Oracle Database Interview Question

1. Different between Delete,Truncate & Drop.
   Delete: Delete is a DML operation and we can delete partial data by using where clause. Deleted data can be recovered by using rollback.No impact on dependent object.This command is slower, because it use undo segment and triggers will get fired (on delete trigger). Deleted data is temporary store in then redo log.
   Truncate: Truncate is DDL (Autocommit) operation.All rows will be removed and cannot use where clause.Data lost forever and no impact dependent object.Truncate command is faster and no trigger will get invoked.
   Drop: DDL Command and removes the dependent object. Data can be recovered if Flashback option is on. Dependent object will have to be created.
   
   
2. What is SQL?

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