Level Extreme platform
Subscription
Corporate profile
Products & Services
Support
Legal
Français
Help with SQL select and combining cursors/tables
Message
From
04/10/2001 22:45:25
Peter Brama
West Pointe Enterprises
Detroit, Michigan, United States
 
 
To
04/10/2001 12:10:58
Cetin Basoz
Engineerica Inc.
Izmir, Turkey
General information
Forum:
Visual FoxPro
Category:
Databases,Tables, Views, Indexing and SQL syntax
Miscellaneous
Thread ID:
00563768
Message ID:
00564603
Views:
16
Actually, 2 hours is nothing. My first incarnation of this program, the same routines would take (estimated of course) 6 1/2 days to process. Two hours was a HUGE improvement. Now, the 3-4 minutes for the new selects with joins is much much better. All I have to do now, the current problem, is combine the 3 selects into one then combine that with the original BM table.

>2 hrs ??? Actually I even don't expect it to take 6 mins with scan..endscan approach. SQLs use empty() which is not optimizable (I assume you had indexes on left(zip,5) and other - you might replace the !empty(trim(sddmdata.sdaddr)) expression with :
>!(sddmdata.sdaddr == '') ).
>
>scan approach does one single pass on one of tables (probably you'd want to choose 8500 recs one) and a do case check. It's almost equivalant to one 'optimized' SQL (preparation of indexes might take time - you might even skip that with one table usage with order set to left(zip,5) tag and do some locate while ...for ... But I think indexes + 3 use again would be faster).
>
>You have unnecessary trimming in comparisons. Instead use set ansi and set exact. You might recover extra time doing so too (and possibly you dont need empty() at all).
>Cetin
Peter Brama
West Pointe Enterprises

VFP is getting easier but STILL alot to learn!!
Previous
Reply
Map
View

Click here to load this message in the networking platform