"showwal $FILE 123bmc" show the content of the btree page in frame
123. "b" means decode the btree. "c" means show cell content.
"m" means give a map of the btree page.
FossilOrigin-Name: 93b159da5d2570946fdcd7da120bf7eb82b840f3
only individual checksum failures are shown. And only show failures, not
correct checksums.
FossilOrigin-Name: 4e2bf57549a8d50fc0993386c724eb4a2b35c9fe