This strategy requires changing the format of the encryption page to store the identifier (number) of the encryption key.

Comparison

copynofastercomplexcomplex

	copy	in place
The amount of disk input-output	> 2x	2x+ ^{(depends on WAL settings)}
The amount of required disk space	2x	limited by WAL settings	2x
Data overhead	no	yes^{(1-2 bytes per page)}
Performance^{(rough estimate)}	faster	slower
Implementation complexity ^{(rough estimate)}
Stable topology, read-only	simple	simple
Online updates	complex	simple
Unstable topology	complex	simple

Copy with re-encryption design.

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