Question: What can I use to produce VRML, or can I write it like HTML? Answer: It is possible to write VRML as a purely text-based language, using a regular

Question: [Joe Celko’s Sales Gaps Puzzle]Given a table “sales” and a column “saledate” and “customer,” is there a way to get the average number of days between sales dates for

Question: [Joe Celko’s Quantity on Hand Puzzle]You are now the guy in charge of the company inventory. You get requisitions that tell how many widgets people are putting into a

Question: [Joe Celko’s Reservations Puzzle]Since I spend a lot of time this column talking about problems with the order of execution of SQL statements, it is only fair that I

Question: I’ve heard a lot about VRML, but don’t know what it is. Please explain. Answer: VRML (Virtual Reality Markup Language) is a method for sending 3D data across the

Question: [Joe Celko’s Equal Sets Puzzle]Set theory has two symbols for subsets. One is a “horseshoe” on its side, which means that set A is contained within set B and

Question: [Joe Celko’s Dataflow Diagrams Puzzle]Tom Bragg posted a version of this problem on the CASE Forum on CompuServe. You have a table of dataflow diagrams (DFDs), which has the

Question: [Joe Celko’s Milestones Puzzle]This puzzle, in a little different form, came from Brian Young. His system tracks a series of dates (milestones) for each particular type of service (tos)

Question: We are putting together a book with contributions from many Anthologies (identified by their contrnum). We want to find all Anthologies thathave articles in exactly two out of three

Question: How would I change the following statement to yieldonly unique values? select * FROM WEBDBASE where ST = ‘#State#’ AND #SPECIALTY# = ‘x’; Answer: You can’t get unique values

Question: How can I use SQL to specify a query like the example below: select * from mytable where column like ‘a[bc]’This should match both “ab” and “ac” but not

Question: How do I arrange to sort within a GROUP BY clauserather than over the complete result set, e.g. L0 PDV …… L90 PDV …… L180 PDV …… L270 PDV

Question: [Joe Celko’s Employment Agency Puzzle]You are running an employment agency that has requests for jobs and applications from candidates. Both of these forms include a list of the skills

Question: [Joe Celko’s Personnel Problem Puzzle]Daren Race was trying to aggregate the results from an aggregate result set using Gupta’s SQLBase and could not think of any way other than

Question: [Joe Celko’s Consultants Puzzle]Brian K. Buckley posted a version of the following problem on the PowerSoft CompuServe forum in the WATCOM SQL section in 1994 November requesting assistance. He

Question: [Joe Celko’s Budget Versus Actual Puzzle]C. Conrad Cady posted a simple SQL problem on the CompuServe Gupta Forum. He has two tables, Budgeted and Actual, which describe how a

Question: [Joe Celko’s One In Ten Puzzle]Alan Flancman ran into a problem with some legacy system data that had been moved over to a SQL database. The table looked like

Question: Let’s say I have two tables, one with the columns PositionIDand SkillID and one with the columns EmployeeID and SkillID.If I do a SELECT SkillID FROM First_Table WHERE PositionID=7,I

Question: Is there a quick and dirty way to export a delimited datasetvia a simple query? I would like to get something like: value1,value2,value3(The delimeters could be commas, semi-colons, etc.)

Question: The Situation: I need to define some queries to extract data from an existing database (I am using MS Access 2.0). It consists of only two tables, from which

Question: What are the common uses of stored procedures? Answer: Many databases use stored procedures and/or triggers to implementreferential integrity [ensuring that data referenced by another tabledoesn’t get deleted or

Question: I’ve got a “new user” question for you. Some of the tables in our databaseshave several columns containing data that’s not used very often. When I’musing ad-hoc queries, it

Question: What are some of the new features of Power Objects Version 2? Answer: The major new features of Version 2.0 include:New platforms – OPO will continue to support both

Question: I want to let the user select more than one row in a repeater so my application can act on all of them at one time? Answer: A repeater

Question: When I open a session to my Oracle database, I can only see tables that are owned by my user name. How can I get to see other public

Question: I want to have a form that does not appear in a MDI (multiple document interface) frame. Can I do this? Answer: In Version 2 of Power Objects, you

Question: I want to use a string variable with the date in it (format would be 02/22/96). How do I accomplish this? Answer: You’ll need to first convert the date

Question: What is Embedded SQL, and howis it used with the C language? Answer: As the name implies, Embedded SQL describes SQL statements that are embedded in a host language.

Question: I need to query a database with outer joins on more thanone table, and am finding that my database doesn’t support it.Is there any way to work around the

Question: I am doing a select from a table where I want to combine two fields. Specifically, I have the StreetNumber andthe StreetName stored separately. I would like to beable