Adding logic to unpivot to handle boolean columns. #208
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One quick comment, curious to hear what you think, but otherwise this is looking really good to me! Thanks for taking the time @avishalom :)
| @@ -52,7 +52,12 @@ Arguments: | |||
| {%- endfor %} | |||
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| cast('{{ col.column }}' as {{ dbt_utils.type_string() }}) as {{ field_name }}, | |||
| cast({{ col.column }} as {{ cast_to }}) as {{ value_name }} | |||
| cast( {% if col.data_type == 'boolean' %} | |||
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I think we might want to make a cross-database adapter macro that renders this case when statement. That will let us use this logic in other macros. Additionally, I think that databases like BigQuery will use the type BOOL, not boolean (though I'd need to double-check this to be sure!). The adapter macro pattern will let us define custom macro implementations on a per-adapter basis here
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Should I wrap this in a targtt=redshift test?
(I'm too lazy to connect to databases that I don't normally use to test. maybe other members have them ready.)
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Nope - I'd just add a file in this dir using a file like this one as a template. You can call this file something like bool_cast.sql. The default__ implementation can just return
cast({{ col }} as {{ type }})
and the Redshift implementation can use the case when ... statement you've shown here.
I actually did some more digging, and it looks like Redshift is the only database dbt supports which lacks the ability to cast a boolean to a string. Go figure.
Regardless, I'd rather encapsulate this logic in an adapter-macro than hardcode any if target == redshift logic in here. Code like that becomes a big mess real fast :)
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Thanks, I wasn't familiar with that pattern.
oh, it looks like safe_cast
already exists, though I'm not 100% sure what the behavior is,
can you override an sql function with a macro?
or do you need to invoke it as .<macro_name>() ?
within the namespace of the package dbt_utils line 19 is ambiguous with a macro named the same as a function.
the fact that it isn't an error probably means that with no package qualifier the native function takes precedence.
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Closing in favor of #305 |
A boolean value will be replaced with 'true' or 'false'.
The rest remains unchanged.
added test