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Hi All, 
My client recently suggested to use compression on all CHAR and VARCHAR fields like the below:

Hi Experts ,
What are the disadvantages of compression . Especially is there any scenario when compressed column create an issue while joining with another table and uncompressed column .
Thanks in advance for your reply  .

Hi All,
I would like to know If there would be any impact of I/O if we perform any join operations or filter operations on the compressed column considering compression property is majorly a space saving technique.
Hope I made myself clear.