jasonkhadka edited a comment on issue #9194:
URL: https://github.com/apache/arrow/issues/9194#issuecomment-760857808
> Like a keyword to indicate that missing columns in this list can be
ignored instead of raising an error?
Yes an `error='ignore'` keyword would be a perfect solution.
> The name of the missing field is in the error message?
Name of the missing field is there in the error message. But if you want to
get the field name out of error so that you can use that to drop it from the
list of columns and try again to read the parquet, it is difficult.
The error only contains the message, and it would be great if the error also
included the field name as property, so error handling could be built.
Example :
```
from pyarrow.lib import ArrowInvalid
read_columns = ['a','b','X']
df = pd.DataFrame({'a': [1, 2, 3], 'b': ['foo', 'bar', 'jar']})
file_name = '/tmp/my_df.pq'
df.to_parquet(file_name)
try:
df = pd.read_parquet(file_name, columns = read_columns)
except ArrowInvalid as e:
inval = e
```
```
inval.args
>("Field named 'X' not found or not unique in the schema.",)
```
You could parse the message above to get 'X', but that is a bit of hectic
solution. Would be great if the error message contained the field name. So, you
could do for example :
```
inval.field
> 'X'
```
And with this, one could remove 'X' form the list 'read_columns' and then
retry reading the parquet.
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