQLServer,Oracle,DB/2


It's difficult to accept unsubstantiated hyperbole. Substantiated hyperbole
is much more fun...

Shaun McArthur

Quote
Robert Kaplan wrote in message ...

>David Rifkind wrote in message
><3687b6ec.1914...@netnews.worldnet.att.net>...
>>On Mon, 28 Dec 1998 07:48:00 GMT, "Paul Nichols"
>><pauln...@bhm.bellsouth.net> wrote:
>>>I have noticed several people asking questions about TTable Connections
>and
>>>SQL Databases. For your information, I wanted to share with everyone why
>YOU
>>>DO NOT WANT TO USE TTABLES with SQL-Databases.

>>Well, I've been telling anyone who will listen to use TTables with SQL
>>databases, so I should probably explain my position.  I don't trust the
>>manuals too far on this; my partner and I have experimented extensively

>Kind of scary to see a posting like this. Who is right?

>Robert

Re:SQL Server Databases (SQLServer,Oracle,DB/2


Quote
news.ciaccess.com wrote in message <368a7d9...@news.wincom.net>...
>It's difficult to accept unsubstantiated hyperbole. Substantiated hyperbole
>is much more fun...

>Shaun McArthur

TQUERY YESTERDAY, TQUERY TODAY, TQUERY FOREVER!!!!

Robert

Quote

>Robert Kaplan wrote in message ...

>>David Rifkind wrote in message
>><3687b6ec.1914...@netnews.worldnet.att.net>...
>>>On Mon, 28 Dec 1998 07:48:00 GMT, "Paul Nichols"
>>><pauln...@bhm.bellsouth.net> wrote:
>>>>I have noticed several people asking questions about TTable Connections
>>and
>>>>SQL Databases. For your information, I wanted to share with everyone why
>>YOU
>>>>DO NOT WANT TO USE TTABLES with SQL-Databases.

>>>Well, I've been telling anyone who will listen to use TTables with SQL
>>>databases, so I should probably explain my position.  I don't trust the
>>>manuals too far on this; my partner and I have experimented extensively

>>Kind of scary to see a posting like this. Who is right?

>>Robert

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