What is full table scan ?
Full table scans are usually the slowest method of scanning a table
When it occurs ?
Index is not used / not created
Depends on statistics gathered on referred object
When to avoid full table scans ?
For large tables
What should be indexed ?
Primary key,foreign keys,columns used to join tables ,columns used frequently in where clause ,columns with maximum number of distinct values
What is the hint for fts ?
Select /*+ full(tablespace name here) */ a.emp_code
from employees a
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