Creating Queries

Don't be afraid of large joins—learn to generate complex SQL queries from easy-to-use interfaces.
Conclusion

While it is tempting to give users infinite freedom to enter information into a web site, it is usually best to limit their inputs as much as possible. Creating simple HTML-based query generators is not difficult and can even be easy once you get the hang of it. The trick is to formulate queries in such a way that the user can get the maximum information while knowing as little as possible about the underlying database. Even when the queries are easy to create, finding ways to turn those queries into language suitable for non-programmers can be a challenge.

Resources

Reuven M. Lerner , an Internet and Web consultant, moved to Modi'in, Israel following his November marriage to Shira Friedman-Lerner. His book Core Perl will be published by Prentice-Hall in the spring. Reuven can be reached at reuven@lerner.co.il. The ATF home page, including archives, source code and discussion forums, is at http://www.lerner.co.il/atf/.

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Hi Friends, I am working on

Anonymous's picture

Hi
Friends,
I am working on USB OHCI 1.1. driver on pxa27x. The kernel i am using is 2.6.10 that come up with ohci-pxa2x7x code.

I am using only port 1.
The problem arise when driver code gives reset to port 1 (BY SETTING 1 TO UHCRHPS1[PRS]). This reset in turn should enable the port UHCRHPS1[PES](make it 1) , but its not doing that and it also showing UHCRHPS1[PRSC]=1 (port reset complete), UHCRHPS1[CSC]=1 (connect status change), UHCRHPS1[PESC]=1 (port enable status change).

The following is the error that i am facing.

"hub 1-0:1.0: Cannot enable port 1. Maybe the USB cable is bad?"

I am using per port power mode. Its also not showing overcurrent condition for port 1.
The following are the status of registers while this error occured.

UHCREV = 10
UHCHCON = 83
UHCCOMS = 0
UHCINTS = 44
UHCINTE = 8000001a
UHCINTD = 8000001a
UHCHCCA = a03e5000
UHCPCED = 0
UHCCHED = 0
UHCCCED = 0
UHCBHED = 0
UHCBCED = 0
UHCDHEAD = 0
UHCFMI = 27782edf
UHCFMR = 2dc
UHCFMN = 1656
UHCPERS = 2a2f
UHCLST = 628
UHCRHDA = 4000902
UHCRHDB = e0000
UHCRHS = 8000
UHCRHPS1 = 130301
UHCRHPS2 = 8
UHCRHPS3 = 8
/*--non ohci registers*/
UHCSTAT = 0
UHCHR = 44
UHCHIE = 2080
UHCHIT = 0

If anybody might come across such problme or anybody has some idea about it, then please share your idea.

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