report migration from SQL server to Oracle
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I have a report in SQL servver and I am migrating this to Oracle. The approach I used in SQL server is load sum(sales) , person for given month into temporary tables (hash tables) and use this table to join with other transaction tables show the details, but when it comes to oracle I am not sure if I can use the same method here, because hash tables (temporary tables in SQL server) are specific to session and might not create any problem with output, please advise if there is anything in oracle which is analogous to that. I came to know there are global temp tables in oracle, do they work in the manner I mentinoed above, also if a user has no create/drop table privileges can they still use gloabal temp tables? please help us me. 