Adding support for querying Hive VIew in Athena

[sajjanbh]

Currently, Athena doesn't support querying of Hive View because it is incompatible with Presto View. These incompatibilities span across view attributes as well in the column schema. So, a View can either be queried from Hive or from Presto/Athena side. Therefore, it kind of defeats the purpose of having central metastore like Glue Catalog.

Nevertheless, since this Lambda function is used as Connector between Athena and Glue catalog, it can be used to modify the Hive View definition in flight and make it compatible for Presto. Then by the time, Athena needs to query it, it'll be able to do so as a regular Presto View.

Also, updated the code to handle issue #5 .

Issue #, if available: 5

Description of changes:

• Added a logic to identify whether a view is Presto View or not.
• If it isn't a Presto View, it considers it as Hive View. Then, calls a function to convert Hive view to Presto view.
• Inside this function, it adds necessary attributes to make it appear as Presto View. Also, since there are some significant differences in how column schema are defined between Hive and Presto views, it attempts to modify them accordingly.
• In my tests, this allows for successful querying of Hive Views in Athena. For some unique/edge cases, it may need to be addressed accordingly.

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[SSHShah256]

hoping to get this feature to allow querying of views via athena cross account lambda.