From: Date: November 6 2006 11:13pm Subject: bk commit into 4.1 tree (cmiller:1.2542) BUG#23411 List-Archive: http://lists.mysql.com/commits/14911 X-Bug: 23411 Message-Id: <20061106221321.EA2F183049@zippy> Below is the list of changes that have just been committed into a local 4.1 repository of cmiller. When cmiller does a push these changes will be propagated to the main repository and, within 24 hours after the push, to the public repository. For information on how to access the public repository see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html ChangeSet@stripped, 2006-11-06 17:13:19-05:00, cmiller@stripped +4 -0 Bug#23411: ... MOD-ing zero returns strange result The Item_func_mod objects never had maybe_null set, so users had no reason to expect that they can be NULL, and may therefore deduce wrong results. Now, set maybe_null. BitKeeper/etc/collapsed@stripped, 2006-11-06 16:41:39-05:00, cmiller@stripped +1 -0 BitKeeper/etc/collapsed@stripped, 2006-11-06 15:40:16-05:00, cmiller@stripped +1 -0 mysql-test/r/func_test.result@stripped, 2006-11-06 17:13:17-05:00, cmiller@stripped +75 -0 Verify that the predictions are true. mysql-test/t/func_test.test@stripped, 2006-11-06 17:13:17-05:00, cmiller@stripped +32 -0 Verify that the predictions are true. sql/item_func.cc@stripped, 2006-11-06 17:13:17-05:00, cmiller@stripped +2 -1 MOD functions may be NULL. # This is a BitKeeper patch. What follows are the unified diffs for the # set of deltas contained in the patch. The rest of the patch, the part # that BitKeeper cares about, is below these diffs. # User: cmiller # Host: zippy.cornsilk.net # Root: /home/cmiller/work/mysql/bug23411/my41-bug23411 --- 1.267/sql/item_func.cc 2006-11-06 17:13:21 -05:00 +++ 1.268/sql/item_func.cc 2006-11-06 17:13:21 -05:00 @@ -96,7 +96,7 @@ Item_func::Item_func(THD *thd, Item_func /* - Resolve references to table column for a function and it's argument + Resolve references to table column for a function and its argument SYNOPSIS: fix_fields() @@ -707,6 +707,7 @@ longlong Item_func_mod::val_int() void Item_func_mod::fix_length_and_dec() { Item_num_op::fix_length_and_dec(); + maybe_null= 1; } --- 1.1/BitKeeper/etc/collapsed 2006-11-06 17:13:21 -05:00 +++ 1.3/BitKeeper/etc/collapsed 2006-11-06 17:13:21 -05:00 @@ -1 +1,3 @@ 452a92d0-31-8wSzSfZi165fcGcXPA +454a7ef8gdvE_ddMlJyghvOAkKPNOQ +454f8960jsVT_kMKJtZ9OCgXoba0xQ --- 1.28/mysql-test/r/func_test.result 2006-11-06 17:13:21 -05:00 +++ 1.29/mysql-test/r/func_test.result 2006-11-06 17:13:21 -05:00 @@ -183,3 +183,78 @@ select 5.1 mod 3, 5.1 mod -3, -5.1 mod 3 select 5 mod 3, 5 mod -3, -5 mod 3, -5 mod -3; 5 mod 3 5 mod -3 -5 mod 3 -5 mod -3 2 2 -2 -2 +select (12%0) <=> null as '1'; +1 +1 +select (12%0) is null as '1'; +1 +1 +select 12%0 as 'NULL'; +NULL +NULL +select 12%2 as '0'; +0 +0 +select 12%NULL as 'NULL'; +NULL +NULL +select 12 % null as 'NULL'; +NULL +NULL +select null % 12 as 'NULL'; +NULL +NULL +select null % 0 as 'NULL'; +NULL +NULL +select 0 % null as 'NULL'; +NULL +NULL +select null % null as 'NULL'; +NULL +NULL +select (12 mod 0) <=> null as '1'; +1 +1 +select (12 mod 0) is null as '1'; +1 +1 +select 12 mod 0 as 'NULL'; +NULL +NULL +select 12 mod 2 as '0'; +0 +0 +select 12 mod null as 'NULL'; +NULL +NULL +select null mod 12 as 'NULL'; +NULL +NULL +select null mod 0 as 'NULL'; +NULL +NULL +select 0 mod null as 'NULL'; +NULL +NULL +select null mod null as 'NULL'; +NULL +NULL +select mod(12.0, 0) as 'NULL'; +NULL +NULL +select mod(12, 0.0) as 'NULL'; +NULL +NULL +select mod(12, NULL) as 'NULL'; +NULL +NULL +select mod(12.0, NULL) as 'NULL'; +NULL +NULL +select mod(NULL, 2) as 'NULL'; +NULL +NULL +select mod(NULL, 2.0) as 'NULL'; +NULL +NULL --- 1.26/mysql-test/t/func_test.test 2006-11-06 17:13:21 -05:00 +++ 1.27/mysql-test/t/func_test.test 2006-11-06 17:13:21 -05:00 @@ -108,4 +108,36 @@ select 5.1 mod 3, 5.1 mod -3, -5.1 mod 3 select 5 mod 3, 5 mod -3, -5 mod 3, -5 mod -3; +# +# Bug#23411: The "%" (MOD) operator is not documented; MOD-ing zero returns strange result +# Manual: "Division by zero produces a NULL result" +# +select (12%0) <=> null as '1'; +select (12%0) is null as '1'; +select 12%0 as 'NULL'; +select 12%2 as '0'; +select 12%NULL as 'NULL'; +select 12 % null as 'NULL'; +select null % 12 as 'NULL'; +select null % 0 as 'NULL'; +select 0 % null as 'NULL'; +select null % null as 'NULL'; + +select (12 mod 0) <=> null as '1'; +select (12 mod 0) is null as '1'; +select 12 mod 0 as 'NULL'; +select 12 mod 2 as '0'; +select 12 mod null as 'NULL'; +select null mod 12 as 'NULL'; +select null mod 0 as 'NULL'; +select 0 mod null as 'NULL'; +select null mod null as 'NULL'; + +select mod(12.0, 0) as 'NULL'; +select mod(12, 0.0) as 'NULL'; +select mod(12, NULL) as 'NULL'; +select mod(12.0, NULL) as 'NULL'; +select mod(NULL, 2) as 'NULL'; +select mod(NULL, 2.0) as 'NULL'; + # End of 4.1 tests