We have a table of 3113GB, and we are planning to vacuum it in non business hours i.e. 12AM to 4AM, So my queries are:
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3. Will the operation be completed in the given time frame? how to check the same.
Given the size of the table, it will probably take several days.
No matter how long it takes, this is an excellent argument for partitioning Very Large Tables: many maintenance tasks are made much easier.
I can only agree with this comment. The main issue I see is the available disk space, as the partitioning process will include copying the whole table.