Tip#1. Solving Access Permission Conundrum
After creating a new database in Hive, you only need Hive ranger policy to allow reading the tables in the new database from Hive/Beeline/Beeline-Ranger.
But when reading the Hive table from Spark, it also needs a HDFS permission policy, in addition to the Hive ranger policy as above.
Tip#2. Running Queries on Hive Tables
For internal/managed ACID tables, use
hive.executeQuery("SELECT * FROM DB.TABLE")
For external non-ACID tables, use this below instead of over
hive.executeQuery() to get 10x performance increase
spark.sql("SELECT * FROM DB.TABLE")
Tip#3. Check if a Table is Managed or External
Now if you are wondering if a table is managed or external, you can run this below in Hive/Beeline/Beeline-ranger which tells you if a table is external or managed table
DESCRIBE FORMATTED db.table_name;
It should show the information regarding the table. Check the Table Type value it should either say Table Type: