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MySQL Tutorials & Guides

Practical MySQL tutorials, troubleshooting notes and implementation guides from real projects.

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Getting the mysql where in delimited string to work
MySQL

Getting the mysql where in delimited string to work

I have a mySQL database table of room assets that has a field containing the ID numbers of images relevant to this room. The Problem? When I select specifying the statement "WHERE IN (c.RoomImages)", this is interpreted as a string and when converted to a number only retrieves the first value before the first comma. Co...

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MySQL last year week month day trend periods
MySQL

MySQL last year week month day trend periods

Why? I recently made a joomla module that displays the lastest members to signup. It goes a little further and counts activated accounts for the past day, week, month and year (the below examples count all accounts irrespective of being activated or not). It needs to pick up trends as well and compare for example today...

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MySQL parameters in Excel 2007 PivotTables
MySQL

MySQL parameters in Excel 2007 PivotTables

Hopefully the title doesn't put you off but after much Googling and Bing-ing, I still couldn't figure out how to do this. Hopefully this article will help you more than my search engine skills do. My Setup Windows XP Workstation ...needs to open... Excel 2007 SP2 ...with ODBC to... MySQL v5+ ...hosting database... Acti...

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Inserting incremental weeks in MySQL
MySQL

Inserting incremental weeks in MySQL

Situation: I have a silly database table (not mine) storing CMIS Facility week numbers and their starting dates. For those of you unfamiliar with this system, the reason week numbers are different to normal people's week numbers is because these are academic week numbers. So I can't use the built-in functions. The curr...

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MySQL: Find records in one table that are not in another.
MySQL

MySQL: Find records in one table that are not in another.

The Why So I find myself writing increasingly complex SQL scripts and it's at the stage where we need to optimize the queries because some scripts are noticeably slow (as observed by the customer...) and then others not. The What I'm going to run these benchmark tests against a system that is both up and running via th...

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Merge the content of two similar tables in MySQL
MySQL

Merge the content of two similar tables in MySQL

In standard SQL we can combine the contents of two tables with a CROSS JOIN, (BTW these are not instructions to create some table I'll never use again unlike the rest of the solutions I found on the web). In MySQL, I only know how to do this with a UNION ALL clause. Scenario: I have a Joomla module which should take th...

Read note 37,132 hits
Accessing a MySQL Database with Business Intelligence Development Studio
MySQL

Accessing a MySQL Database with Business Intelligence Development Studio

Well I tried the SQL Server Management Studio solution to connect to a MySQL database then lost my way wondering what was I trying to achieve? I've written this article because this is how I connected to a MySQL database from within the Business Intelligence Development Studio (BIDS) IDE from Microsoft. Required: Windo...

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SQL Queries for Statistics
MySQL

SQL Queries for Statistics

Basically, I've started using so much more SQL in our new Business Intelligence projects that I've been revising all my scripts to see what SQL I can optimize. One of my systems is a MediaWiki CMS which is used for the official Bournemouth University Knowledge Base. The skin itself is the index page loaded for any page...

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