SQL Challenge: Dynamically producing a tag cloud for World Cup Football matches

Lucas Jellema June 22, 2014 Database, SQL No Comments

Tag clouds are a special way to present information about a set of records. Tags are descriptive labels that are associated with specific records. A tag cloud visualizes the …

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Oracle SQL – Finding free adjacent seats in an airplane, using Subquery Factoring, Analytical Functions (LISTAGG and LEAD), Outer Join, PIVOT and good old INSTR

Lucas Jellema March 4, 2013 Database, Oracle 1 Comment

Using Oracle SQL to resolve meaningful and slightly less serious challenges is one of my favorite (semi-)professional pastimes. In the last two weeks, I have been presenting on various …

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Producing simple Pie Chart straight out of the Oracle Database – leveraging dbms_epg, CANVAS, LISTAGG and some JavaScript

Lucas Jellema June 13, 2011 Database, Databases, Oracle, PL/SQL, Web HTML5 CSS3 No Comments

Once upon a time, I had something of a reputation for creating Charts in SQL. Bar Charts, Pie Charts, Gantt Charts and several other unlikely chart types, all created …

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Anti-Search patterns – SQL to look for what is NOT there – Part One

Lucas Jellema December 20, 2010 Database, IT, Java, Oracle 4 Comments

Usually in SQL queries, you will try to retrieve information from a database by reading specific records from the relevant tables. However, there are situations where what you want …

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Tag: listagg