Change of internal key_field=NULL handling to avoid error messages.

Optimized SELECT DISTINCT ... ORDER BY ... LIMIT
Fixed reference to uninitalized variable

mysql-test/r/distinct.result

@@ -198,6 +198,30 @@ a
 select distinct 1 from t1,t3 where t1.a=t3.a;
 1
 1
+explain SELECT distinct t1.a from t1;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	index	NULL	PRIMARY	4	NULL	2	Using index
+explain SELECT distinct t1.a from t1 order by a desc;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	index	NULL	PRIMARY	4	NULL	2	Using index
+explain SELECT t1.a from t1 group by a order by a desc;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	index	NULL	PRIMARY	4	NULL	2	Using index
+explain SELECT distinct t1.a from t1 order by a desc limit 1;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t1	index	NULL	PRIMARY	4	NULL	2	Using index
+explain SELECT distinct a from t3 order by a desc limit 2;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t3	index	NULL	a	5	NULL	204	Using index
+explain SELECT distinct a,b from t3 order by a+1;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t3	ALL	NULL	NULL	NULL	NULL	204	Using temporary; Using filesort
+explain SELECT distinct a,b from t3 order by a limit 10;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t3	index	NULL	a	5	NULL	204	Using temporary
+explain SELECT a,b from t3 group by a,b order by a+1;
+table	type	possible_keys	key	key_len	ref	rows	Extra
+t3	ALL	NULL	NULL	NULL	NULL	204	Using temporary; Using filesort
 drop table t1,t2,t3,t4;
 CREATE TABLE t1 (name varchar(255));
 INSERT INTO t1 VALUES ('aa'),('ab'),('ac'),('ad'),('ae');

mysql-test/r/func_math.result

@@ -31,9 +31,10 @@ log10(100)	log10(18)	log10(-4)	log10(0)	log10(NULL)
 select pow(10,log10(10)),power(2,4);
 pow(10,log10(10))	power(2,4)
 10.000000	16.000000
+set @@rand_seed1=10000000,@@rand_seed2=1000000;
 select rand(999999),rand();
 rand(999999)	rand()
-0.014231365187309	0.8078568166195
+0.014231365187309	0.028870999839968
 select pi(),sin(pi()/2),cos(pi()/2),abs(tan(pi())),cot(1),asin(1),acos(0),atan(1);
 PI()	sin(pi()/2)	cos(pi()/2)	abs(tan(pi()))	cot(1)	asin(1)	acos(0)	atan(1)
 3.141593	1.000000	0.000000	0.000000	0.64209262	1.570796	1.570796	0.785398

mysql-test/r/innodb.result

@@ -1036,3 +1036,25 @@ n	d
 1	30
 2	20
 drop table t1,t2;
+create table t1 (a int, b int) type=innodb;
+insert into t1 values(20,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a;
+b	ifnull(t2.b,"this is null")
+NULL	this is null
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+b	ifnull(t2.b,"this is null")
+NULL	this is null
+insert into t1 values(10,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+b	ifnull(t2.b,"this is null")
+NULL	this is null
+NULL	this is null
+drop table t1;
+create table t1 (a varchar(10) not null) type=myisam;
+create table t2 (b varchar(10) not null unique) type=innodb;
+select t1.a from t1,t2 where t1.a=t2.b;
+a
+drop table t1,t2;

mysql-test/r/null.result

@@ -6,7 +6,7 @@ select 1 | NULL,1 & NULL,1+NULL,1-NULL;
 NULL	NULL	NULL	NULL
 select NULL=NULL,NULL<>NULL,IFNULL(NULL,1.1)+0,IFNULL(NULL,1) | 0;
 NULL=NULL	NULL<>NULL	IFNULL(NULL,1.1)+0	IFNULL(NULL,1) | 0
-NULL	NULL	1.1	1
+NULL	NULL	1	1
 select strcmp("a",NULL),(1<NULL)+0.0,NULL regexp "a",null like "a%","a%" like null;
 strcmp("a",NULL)	(1<NULL)+0.0	NULL regexp "a"	null like "a%"	"a%" like null
 NULL	NULL	NULL	NULL	NULL
@@ -56,3 +56,20 @@ indexed_field
 NULL
 NULL
 DROP TABLE t1;
+create table t1 (a int, b int) type=myisam;
+insert into t1 values(20,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a;
+b	ifnull(t2.b,"this is null")
+NULL	this is null
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+b	ifnull(t2.b,"this is null")
+NULL	this is null
+insert into t1 values(10,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+b	ifnull(t2.b,"this is null")
+NULL	this is null
+NULL	this is null
+drop table t1;

