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Practical Databases tutorials, troubleshooting notes and implementation guides from real projects.
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Practice makes perfect. Or in my case, any practice is a start. This article serves as a quick note on how to use regular expressions within SQL statements: How? For the following examples, I am pretending to select rows from a table called `STUDENTS`.
This article is to remind me how to create a blank weekly timesheet which reads the duration of events from a database and auto-completes your timesheet.
A quick note on how I got round one this one.
A quick article on how to compare two Microsoft databases using the tools provided with SQL Server and without having to download any third-party products.
Quick note on how to do this. I was tasked with cleaning up an english database by replacing all special alphabets (ë to e) and non-alphanumeric symbols with URL friendly characters. How? -- return all records that contain non-alphanumeric characters SELECT * FROM myTable WHERE myColumn NOT REGEXP '^[A-Za-z0-9]+$'...
This is a quick article on how to split a single row into multipe rows based on the value of a column in the same table.
So this is a quick note to myself as I was playing with the relevance heuristics of a query. This example adds a column of relevance and sorts the rows accordingly. How? This has to be a real quick one for a dropdown search field which has to find relevant terms to autofill/autocomplete a search form: -- where @ThisSea...
This is an article to remind me how to modify a column in a database table the old fashioned way (as in stop making me use GUI interfaces so poorly programmed when even I've made better DBMS tools). All SQL -- Add a column to an existing table (giving it datatype char(2) and allowing NULL) ALTER TABLE myTable ADD myCol...
Just a quick note to myself on how to reorder columns as I was having difficulty using a phpMyAdmin interface to do this. How? Taken from the best forum for programming Qs&As: http://stackoverflow.com/questions/4095481/easy-way-to-re-order-columns Method: phpMyAdmin So in the phpMyAdmin interface, apparently, you can d...
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This site exists as a practical knowledge base built from real-world experience across systems, platforms, and technologies since 1999. Much of the content documents solutions, edge cases, and working patterns that were learned through investigation where documentation was incomplete or absent, and is shared to reduce the same friction for others.
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