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+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines. The results of this test also vary depending
+-- on the configured block size. This test has several different expected
+-- results files to handle the following possibilities:
+--
+-- BLCKSZ end file
+-- 8K LE checksum.out
+-- 8K BE checksum_1.out
+--
+-- In future we might provide additional expected-results files for other
+-- block sizes, but there seems little point as long as so many other
+-- test scripts also show false failures for non-default block sizes.
+--
+
+-- This is to label the results files with blocksize:
+SHOW block_size;
+
+SHOW block_size \gset
+
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+ page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+ page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+ page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+ page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+ page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+ page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+ FROM generate_series(0, 100, 50) AS a (blkno);