mysql-test/t/distinct.test

@@ -88,6 +88,16 @@ select distinct t1.a from t1,t3 where t1.a=t3.a;
 #flush status;
 select distinct 1 from t1,t3 where t1.a=t3.a;
 #show status like 'Handler%';
+
+explain SELECT distinct t1.a from t1;
+explain SELECT distinct t1.a from t1 order by a desc;
+explain SELECT t1.a from t1 group by a order by a desc;
+explain SELECT distinct t1.a from t1 order by a desc limit 1;
+explain SELECT distinct a from t3 order by a desc limit 2;
+explain SELECT distinct a,b from t3 order by a+1;
+explain SELECT distinct a,b from t3 order by a limit 10;
+explain SELECT a,b from t3 group by a,b order by a+1;
+
 drop table t1,t2,t3,t4;
 
 CREATE TABLE t1 (name varchar(255));

mysql-test/t/func_math.test

@@ -13,6 +13,7 @@ select ln(exp(10)),exp(ln(sqrt(10))*2),ln(-1),ln(0),ln(NULL);
 select log2(8),log2(15),log2(-2),log2(0),log2(NULL);
 select log10(100),log10(18),log10(-4),log10(0),log10(NULL);
 select pow(10,log10(10)),power(2,4);
+set @@rand_seed1=10000000,@@rand_seed2=1000000;
 select rand(999999),rand();
 select pi(),sin(pi()/2),cos(pi()/2),abs(tan(pi())),cot(1),asin(1),acos(0),atan(1);
 select degrees(pi()),radians(360);

mysql-test/t/innodb.test

@@ -673,3 +673,26 @@ UPDATE t1,t2 SET t1.d=t2.d,t2.d=30 WHERE t1.n=t2.n;
 select * from t1;
 select * from t2;
 drop table t1,t2;
+
+#
+# Testing of IFNULL
+#
+create table t1 (a int, b int) type=innodb;
+insert into t1 values(20,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a;
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+insert into t1 values(10,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+drop table t1;
+
+#
+# Test of read_through not existing const_table
+#
+
+create table t1 (a varchar(10) not null) type=myisam;
+create table t2 (b varchar(10) not null unique) type=innodb;
+select t1.a from t1,t2 where t1.a=t2.b;
+drop table t1,t2;

mysql-test/t/null.test

@@ -34,3 +34,17 @@ SELECT * FROM t1 WHERE indexed_field=NULL;
 SELECT * FROM t1 WHERE indexed_field IS NULL;
 SELECT * FROM t1 WHERE indexed_field<=>NULL;
 DROP TABLE t1;
+
+#
+# Testing of IFNULL
+#
+create table t1 (a int, b int) type=myisam;
+insert into t1 values(20,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a;
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+insert into t1 values(10,null);
+select t2.b, ifnull(t2.b,"this is null") from t1 as t2 left join t1 as t3 on
+t2.b=t3.a order by 1;
+drop table t1;

sql/field.h

@@ -1058,7 +1058,7 @@ Field *make_field(char *ptr, uint32 field_length,
 uint pack_length_to_packflag(uint type);
 uint32 calc_pack_length(enum_field_types type,uint32 length);
 bool set_field_to_null(Field *field);
-bool set_field_to_null_with_conversions(Field *field);
+bool set_field_to_null_with_conversions(Field *field, bool no_conversions);
 uint find_enum(TYPELIB *typelib,const char *x, uint length);
 ulonglong find_set(TYPELIB *typelib,const char *x, uint length);
 bool test_if_int(const char *str,int length);

