Cacti Graphs for Apache Not Working? Check Your IPv6

I was wondering earlier why my Apache Cacti graphs were all graphing 0s. Looking to test manually, I see it’s either 0s or -1s like below.

Looking at the Apache access log on the target server, I noticed Cacti was trying to connect to the IPv6 loopback address “::1”.

Fortunately this was easy …

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Optimizing OR’ed WHERE Clauses Between JOIN’ed Tables

OR conditions are normally difficult to optimize when used on different columns, a pain when the columns are of range conditions and worst when done between 2 or more different tables. Look at my example below, the original query  is trying to find rows which conditions are based on columns from the JOIN’ed tables.

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