02-15-2018 04:23 AM
I am trying to automatise the testing of the data in Impala. Is there a way to check, if two columns from the different tables have the same data type? Currently we are doing this check manually, by
describe formatted a; describe formatted b;
but I would like to see result in the way:
select case when a.type = b.type then "TRUE" else "FALSE" end from (describe formatted x.column1 as type) a, (describe formatted y.column1 as type) b;
Can you please advise, if there is a way to implement second example?
02-15-2018 08:22 AM
Just a thought...
For your use case, instead of try that in impala, you login to your metadata database (ex: mysql, postgresql, etc) where all your table name, column name, datatypes are stored
>mysql –u root –p
Get the Metadata for your table and compare the datatype easily
02-15-2018 11:09 AM
There's no easy way to do this right now unfortunately. I agree it would be great if we exposed table metadata as system tables so you could use SQL to query metadata.