sql/field_conv.cc

@@ -122,8 +122,26 @@ set_field_to_null(Field *field)
 }
 
 
+/*
+  Set field to NULL or TIMESTAMP or to next auto_increment number
+
+  SYNOPSIS
+    set_field_to_null_with_conversions()
+    field		Field to update
+    no_conversion	Set to 1 if we should return 1 if field can't
+			take null values.
+			If set to 0 we will do store the 'default value'
+			if the field is a special field. If not we will
+			give an error.
+
+  RETURN VALUES
+    0		Field could take 0 or an automatic conversion was used
+    1		Field could not take NULL and no conversion was used.
+		If no_conversion was not set, an error message is printed
+*/
+
 bool
-set_field_to_null_with_conversions(Field *field)
+set_field_to_null_with_conversions(Field *field, bool no_conversions)
 {
   if (field->real_maybe_null())
   {
@@ -131,6 +149,8 @@ set_field_to_null_with_conversions(Field *field)
     field->reset();
     return 0;
   }
+  if (no_conversions)
+    return 1;
 
   /*
     Check if this is a special type, which will get a special walue
@@ -156,8 +176,6 @@ set_field_to_null_with_conversions(Field *field)
 }
 
 
-
-
 static void do_skip(Copy_field *copy __attribute__((unused)))
 {
 }

sql/item.cc

@@ -419,7 +419,7 @@ void Item_field::save_org_in_field(Field *to)
   if (field->is_null())
   {
     null_value=1;
-    set_field_to_null_with_conversions(to);
+    set_field_to_null_with_conversions(to, 1);
   }
   else
   {
@@ -429,12 +429,12 @@ void Item_field::save_org_in_field(Field *to)
   }
 }
 
-bool Item_field::save_in_field(Field *to)
+bool Item_field::save_in_field(Field *to, bool no_conversions)
 {
   if (result_field->is_null())
   {
     null_value=1;
-    return set_field_to_null_with_conversions(to);
+    return set_field_to_null_with_conversions(to, no_conversions);
   }
   else
   {
@@ -461,9 +461,9 @@ bool Item_field::save_in_field(Field *to)
     1	 Field doesn't support NULL values and can't handle 'field = NULL'
 */   
 
-bool Item_null::save_in_field(Field *field)
+bool Item_null::save_in_field(Field *field, bool no_conversions)
 {
-  return set_field_to_null_with_conversions(field);
+  return set_field_to_null_with_conversions(field, no_conversions);
 }
 
 
@@ -485,7 +485,7 @@ bool Item_null::save_safe_in_field(Field *field)
 }
 
 
-bool Item::save_in_field(Field *field)
+bool Item::save_in_field(Field *field, bool no_conversions)
 {
   if (result_type() == STRING_RESULT ||
       result_type() == REAL_RESULT &&
@@ -496,7 +496,7 @@ bool Item::save_in_field(Field *field)
     str_value.set_quick(buff,sizeof(buff));
     result=val_str(&str_value);
     if (null_value)
-      return set_field_to_null_with_conversions(field);
+      return set_field_to_null_with_conversions(field, no_conversions);
     field->set_notnull();
     field->store(result->ptr(),result->length());
     str_value.set_quick(0, 0);
@@ -513,7 +513,7 @@ bool Item::save_in_field(Field *field)
   {
     longlong nr=val_int();
     if (null_value)
-      return set_field_to_null_with_conversions(field);
+      return set_field_to_null_with_conversions(field, no_conversions);
     field->set_notnull();
     field->store(nr);
   }
@@ -521,7 +521,7 @@ bool Item::save_in_field(Field *field)
 }
 
 
-bool Item_string::save_in_field(Field *field)
+bool Item_string::save_in_field(Field *field, bool no_conversions)
 {
   String *result;
   result=val_str(&str_value);
@@ -532,7 +532,7 @@ bool Item_string::save_in_field(Field *field)
   return 0;
 }
 
