[Rt-devel] Re: [rt-users] Where does QueryBuilder refer tables?

[Ruslan Zakirov]

On 7/27/05, Ahalya_Nathan at mudnebr.com <Ahalya_Nathan at mudnebr.com> wrote:
>  
> Hi Ruslan, 
> Your mail did clarify some doubt in my head about RT but i still have one
> more problem i.e., I have a query for selecting tickets with  id<2000 and
> Requestor.EmailAddress="Ahalya_Nathan at mudnebr.com" .I know that the code
> from the Tickets_Overlay_SQL.pm is being referred. What i am unable to
> figure out is how does the Users table get referred since the
> Requestor.EmailAddress is present in the Users table?  Also the Limit
> function in the DBIx::SearchBuilder accepts arguments such as TABLE =>
> $self->{'table'}, which i know is the Tickets table.How or where is the
> Users table being referred. I can see that the functions for Joining tables
> have been done in the _LinkFieldLimit function in the Tickets_Overlay.pm
> program. But this function is not being referred at all for selecting
> tickets. 
Yeah, Tickets*.pm is most hard thing to understand, because it's very
extended subclass of the DBIx::SB.

There is  %FIELDS hash in Tickets_Overlay.pm which contain special
metadata for searches.
There is also %dispatch hash in the same file, that contains links to
functions associated with field type.
So if you have query - q{ id < 2000 and Requestor.EmailAddress =
'x at y.com' } then RT do next:
* RT splits it by AGGREGATORS: 'and', 'or' ...
* split parts to $field, $op, $value
* find $field metadata in %FIELDS hash
* fetch field type(ENUM, LINK, ...) from metadata
* fetch method link(dispatcher) from %dispatch hash
* run dispatcher method

if $field has '.'(like in 'Requestor.EmailAddress') then it's
translated like 'field_name.field_extension' and RT parse
field_extension in dispatcher method.

Huh, something like this.

>  
> It will be real helpful if you could give me some pointers on this. 
May be you want write some "simple" script and you don't all this
internals, so you can show us small code and place where you don't
understand what to do.

>  
> Regards,
>  Ahalya Nathan
>  Senior Programmer / Analyst
>  Information Technology, Metropolitan Utilities District 
>  (402) 449-8218 phone
>  (402) 449-8131 fax
>  ahalya_nathan at mudnebr.com 
>  
>  
>  
>  Ruslan Zakirov <ruslan.zakirov at gmail.com> 
> 
> 07/27/2005 11:09 AM 
>  
> Please respond to
>  Ruslan Zakirov <ruslan.zakirov at gmail.com> 
>  
>  
> To "Ahalya_Nathan at mudnebr.com" <Ahalya_Nathan at mudnebr.com> 
>  
> cc rt-users at lists.bestpractical.com 
>  
> Subject Re: [rt-users] Where does QueryBuilder refer tables? 
>  
>  
>  
>  
>  
> On 7/27/05, Ahalya_Nathan at mudnebr.com <Ahalya_Nathan at mudnebr.com> wrote:
>  >  
>  > Hi Ruslan, 
>  > The documentation that you gave was very helpful but i am kindoff trying
> to
>  > understand this piece of code in the Tickets_Overlay_SQL.pm program., 
>  >  
>  >   $self->SUPER::Limit( FIELD           => 'EffectiveId', 
>  >                      ENTRYAGGREGATOR => 'AND', 
>  >                      OPERATOR        => '=', 
>  >                      QUOTEVALUE      => 0, 
>  >                      VALUE           => 'main.id' 
>  >  
>  > Could you tell me how this works? What does "main" imply to be? Is the
> Limit
>  > function used for retrieving information from the database. 
>  Base class where Limit lives is DBIx::SearchBuilder, see its docs.
>  Limit method limits colection of records with some condition.
>  In code you quote RT adds condition to Tickets select and select would
>  be looking something like:
>  SELECT main.* FROM Tickets main, ... WHERE main.EffectiveId = main.id ...
>  
>  This is required step when you want select Ticket(s) by some condition
>  and also tickets that was merged.
>  
>  
>  >  
>  > Regards,
>  >  Ahalya Nathan
>  >  Senior Programmer / Analyst
>  >  Information Technology, Metropolitan Utilities District 
>  >  (402) 449-8218 phone
>  >  (402) 449-8131 fax
>  >  ahalya_nathan at mudnebr.com 
>  >  
>  >  
>  >  
>  >  Ruslan Zakirov <ruslan.zakirov at gmail.com> 
>  > 
>  > 07/26/2005 06:11 PM 
>  >  
>  > Please respond to
>  >  Ruslan Zakirov <ruslan.zakirov at gmail.com> 
>  >  
>  >  
>  > To "Ahalya_Nathan at mudnebr.com" <Ahalya_Nathan at mudnebr.com> 
>  >  
>  > cc rt-users at lists.bestpractical.com,
>  > rt-users-bounces at lists.bestpractical.com 
>  >  
>  > Subject Re: [rt-users] Where does QueryBuilder refer tables? 
>  >  
>  >  
>  >  
>  >  
>  >  
>  > On 7/27/05, Ahalya_Nathan at mudnebr.com <Ahalya_Nathan at mudnebr.com> wrote:
>  >  >  
>  >  > Hi all, 
>  >  >  
>  >  > Could anyone tell me how or which program refers tickets or other
> tables
>  > to
>  >  > display the resultset for Query Builder?. I have been trying to figure
>  > out
>  >  > how it refers the tables to display the resultset but no luck so far. 
>  >  >  
>  >  > It will be very helpful if anyone could give me a suggestion. 
>  >  http://wiki.bestpractical.com/index.cgi?ObjectModel
>  >  http://wiki.bestpractical.com/index.cgi?GlobalObjects
>  >  lib/RT/Tickets*.pm
>  >  
>  >  This is only I can say.
>  >  > 
>  >  >  
>  >  >  Regards,
>  >  >  Ahalya Nathan
>  >  >  Senior Programmer / Analyst
>  >  >  Information Technology, Metropolitan Utilities District 
>  >  >  (402) 449-8218 phone
>  >  >  (402) 449-8131 fax
>  >  >  ahalya_nathan at mudnebr.com 
>  >  > _______________________________________________
>  >  >
>  >
> http://lists.bestpractical.com/cgi-bin/mailman/listinfo/rt-users
>  >  > 
>  >  > Be sure to check out the RT Wiki at http://wiki.bestpractical.com
>  >  > 
>  >  > 
>  >  
>  >  
>  >  -- 
>  >  Best regards, Ruslan.
>  >  
>  >  
>  
>  
>  -- 
>  Best regards, Ruslan.
>  
>  


-- 
Best regards, Ruslan.