[Sqlalchemy-tickets] Issue #3018: Bad parameter conversion on execute when it is list with one element (zzzeek/sqlalchemy)

[maxdamage <iss...@bi...>]

New issue 3018: Bad parameter conversion on execute when it is list with one element
https://bitbucket.org/zzzeek/sqlalchemy/issue/3018/bad-parameter-conversion-on-execute-when

maxdamage:



```
#!python
some_list = [1, ] # list with one element

query = "SELECT * FROM some_table WHERE id IN :param_list "

params = { "param_list": some_list }

result = db_session.execute(expression.text(query), params)

```

query will look like:

```
#!sql

SELECT * FROM some_table WHERE id IN ('1',)
```


When we want to pass list as a parameter to query, and the list has one element there is added coma at the end  that breaks the query. 
When list has more elements there is no additional coma at the end so the query is fine.

Tested on 0.7.4. Didn't check newer versions.