-bool Item_int::save_in_field(Field *field)
+bool Item_int::save_in_field(Field *field, bool no_conversions)
 {
   longlong nr=val_int();
   if (null_value)
@@ -542,7 +542,7 @@ bool Item_int::save_in_field(Field *field)
   return 0;
 }
 
-bool Item_real::save_in_field(Field *field)
+bool Item_real::save_in_field(Field *field, bool no_conversions)
 {
   double nr=val();
   if (null_value)
@@ -597,7 +597,7 @@ longlong Item_varbinary::val_int()
 }
 
 
-bool Item_varbinary::save_in_field(Field *field)
+bool Item_varbinary::save_in_field(Field *field, bool no_conversions)
 {
   field->set_notnull();
   if (field->result_type() == STRING_RESULT)
@@ -658,9 +658,10 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables)
   return 0;
 }
 
+
 /*
-** If item is a const function, calculate it and return a const item
-** The original item is freed if not returned
+  If item is a const function, calculate it and return a const item
+  The original item is freed if not returned
 */
 
 Item_result item_cmp_type(Item_result a,Item_result b)

sql/item.h

@@ -53,11 +53,11 @@ public:
   void set_name(char* str,uint length=0);
   void init_make_field(Send_field *tmp_field,enum enum_field_types type);
   virtual bool fix_fields(THD *,struct st_table_list *);
-  virtual bool save_in_field(Field *field);
+  virtual bool save_in_field(Field *field, bool no_conversions);
   virtual void save_org_in_field(Field *field)
-    { (void) save_in_field(field); }
+  { (void) save_in_field(field, 1); }
   virtual bool save_safe_in_field(Field *field)
-    { return save_in_field(field); }
+  { return save_in_field(field, 1); }
   virtual bool send(THD *thd, String *str);
   virtual bool eq(const Item *, bool binary_cmp) const;
   virtual Item_result result_type () const { return REAL_RESULT; }
@@ -130,7 +130,7 @@ public:
   }
   void make_field(Send_field *field);
   bool fix_fields(THD *,struct st_table_list *);
-  bool save_in_field(Field *field);
+  bool save_in_field(Field *field,bool no_conversions);
   void save_org_in_field(Field *field);
   table_map used_tables() const;
   enum Item_result result_type () const
@@ -156,7 +156,7 @@ public:
   longlong val_int();
   String *val_str(String *str);
   void make_field(Send_field *field);
-  bool save_in_field(Field *field);
+  bool save_in_field(Field *field, bool no_conversions);
   bool save_safe_in_field(Field *field);
   enum Item_result result_type () const
   { return STRING_RESULT; }
@@ -190,7 +190,7 @@ public:
   double val() { return (double) value; }
   String *val_str(String*);
   void make_field(Send_field *field);
-  bool save_in_field(Field *field);
+  bool save_in_field(Field *field, bool no_conversions);
   bool basic_const_item() const { return 1; }
   Item *new_item() { return new Item_int(name,value,max_length); }
   void print(String *str);
@@ -232,7 +232,7 @@ public:
     max_length=length;
   }
   Item_real(double value_par) :value(value_par) {}
-  bool save_in_field(Field *field);
+  bool save_in_field(Field *field, bool no_conversions);
   enum Type type() const { return REAL_ITEM; }
   double val() { return value; }
   longlong val_int() { return (longlong) (value+(value > 0 ? 0.5 : -0.5));}
@@ -277,7 +277,7 @@ public:
   double val() { return atof(str_value.ptr()); }
   longlong val_int() { return strtoll(str_value.ptr(),(char**) 0,10); }
   String *val_str(String*) { return (String*) &str_value; }
-  bool save_in_field(Field *field);
+  bool save_in_field(Field *field, bool no_conversions);
   void make_field(Send_field *field);
   enum Item_result result_type () const { return STRING_RESULT; }
   bool basic_const_item() const { return 1; }
@@ -298,7 +298,7 @@ public:
   Item_default() { name= (char*) "DEFAULT"; }
   enum Type type() const { return DEFAULT_ITEM; }
   void make_field(Send_field *field) {}
-  bool save_in_field(Field *field)
+  bool save_in_field(Field *field, bool no_conversions)
   {
     field->set_default();
     return 0;
@@ -339,7 +339,7 @@ public:
   double val() { return (double) Item_varbinary::val_int(); }
   longlong val_int();
   String *val_str(String*) { return &str_value; }
-  bool save_in_field(Field *field);
+  bool save_in_field(Field *field, bool no_conversions);
   void make_field(Send_field *field);
   enum Item_result result_type () const { return INT_RESULT; }
   unsigned int size_of() { return sizeof(*this);}  
@@ -401,7 +401,8 @@ public:
   bool send(THD *thd, String *tmp)	{ return (*ref)->send(thd, tmp); }
   void make_field(Send_field *field)	{ (*ref)->make_field(field); }
   bool fix_fields(THD *,struct st_table_list *);
-  bool save_in_field(Field *field)	{ return (*ref)->save_in_field(field); }
+  bool save_in_field(Field *field, bool no_conversions)
+  { return (*ref)->save_in_field(field, no_conversions); }
   void save_org_in_field(Field *field)	{ (*ref)->save_org_in_field(field); }
   enum Item_result result_type () const { return (*ref)->result_type(); }
   table_map used_tables() const		{ return (*ref)->used_tables(); }
@@ -421,9 +422,9 @@ class Item_int_with_ref :public Item_int
 public:
   Item_int_with_ref(longlong i, Item *ref_arg) :Item_int(i), ref(ref_arg)
   {}
-  bool save_in_field(Field *field)
+  bool save_in_field(Field *field, bool no_conversions)
   {
-    return ref->save_in_field(field);
+    return ref->save_in_field(field, no_conversions);
   }
   unsigned int size_of() { return sizeof(*this);}  
 };

