When a table has an index on an expression, then inserting a zeroblob into
an indexed column of that table might cause the zeroblob to be truncated.

<blockquote><verbatim>
CREATE TABLE t1(a,b,c);
CREATE INDEX t1bbc ON t1(b, b+c);
INSERT INTO t1(a,b,c) VALUES(1,zeroblob(8),3);
SELECT a, b, length(b), c FROM t1;
</verbatim></blockquote>

The correct answer is

<blockquote><verbatim>
1,X'0000000000000000',8,3
</verbatim></blockquote>

But the answer returned is:

<blockquote><verbatim>
1,X'',0,3
</verbatim></blockquote>

This issue was discovered during internal testing.  There have been no
reports of this from the wild.