From 20d704978ddb14dee414f40f28bd58f82b21711c Mon Sep 17 00:00:00 2001 From: Gleb Shchepa Date: Sun, 31 Oct 2010 19:04:38 +0300 Subject: [PATCH] Bug #52160: crash and inconsistent results when grouping by a function and column The bugreport reveals two different bugs about grouping on a function: 1) grouping by the TIME_TO_SEC function result caused a server crash or wrong results and 2) grouping by the function returning a blob caused an unexpected "Duplicate entry" error and wrong result. Details for the 1st bug: TIME_TO_SEC() returns NULL if its argument is invalid (empty string for example). Thus its nullability depends not only on the nullability of its arguments but also on their values. Fixed by (overoptimistically) setting TIME_TO_SEC() to be nullable despite the nullability of its arguments. Details for the 2nd bug: The server is unable to create indices on blobs without explicit blob key part length. However, this fact was ignored for blob function result fields of GROUP BY intermediate tables. Fixed by disabling GROUP BY index creation for blob function result fields like regular blob fields. mysql-test/r/func_time.result: Test case for bug #52160. mysql-test/r/type_blob.result: Test case for bug #52160. mysql-test/t/func_time.test: Test case for bug #52160. mysql-test/t/type_blob.test: Test case for bug #52160. sql/item_timefunc.h: Bug #52160: crash and inconsistent results when grouping by a function and column TIME_TO_SEC() returns NULL if its argument is invalid (empty string for example). Thus its nullability depends not only Fixed by (overoptimistically) setting TIME_TO_SEC() to be nullable despite the nullability of its arguments. sql/sql_select.cc: Bug #52160: crash and inconsistent results when grouping by a function and column The server is unable to create indices on blobs without explicit blob key part length. However, this fact was ignored for blob function result fields of GROUP BY intermediate tables. Fixed by disabling GROUP BY index creation for blob function result fields like regular blob fields. --- mysql-test/r/func_time.result | 14 ++++++++++++++ mysql-test/r/type_blob.result | 11 +++++++++++ mysql-test/t/func_time.test | 10 ++++++++++ mysql-test/t/type_blob.test | 16 ++++++++++++++++ sql/item_timefunc.h | 1 + sql/sql_select.cc | 2 ++ 6 files changed, 54 insertions(+) diff --git a/mysql-test/r/func_time.result b/mysql-test/r/func_time.result index 4ff4cfa586b..48e837f180f 100644 --- a/mysql-test/r/func_time.result +++ b/mysql-test/r/func_time.result @@ -1343,4 +1343,18 @@ SELECT 1 FROM t1 ORDER BY @x:=makedate(a,a); 1 1 DROP TABLE t1; +# +# Bug #52160: crash and inconsistent results when grouping +# by a function and column +# +CREATE TABLE t1(a CHAR(10) NOT NULL); +INSERT INTO t1 VALUES (''),(''); +SELECT COUNT(*) FROM t1 GROUP BY TIME_TO_SEC(a); +COUNT(*) +2 +Warnings: +Warning 1292 Truncated incorrect time value: '' +Warning 1292 Truncated incorrect time value: '' +Warning 1292 Truncated incorrect time value: '' +DROP TABLE t1; End of 5.1 tests diff --git a/mysql-test/r/type_blob.result b/mysql-test/r/type_blob.result index 08c30d884fd..e6fd49b4247 100644 --- a/mysql-test/r/type_blob.result +++ b/mysql-test/r/type_blob.result @@ -974,3 +974,14 @@ ERROR 42000: Display width out of range for column 'cast as char' (max = 4294967 explain select convert(1, binary(999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999)); ERROR 42000: Display width out of range for column 'cast as char' (max = 4294967295) End of 5.0 tests +# Bug #52160: crash and inconsistent results when grouping +# by a function and column +CREATE FUNCTION f1() RETURNS TINYBLOB RETURN 1; +CREATE TABLE t1(a CHAR(1)); +INSERT INTO t1 VALUES ('0'), ('0'); +SELECT COUNT(*) FROM t1 GROUP BY f1(), a; +COUNT(*) +2 +DROP FUNCTION f1; +DROP TABLE t1; +End of 5.1 tests diff --git a/mysql-test/t/func_time.test b/mysql-test/t/func_time.test index e764906c374..8fce7072319 100644 --- a/mysql-test/t/func_time.test +++ b/mysql-test/t/func_time.test @@ -849,4 +849,14 @@ INSERT INTO t1 VALUES (0),(9.216e-096); SELECT 1 FROM t1 ORDER BY @x:=makedate(a,a); DROP TABLE t1; +--echo # +--echo # Bug #52160: crash and inconsistent results when grouping +--echo # by a function and column +--echo # + +CREATE TABLE t1(a CHAR(10) NOT NULL); +INSERT INTO t1 VALUES (''),(''); +SELECT COUNT(*) FROM t1 GROUP BY TIME_TO_SEC(a); +DROP TABLE t1; + --echo End of 5.1 tests diff --git a/mysql-test/t/type_blob.test b/mysql-test/t/type_blob.test index 460da1c1614..4e097edf73d 100644 --- a/mysql-test/t/type_blob.test +++ b/mysql-test/t/type_blob.test @@ -612,3 +612,19 @@ explain select convert(1, binary(4294967296)); explain select convert(1, binary(999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999)); --echo End of 5.0 tests + +--echo # Bug #52160: crash and inconsistent results when grouping +--echo # by a function and column + +CREATE FUNCTION f1() RETURNS TINYBLOB RETURN 1; + +CREATE TABLE t1(a CHAR(1)); +INSERT INTO t1 VALUES ('0'), ('0'); + +SELECT COUNT(*) FROM t1 GROUP BY f1(), a; + +DROP FUNCTION f1; +DROP TABLE t1; + +--echo End of 5.1 tests + diff --git a/sql/item_timefunc.h b/sql/item_timefunc.h index ef86406e1be..47bb9509582 100644 --- a/sql/item_timefunc.h +++ b/sql/item_timefunc.h @@ -331,6 +331,7 @@ public: const char *func_name() const { return "time_to_sec"; } void fix_length_and_dec() { + maybe_null= TRUE; decimals=0; max_length=10*MY_CHARSET_BIN_MB_MAXLEN; } diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 08bd0c28738..77d4447fd0f 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -15198,6 +15198,8 @@ calc_group_buffer(JOIN *join,ORDER *group) { key_length+= 8; } + else if (type == MYSQL_TYPE_BLOB) + key_length+= MAX_BLOB_WIDTH; // Can't be used as a key else { /*