Fixed problem with t1 LEFT_JOIN t2 ... WHERE t2.date_column IS NULL when date_column is declared as NOT NULL.

Author: monty@hundin.mysql.fi

.bzrignore

@@ -303,3 +303,5 @@ support-files/mysql.server
 support-files/mysql.spec
 tags
 tmp/*
+bdb/include/db_ext.h
+bdb/include/mutex_ext.h

BUILD/SETUP.sh

@@ -48,7 +48,7 @@ fast_cflags="-O3 -fno-omit-frame-pointer"
 # this is one is for someone who thinks 1% speedup is worth not being
 # able to backtrace
 reckless_cflags="-O3 -fomit-frame-pointer "
-debug_cflags="-DEXTRA_DEBUG -DFORCE_INIT_OF_VARS -DSAFEMALLOC -DSAFE_MUTEX -O0"
+debug_cflags="-DEXTRA_DEBUG -DFORCE_INIT_OF_VARS -DSAFEMALLOC -DSAFE_MUTEX -O1"
 
 base_cxxflags="-felide-constructors -fno-exceptions -fno-rtti"
 

Docs/manual.texi

@@ -46844,6 +46844,9 @@ not yet 100% confident in this code.
 @appendixsubsec Changes in release 3.23.45
 @itemize @bullet
 @item
+Fixed problem with @code{t1 LEFT_JOIN t2 ... WHERE t2.date_column IS NULL} when
+date_column was declared as @code{NOT NULL}.
+@item
 Fixed bug with BDB tables and keys on @code{BLOB}'s.
 @item
 Fixed bug in @code{MERGE} tables on OS with 32 bit file pointers.

mysql-test/r/join.result

@@ -22,3 +22,8 @@ a
 2
 a	a	b
 2	2	3
+d	d
+2001-08-01	NULL
+0000-00-00	NULL
+d
+0000-00-00

mysql-test/t/join.test

@@ -106,9 +106,17 @@ INSERT INTO t1 VALUES (1,1),(1,2),(1,3),(1,4),(1,5),(1,6),(1,7),(2,3);
 CREATE TABLE t2 (
   a int(11) default NULL
 ) TYPE=MyISAM;
- 
 INSERT INTO t2 VALUES (2),(3);
- 
 SELECT t1.a,t2.a,b FROM t1,t2 WHERE t1.a=t2.a AND (t1.a=1 OR t1.a=2) AND b>=1 AND b<=3;
- 
 DROP TABLE t1, t2;
+
+#
+# TEST LEFT JOIN with DATE columns
+#
+
+CREATE TABLE t1 (d DATE NOT NULL);
+CREATE TABLE t2 (d DATE NOT NULL);
+INSERT INTO t1 (d) VALUES ('2001-08-01'),('0000-00-00');
+SELECT * FROM t1 LEFT JOIN t2 USING (d) WHERE t2.d IS NULL;
+SELECT * from t1 WHERE t1.d IS NULL;
+DROP TABLE t1,t2;

sql/sql_select.cc

@@ -3101,7 +3101,8 @@ remove_eq_conds(COND *cond,Item::cond_result *cond_value)
       /* fix to replace 'NULL' dates with '0' (shreeve@uci.edu) */
       else if (((field->type() == FIELD_TYPE_DATE) ||
 		(field->type() == FIELD_TYPE_DATETIME)) &&
-		(field->flags & NOT_NULL_FLAG))
+		(field->flags & NOT_NULL_FLAG) &&
+	       !field->table->maybe_null)
       {
 	COND *new_cond;
 	if ((new_cond= new Item_func_eq(args[0],new Item_int("0", 0, 2))))