Re: SQL very fast here & very slow there

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At 16:43 24/01/2003 24/01/2003, John A DAVIS wrote:
We had a very sluggish SQL Server 7.0 and we tested the RAM chips and found one to be bad. It was throwing off a whole bank of chips (1gb). Stuff is a lot faster now.
Also, your indexes might be different on your tables. Indexing the correct fields, especially the joined fields and ID fields used in searches, really helps big time.
I'm no expert.
At 16:32 24/01/2003 24/01/2003, Brent Baisley wrote:
I'm not sure how Paradox works, but it may be locking problems you are running into. I know Paradox used to have issues with data changing while a query was executing. On your home machine you are the only one accessing the DB, so there wouldn't be any contention. Your home DB probably hits the cache since the data isn't changing.
How busy is the DB at school?
Thanks a lot for your suggestions; sometimes Paradox does have locking problem ... but the DB at school is not very busy, and the tables and web pages I am using are still private, in a password protected area. Indexes are identical So I'm still in doubt. I have checked RAM and indexes at school but everything seems Ok.

And I've found something even more strange: I've splitted the SQL query in two: the first uses just the first two tables, and the output table is then visited with a PhP while {} loop which at every step execuste a simple SQL SELECT on the third table; I thought this a much less efficient method to make the web page, and so it is on my home PC, where it takes some 3 or 4 seconds to complete (instead of 1 sec or less); but on the school server the web page takes "only" 15-20 sec, a lot less than before (60sec and even more)! A 3 tables join is too much for the server??

So I've found a (not so good) solution to the problem, but I still do not understand it's nature and this is quite disappointing.

There is really nothing in your question applicable to PHP. Have you tried a Paradox list?
I'll try, but using the Paradox 9 program the SQL Select executes in a flash at home and at school, there is no measurable difference; maybe the problem is with the ODBC Paradox driver?


Paolo Bonavoglia
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