sql/item_cmpfunc.cc

@@ -48,7 +48,7 @@ static bool convert_constant_item(Field *field, Item **item)
 {
   if ((*item)->const_item() && (*item)->type() != Item::INT_ITEM)
   {
-    if (!(*item)->save_in_field(field) &&
+    if (!(*item)->save_in_field(field, 1) &&
 	!((*item)->null_value))
     {
       Item *tmp=new Item_int_with_ref(field->val_int(), *item);
@@ -444,15 +444,29 @@ longlong Item_func_between::val_int()
   return 0;
 }
 
+static Item_result item_store_type(Item_result a,Item_result b)
+{
+  if (a == STRING_RESULT || b == STRING_RESULT)
+    return STRING_RESULT;
+  else if (a == REAL_RESULT || b == REAL_RESULT)
+    return REAL_RESULT;
+  else
+    return INT_RESULT;
+}
+
 void
 Item_func_ifnull::fix_length_and_dec()
 {
   maybe_null=args[1]->maybe_null;
   max_length=max(args[0]->max_length,args[1]->max_length);
   decimals=max(args[0]->decimals,args[1]->decimals);
-  cached_result_type=args[0]->result_type();
+  if ((cached_result_type=item_store_type(args[0]->result_type(),
+					  args[1]->result_type())) !=
+      REAL_RESULT)
+    decimals= 0;
 }
 
