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Question: What is the syntax to get a series of “counts” on a table? An exampleof what I am trying to do is as follows:SELECT col1 = COUNT(tstfield1=’X’),col2 = COUNT(tstfield2=’Y’)
Question: I’m wondering whether it would be faster to join a large table to a small table by placing the large table on the left side or theright side of
Question: I have two related tables. I need to go and update atable searching for a value I find in the second table (byjoining both tables). I wrote the following
Question: I have been having a lot of trouble with a SqlLookup() function. Whenever I use a WHERE clause, I get a parse error.The offending WHERE clause is “WHERE SW_LICENSE
Question: How are transactions handled in OPO? Answer: Transactions are the core of multi-user data processing integrity. A transaction defines an all-or-none unit of work. The classic example of a
Question: Data field objects in OPO can accept any amount of data, but if I send too many characters to the server, I get an error “flushing the row to
Question: We have several heavily-used tables with lots of columns (average around 30 columns), and the users are getting locked out frequently. We’ve thought about splitting the tables, but didn’t
Question: Our system is experiencing several lock conflicts. We’ve got a consultantlooking at the details, but I was hoping you could explain what’s going onbehind the scenes when records are
Question: What are the differences between LEFT, RIGHT, INNER and OUTER JOINS? Answer: An INNER JOIN is the most common type: It combines all the data from the tables specified
Question: I have nine offices. I want each office to connect across aWAN and run client/server applications with all datacontained on one central server. However, we are finding the delays
Question: What are the advantages/disadvantages of putting large binary files (1+ MB) in BLOB columns versus storing them on a file server with a reference such as a directory/file spec
Question: I want to periodically check to see if a user’s database connection has been lost. How can I? Answer: First of all, a solution. You can implement periodic ‘polling’
Question: The repeater in my application seems to be very slow in populating. Is there anything I can do to improve its performance? Answer: Poor performance can be the result
Question: I’ve heard several of the arguments in favor of a server that supports datareplication. What are the potential problems? Answer: For our readers, the advantages of data replication [creating
Question: My applet draws lines. I click at the place where I want my line to start and then I click at the end of it. It draws a line
Question: How can I get the display value of a list box? Answer: In Oracle Power Objects, the Value property of the list box isautomatically set to the internal value
Question: Can you help me complete the enclosed program? A “Factorial Method”must be written. /////// File: Factorial.java /////// class Factorial { /* put factorial method here */ public static void
Question: I am currently writing an application to scan a text file for certain text keywords, and then copy the text (in between the kewords) into a new textfile. Could
Question: I am attempting to implement an applet that needs multipleframes (windows) that all belong or work under a single frame ? sort oflike an MDI application. However, each of
Question: I want to retrieve data from a database that is not associated withany objects on a form. How do I do this? Answer: A recordset is a client-side mechanism
Question: How do I limit the rows retrieved for a Power Objects report? Answer: The QueryCondition() method is not called when a report is executed,so you can only set a
Question: It isn’t clear to me how to do ‘smart’ painting. For example, ifI want to paint only a portion of something, what should I do?There are paint/repaint methods that
Question: How can I dynamically add or delete entries from a list box, popuplist or combo box? Answer: List boxes, popup lists and combo boxes all use the Translationproperty. The
Question: How do I send e-mail from Java? Do I have to open a socket to a specific port on my server (and if so, which port and what should
Question: I have a cancel pushbutton with the IsDismissBtn property set toTrue. When I first created the form, the push button dismissed theform. I added some code to prompt the
Question: I’m writing an MDI application that has two documents. One of the documents has multiple views, which are implemented as FormViews. Several views for the same document can be
Question: How can I convert a String type value to an integer or float?For example,String str=”155.230″;float real;real = str.HowCanIConvert???????; I’ve tried it like this:Integer aValue = new Integer(String.valueOf(“1”)); But this
fld.SetFocus() but it doesn’t work. Any suggestions?
Question: I’m using OPO 1.0.16 on a Mac, and want to confine all input to afield on a form. The user can change some popups on the form, but thecursor
Question: How can I let a user enter a password and hide the charactersentered? Answer: You can let the user enter characters into a field and replace theletters entered by
Question: I posted this question to Java newsgroups, but the response from experts avoids the real issue. Simple applet: import java.applet.*; import java.awt.*; public class FirstApplet extends Applet { public