ORACLE Rank, Dense_rank, row_number
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SQL> desc user_order;
Name Null? Type
----------------------------------------- -------- ----------------------------
REGION_ID NUMBER(2)
CUSTOMER_ID NUMBER(2)
CUSTOMER_SALES NUMBER
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SQL> select * from user_order order by customer_sales;
REGION_ID CUSTOMER_ID CUSTOMER_SALES
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5 1 151162
10 29 903383
6 7 &nb
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Oracle Process Structure
Oracle takes advantage of various types of processes:
¡¡—User process: Started at the time a database user requests connection to the Oracle server
—Server process: Connects to the Oracle instance and is started when a user establishes a session
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