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Question: I’ve heard a lot of talk about “client-server architecture” ? is it something real, or just marketing hype? Answer: Indeed, client-server architecture is real. Put simply, the client-server model
Question: What is the OnKey() method? Answer: The OnKey() method is a new method introduced with OPO version 1.0.16. The OnKey() method is triggered for an object whenever a user
Question: When I open a session to an Oracle database, I can’t see any tables other than those owned by my user name. How can I get access to tables
Question: Can an OPO application act as an OLE client and use OLE automation with an OLE server? Answer: OPO Version 2.0 can act as an OLE server, but not
Question: I want to use a unique compound key, with a string columns and a numeric column, in my table. Since Blaze does not support compound keys, I will have
Question: Whenever I try to reference an object in a repeater, I get an error message telling me that “Repeated control can be used only in aggregation function”. How can
Question: How do I open up a blank form – a form without any values displayed? Answer: As you probably know, you can add a DefaultCondition to your form, such
Question: I am using the EXEC SQL command to insert some data into a database on the CommitForm()method of a form, but the data is not showing up in the
Question: When a user selects a value from a list box, I populate the contents of arepeater. I also want to set the focus into the repeater’s first field.How can
Question: How can I define a function that is not associated with a particular form? Answer: You can define an function that is not associated with a particular form by
Question: When I set the FormatMask property for a data field object, the value of the field is formatted when a user enters data and tabs out of the field.
Question: I want to use many instances of a class in my form, but can’t seem to figure out an easy way to check on the status of all the
Question: Is there a way to send mail with a mouse click? I’m working on a Mac and in Windows. Answer: You can send mail, or do virtually anything else
Question: I have an employee table with a field empno (employee number) and an hours table that contains all time that is worked by all employees.The hours table has the
Question: I’ve been trying to construct a query on the databaseto see if the value in a particular field matches a long list of correct answers. For example, I would
Question: How do I create a column with a row ID that adjusts if a row is deleted?That is, if I had numbers 1,2,3,4,5,6 and I delete record 3, record
Question: I am trying to write a report that will bring back fiveindividual pieces of data that are stored within the same column in a table. How do I do
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