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Reasons to use a cartesian join

Yazan: dp | 01 February 2011 | No Comments
Categories: Computers, Software

All over the Internet you’ll find people telling you that cartesian joins are a bad idea. And for the 99% of the time you’d run in to them, they are. But I found a legitimate use for them. I needed to get a count of records from table A for all the records in table [...]

Nested JOINs in MySQL

Yazan: dp | 27 January 2011 | No Comments
Categories: Computers, Software

Image via Wikipedia Sometimes, I have a need to SELECT data from a table, LEFT JOINed with another table (because the data in the second table is optional), but then INNER JOINed with a third table. Unfortunately, the resulting query runs (essentially) as two INNER JOINs, removing data that I want. That’s where nested joins [...]

How to fix strange characters in MySQL database – Vinh Pham

Yazan: dp | 26 January 2010 | 4 Comments
Categories: Servers

I admit, I borrowed this from How to fix strange characters in MySQL database – Vinh Pham. But I also added a few more that were missing; update <table> set <field> = replace(<field>, ‘’’, ‘\”); update <table> set <field> = replace(<field>, ‘…’, ‘&hellip;’); update <table> set <field> = replace(<field>, ‘–’, ‘-’); update <table> set <field> [...]