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Sorting “Codes” within a Column

Question: I have a table that consists of numbers stored as characters.How can I sort them in numerical order? I can’t convert thisfield to numeric because some content is alpha

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Solving Multiple Conditions Within a Group

Question: [Joe Celko’s Work Order Puzzle]Cenk Ersoy asked this question on the Gupta Forum on CompuServe. He has a table that looks like this: CREATE TABLE Projects (workorder CHAR(5) NOT

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INSERT INTO Syntax

Question: What is the standard SQL-92 syntax for INSERT INTO? Answer: Be sure to check your product documentation for any variations! This is standard syntax, but not all products will

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What is GMD’s Dynamic Worlds proposal about?

Question: Please explain Dynamic Worlds. Answer: “The Power of Dynamic Worlds” proposal from the German National Research Center (GMD) is based on an interaction model developed for collaborative distributed virtual

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Why won’t my VRML browser work with 2.0?

Question: I went to see one of the new VRML 2.0 sites, but only sawblackness. What is going on? Why won’t my VRML browserwork with the new version? Answer: Just

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What is Microsoft’s Active VRML proposal about?

Question: What are the key features of Active VRML? Answer: Microsoft’s Active VRML, is a proposal built on top Microsoft’s Direct X suite of graphics/multimedia APIs, and also incorporates Microsoft’s

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How compatible are VRML browsers?

Question: If I make a VRML page, can it be read by any browser? Answer: The original idea behind VRML 1.0 was that any VRML scene should be viewable using

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Finding the Top n Within a Group

Question: [Joe Celko’s Best Salesmen by Territory Puzzle]Martin Tillinger posted this problem on the MSAccess forum of CompuServe. How do you get the top three salesmen in each territory, given

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How can I create VRML pages?

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

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Finding the Greatest Lower Bound

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

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Calculating Running Totals

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

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CHECK Constraint To Avoid Overlapping Data

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

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What is VRML?

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

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Finding Two Equal Sets of Data

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

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Dataflow Diagrams

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

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Pivoting Table Data — Horizontal Display

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)

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Finding Exactly Two of Three — Conditions

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

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Finding Unique Data

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

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Pattern Matching

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

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GROUP BY: Sorting with an Additional Column

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

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Matching Employees’ Skills with Jobs

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

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Calculating Hourly Billings

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

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Compare Budget and Actual Tables

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

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Finding Exactly One Non-Zero Column

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

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Delimited Data

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.)

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Finding Only the Most Current Row

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