+
 double
 Item_func_ifnull::val()
 {

sql/item_func.cc

@@ -696,21 +696,20 @@ double Item_func_round::val()
 }
 
 
-double Item_func_rand::val()
+void Item_func_rand::fix_length_and_dec()
 {
-  THD* thd = current_thd;
+  decimals=NOT_FIXED_DEC; 
+  max_length=float_length(decimals);
   if (arg_count)
   {					// Only use argument once in query
     uint32 tmp= (uint32) (args[0]->val_int());
-    randominit(&thd->rand,(uint32) (tmp*0x10001L+55555555L),
+    if ((rand= (struct rand_struct*) sql_alloc(sizeof(*rand))))
+      randominit(rand,(uint32) (tmp*0x10001L+55555555L),
 		 (uint32) (tmp*0x10000001L));
-#ifdef DELETE_ITEMS
-    delete args[0];
-#endif
-    arg_count=0;
   }
-  else if (!thd->rand_used)
+  else
   {
+    THD *thd= current_thd;
     /*
       No need to send a Rand log event if seed was given eg: RAND(seed),
       as it will be replicated in the query as such.
@@ -722,8 +721,14 @@ double Item_func_rand::val()
     thd->rand_used=1;
     thd->rand_saved_seed1=thd->rand.seed1;
     thd->rand_saved_seed2=thd->rand.seed2;
+    rand= &thd->rand;
   }
-  return rnd(&thd->rand);
+}
+
+
+double Item_func_rand::val()
+{
+  return rnd(rand);
 }
 
 longlong Item_func_sign::val_int()

sql/item_func.h

@@ -459,20 +459,20 @@ public:
   const char *func_name() const { return truncate ? "truncate" : "round"; }
   double val();
   void fix_length_and_dec();
-  unsigned int size_of() { return sizeof(*this);}  
 };
 
 
 class Item_func_rand :public Item_real_func
 {
+  struct rand_struct *rand;
 public:
   Item_func_rand(Item *a) :Item_real_func(a) {}
   Item_func_rand()	  :Item_real_func()  {}
   double val();
   const char *func_name() const { return "rand"; }
-  void fix_length_and_dec() { decimals=NOT_FIXED_DEC; max_length=float_length(decimals); }
   bool const_item() const { return 0; }
   table_map used_tables() const { return RAND_TABLE_BIT; }
+  void fix_length_and_dec();
 };
 
 

sql/item_timefunc.cc

@@ -403,7 +403,7 @@ String *Item_date::val_str(String *str)
 }
 
 
-bool Item_date::save_in_field(Field *field)
+bool Item_date::save_in_field(Field *field, bool no_conversions)
 {
   TIME ltime;
   timestamp_type t_type=TIMESTAMP_FULL;
@@ -518,7 +518,7 @@ bool Item_func_now::get_date(TIME *res,
 }
 
 
-bool Item_func_now::save_in_field(Field *to)
+bool Item_func_now::save_in_field(Field *to, bool no_conversions)
 {
   to->set_notnull();
   to->store_time(&ltime,TIMESTAMP_FULL);

sql/item_timefunc.h

@@ -231,7 +231,7 @@ public:
   double val() { return (double) val_int(); }
   const char *func_name() const { return "date"; }
   void fix_length_and_dec() { decimals=0; max_length=10; }
-  bool save_in_field(Field *to);
+  bool save_in_field(Field *to, bool no_conversions);
   void make_field(Send_field *tmp_field)
   {
     init_make_field(tmp_field,FIELD_TYPE_DATE);
@@ -316,7 +316,7 @@ public:
   enum Item_result result_type () const { return STRING_RESULT; }
   double val()	     { return (double) value; }
   longlong val_int() { return value; }
-  bool save_in_field(Field *to);
+  bool save_in_field(Field *to, bool no_conversions);
   String *val_str(String *str)
   { str_value.set(buff,buff_length); return &str_value; }
   const char *func_name() const { return "now"; }

sql/opt_range.cc

@@ -1029,7 +1029,7 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part,
       field->cmp_type() != value->result_type())
     DBUG_RETURN(0);
 
-  if (value->save_in_field(field))
+  if (value->save_in_field(field, 1))
   {
     /* This happens when we try to insert a NULL field in a not null column */
     // TODO; Check if we can we remove the following block.
@@ -1038,9 +1038,9 @@ get_mm_leaf(PARAM *param, Field *field, KEY_PART *key_part,
       /* convert column_name <=> NULL -> column_name IS NULL */
       // Get local copy of key
       char *str= (char*) alloc_root(param->mem_root,1);
-      if (!*str)
+      if (!str)
 	DBUG_RETURN(0);
-      *str = 1;
+      *str= 1;
       DBUG_RETURN(new SEL_ARG(field,str,str));
     }
     DBUG_RETURN(&null_element);			// cmp with NULL is never true

