On Thu, Oct 15, 2020, at 2:52 AM, Kotofos online wrote:
>
> Hi,
> Could you shed some light on what I might be doing incorrectly? I have this
> text() SELECT * query on top of a one-column sub-query and in the result, I
> am not getting that column name.
>
> ```
> stmt = text('select "FirstName", from "Customer"')
> stmt = select('*').select_from(stmt.columns().alias())
> print(stmt)
>
> SELECT *
> FROM (select "FirstName", from "Customer") AS anon_1
> ```
>
> This is works, but produces incorrect column name in the output:
> ```
> res = engine.execute(stmt)
> keys = res.fetchall()[0].keys()
> print(keys)
When using select(), the names in the result rows come from those which were
provided to the select() method. they are matched to those of the actual
cursor if possible but not if they don't match.
>
> ['*']
> ```
>
> But when the subquery has two columns, then it works as expected:
> ```
> stmt = text('select "FirstName", "LastName" from "Customer"')
> stmt = select('*').select_from(stmt.columns().alias())
> res = engine.execute(stmt)
> keys = res.fetchall()[0].keys()
> print(keys)
>
> ['FirstName', 'LastName']
> ```
> So, is there a better way to wrap text query? Why column name is lost in the
> first case? Is it a bug?
it's basically undefined behavior you're dealing with. you wouldn't want to
pass a "*" to select(). I'm sure there's more context to what you actually
need to do, but in the example above, there's no need to use a subquery, just
invoke the text() construct directly.
>
> Tested on 1.3.20 and 1.2.19
>
> --
> SQLAlchemy -
> The Python SQL Toolkit and Object Relational Mapper
>
> http://www.sqlalchemy.org/
>
> To post example code, please provide an MCVE: Minimal, Complete, and
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SQLAlchemy -
The Python SQL Toolkit and Object Relational Mapper
http://www.sqlalchemy.org/
To post example code, please provide an MCVE: Minimal, Complete, and Verifiable
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