The Road to 2.18 - Customfields

[Joel Peshkin]

Christopher Hicks wrote:

>On Fri, 12 Mar 2004, David Miller wrote:
>
>  
>
>>But the performance on queries is going to suck badly once you try to
>>get querying working on custom fields, because of all the extra table
>>joins you need in order to match the fields.
>>    
>>
>
>The only reason those extra table joins would be happening is if you were 
>querying on a custom field and in that case there would only be one extra 
>join per field queried.  That seems a pretty small price to pay.  
>Presumably most of the time people are going to be querying on the 
>non-custom fields anyway which won't be any worse than it is now.
>
>  
>
Er... 

One left join per field either selected or used as a criteria.  

I'd like to understand the actual performance impact of this.  In many 
ways, Sean's approach is cleaner than addind a bunch of columns to the 
tables, but we need some numbers on the performance impact before we can 
decide.

-Joel