sql/sql_base.cc

@@ -2098,7 +2098,7 @@ fill_record(List<Item> &fields,List<Item> &values)
   while ((field=(Item_field*) f++))
   {
     value=v++;
-    if (value->save_in_field(field->field))
+    if (value->save_in_field(field->field, 0))
       DBUG_RETURN(1);
   }
   DBUG_RETURN(0);
@@ -2116,7 +2116,7 @@ fill_record(Field **ptr,List<Item> &values)
   while ((field = *ptr++))
   {
     value=v++;
-    if (value->save_in_field(field))
+    if (value->save_in_field(field, 0))
       DBUG_RETURN(1);
   }
   DBUG_RETURN(0);

sql/sql_class.cc

@@ -158,9 +158,8 @@ THD::THD():user_time(0),fatal_error(0),last_insert_id_used(0),
   {
     pthread_mutex_lock(&LOCK_thread_count);
     ulong tmp=(ulong) (rnd(&sql_rand) * 3000000);
-    randominit(&rand, tmp + (ulong) start_time,
-	       tmp + (ulong) thread_id);
     pthread_mutex_unlock(&LOCK_thread_count);
+    randominit(&rand, tmp + (ulong) start_time, tmp + (ulong) thread_id);
   }
 }
 
@@ -171,16 +170,16 @@ THD::THD():user_time(0),fatal_error(0),last_insert_id_used(0),
 
 void THD::init(void)
 {
+  pthread_mutex_lock(&LOCK_global_system_variables);
+  variables= global_system_variables;
+  pthread_mutex_unlock(&LOCK_global_system_variables);
   server_status= SERVER_STATUS_AUTOCOMMIT;
-  update_lock_default= (variables.low_priority_updates ?
-			TL_WRITE_LOW_PRIORITY :
-			TL_WRITE);
   options= thd_startup_options;
   sql_mode=(uint) opt_sql_mode;
   open_options=ha_open_options;
-  pthread_mutex_lock(&LOCK_global_system_variables);
-  variables= global_system_variables;
-  pthread_mutex_unlock(&LOCK_global_system_variables);
+  update_lock_default= (variables.low_priority_updates ?
+			TL_WRITE_LOW_PRIORITY :
+			TL_WRITE);
   session_tx_isolation= (enum_tx_isolation) variables.tx_isolation;
 }
 

sql/sql_handler.cc

@@ -180,10 +180,10 @@ int mysql_ha_read(THD *thd, TABLE_LIST *tables,
       Item *item;
       for (key_len=0 ; (item=it_ke++) ; key_part++)
       {
-	item->save_in_field(key_part->field);
+	item->save_in_field(key_part->field, 1);
 	key_len+=key_part->store_length;
       }
-      if (!(key= (byte*) sql_calloc(ALIGN_SIZE(key_len))))
+      if (!(key= (byte*) thd->calloc(ALIGN_SIZE(key_len))))
       {
 	send_error(&thd->net,ER_OUTOFMEMORY);
 	goto err;

sql/sql_select.h

@@ -269,8 +269,7 @@ public:
   {}
   bool copy()
   {
-    item->save_in_field(to_field);
-    return err != 0;
+    return item->save_in_field(to_field, 1) || err != 0;
   }
   const char *name() const { return "func"; }
 };
@@ -293,7 +292,8 @@ public:
     if (!inited)
     {
       inited=1;
-      item->save_in_field(to_field);
+      if (item->save_in_field(to_field, 1))
+	err= 1;
     }
     return err != 0;
   }

sql/unireg.cc

@@ -574,7 +574,7 @@ static bool make_empty_rec(File file,enum db_type table_type,
     if (field->def &&
 	(regfield->real_type() != FIELD_TYPE_YEAR ||
 	 field->def->val_int() != 0))
-      field->def->save_in_field(regfield);
+      field->def->save_in_field(regfield, 1);
     else if (regfield->real_type() == FIELD_TYPE_ENUM &&
 	     (field->flags & NOT_NULL_FLAG))
     {