Hi Matthieu

Adding on to Michael's comments.

Hive is good for batch processing and generating reports over larger dats sets. It is not meant for point to point queries, if you have much of those then hive is not the choice.

You can get your daily data processed in hadoop and load them on to hive tables. Hive has a new feature 'INSERT INTO' for adding data into exiting tables/partitions. For your case you can create a partitioned table based on date and load each day's processed data into corresponding date partitions. With partitions you will have an advantage - if you issue a query on some date/dates only those partitions will be scanned rather than the whole table.

Tableau, MicroStragegy, Pentaho etc supports reporting on top of hive tables.
If you are looking at some static predefined reports, you can do the aggregation in hive, take the final aggregated results to any rdbms using Sqoop and connect any reporting tool of your choice to that.

Some urls for reference

Bejoy KS