[Evergreen-reports] Question about nullability

[Boyer, Jason A]

The Source Specifier box in the lower right shows what joins it will choose depending on the "Nullable" column for the link you followed. If you use Default, it doesn't list anything (so you don't know the join without consulting the debug page, they're not all the same.); if the Parent is nullable it is a right outer join; if the is child is nullable it's a left outer; and if None are nullable that's inner. The bad news is that it appears that a right outer join is all you get with circ_mods from copies, which still leaves the null circ mod items out.

I just throw the raw value of circ_modifier from the fields displayed when Item is selected on the left instead of following the Circulation Modifier link. That displays or filters on the code and if that's all you're doing with the circ mod it's one less thing to worry about.

Jason

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Jason Boyer
Indiana State Library
http://library.in.gov/
317-234-2128

-----Original Message-----
From: evergreen-reports-bounces at list.evergreen-ils.org [mailto:evergreen-reports-bounces at list.evergreen-ils.org] On Behalf Of Beth Willis
Sent: Monday, April 14, 2014 11:51 AM
To: evergreen-reports >> Evergreen Community Reports Email List
Subject: [Evergreen-reports] Question about nullability

I am working on a report template that uses asset.copy as the initial source.  From there, I want to create joins to asset.call_number, config.circ_modifier, and config.copy_status sources.

I need to create an outer join to the config.circ_modifier source because some of our copy records have null values for circ_modifier. 
But, I cannot seem to generate SQL with this outer join.

As I understand it, if I select the "default" option I should get an inner join, but if I select the "none" option I should get an outer join.  This is not the case.

Has anyone else run into this?  If so, can you tell me what I am doing incorrectly?  I have attached the SQL to this e-mail.

Thanks in advance for any assistance.
Beth


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Beth Willis
Digital & Catalog Librarian
NOBLE, Inc.
26 Cherry Hill Drive
Danvers, MA 01923