added collation processing in UNION merging

temporary table BLOB now is longblob


mysql-test/r/create.result:
  blob size changed for safety
mysql-test/r/type_blob.result:
  blob size changed for safety
mysql-test/r/type_ranges.result:
  blob size changed for safety
mysql-test/r/union.result:
  blob size changed for safety
  new tests of UNION types merging
mysql-test/t/union.test:
  new tests of UNION types merging
sql/field.h:
  blob size changed for safety
sql/item.cc:
  processing of collation added
  added comment
sql/item.h:
  joining of UNION fields may failed now, because of incompatibility of collations
sql/sql_union.cc:
  joining of UNION fields may failed now, because of incompatibility of collations

mysql-test/r/create.result

@@ -404,7 +404,7 @@ d	date			0000-00-00
 e	char(1)				
 f	datetime			0000-00-00 00:00:00	
 g	time			00:00:00	
-h	mediumblob				
+h	longblob				
 dd	time			00:00:00	
 select * from t2;
 a	b	c	d	e	f	g	h	dd

mysql-test/r/type_blob.result

@@ -508,5 +508,5 @@ drop table t1;
 create table t1 select load_file('../../std_data/words.dat');
 show full fields from t1;
 Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
-load_file('../../std_data/words.dat')	mediumblob	NULL	YES		NULL		select,insert,update,references	
+load_file('../../std_data/words.dat')	longblob	NULL	YES		NULL		select,insert,update,references	
 drop table t1;

mysql-test/r/type_ranges.result

@@ -271,8 +271,8 @@ Field	Type	Collation	Null	Key	Default	Extra	Privileges	Comment
 auto	bigint(17) unsigned	NULL		PRI	0		select,insert,update,references	
 t1	bigint(1)	NULL			0		select,insert,update,references	
 t2	char(1)	latin1_swedish_ci					select,insert,update,references	
-t3	mediumtext	latin1_swedish_ci					select,insert,update,references	
-t4	mediumtext	latin1_bin					select,insert,update,references	
+t3	longtext	latin1_swedish_ci					select,insert,update,references	
+t4	longtext	latin1_bin					select,insert,update,references	
 select * from t2;
 auto	t1	t2	t3	t4
 11	1	a	aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa	bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

mysql-test/r/union.result

@@ -556,8 +556,8 @@ t1	CREATE TABLE `t1` (
   `a` double(4,1) NOT NULL default '0.0'
 ) TYPE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
-create table t2 (it1 tinyint, it2 tinyint not null, i int not null, ib bigint, f float, d double, y year, da date, dt datetime, sc char(10), sv varchar(10), b blob);
-insert into t2 values (NULL, 1, 3, 4, 1.5, 2.5, 1972, '1972-10-22', '1972-10-22 11:50', 'testc', 'testv', 'tetetetetest');
+create table t2 (it1 tinyint, it2 tinyint not null, i int not null, ib bigint, f float, d double, y year, da date, dt datetime, sc char(10), sv varchar(10), b blob, tx text);
+insert into t2 values (NULL, 1, 3, 4, 1.5, 2.5, 1972, '1972-10-22', '1972-10-22 11:50', 'testc', 'testv', 'tetetetetest', 'teeeeeeeeeeeest');
 create table t1 SELECT it2 from t2 UNION select it1 from t2;
 select * from t1;
 it2
@@ -720,7 +720,7 @@ tetetetetest
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `dt` blob
+  `dt` longblob
 ) TYPE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 create table t1 SELECT sv from t2 UNION select b from t2;
@@ -731,7 +731,7 @@ tetetetetest
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `sv` blob
+  `sv` longblob
 ) TYPE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 create table t1 SELECT i from t2 UNION select d from t2 UNION select b from t2;
@@ -745,4 +745,61 @@ Table	Create Table
 t1	CREATE TABLE `t1` (
   `i` blob
 ) TYPE=MyISAM DEFAULT CHARSET=latin1
+drop table t1;
+create table t1 SELECT sv from t2 UNION select tx from t2;
+select * from t1;
+sv
+testv
+teeeeeeeeeeeest
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `sv` text
+) TYPE=MyISAM DEFAULT CHARSET=latin1
+drop table t1;
+create table t1 SELECT b from t2 UNION select tx from t2;
+select * from t1;
+b
+tetetetetest
+teeeeeeeeeeeest
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `b` longblob
+) TYPE=MyISAM DEFAULT CHARSET=latin1
 drop table t1,t2;
+create table t1 (d decimal(10,1));
+create table t2 (d decimal(10,9));
+insert into t1 values ("100000000.0");
+insert into t2 values ("1.23456780");
+create table t3 select * from t2 union select * from t1;
+select * from t3;
+d
+1.234567800
+100000000.0
+show create table t3;
+Table	Create Table
+t3	CREATE TABLE `t3` (
+  `d` decimal(10,9) default NULL
+) TYPE=MyISAM DEFAULT CHARSET=latin1
+drop table t1,t2,t3;
+create table t1 select 1 union select -1;
+select * from t1;
+1
+1
+-1
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `1` bigint(1) NOT NULL default '0'
+) TYPE=MyISAM DEFAULT CHARSET=latin1
+drop table t1;
+create table t1 select _latin1"test" union select _latin2"testt" ;
+ERROR HY000: Illegal mix of collations (latin1_swedish_ci,COERCIBLE) and (latin2_general_ci,COERCIBLE) for operation 'UNION'
+create table t1 select _latin2"test" union select _latin2"testt" ;
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `test` char(5) character set latin2 NOT NULL default ''
+) TYPE=MyISAM DEFAULT CHARSET=latin1
+drop table t1;

mysql-test/t/union.test

@@ -321,8 +321,8 @@ select * from t1;
 show create table t1;
 drop table t1;
 
-create table t2 (it1 tinyint, it2 tinyint not null, i int not null, ib bigint, f float, d double, y year, da date, dt datetime, sc char(10), sv varchar(10), b blob);
-insert into t2 values (NULL, 1, 3, 4, 1.5, 2.5, 1972, '1972-10-22', '1972-10-22 11:50', 'testc', 'testv', 'tetetetetest');
+create table t2 (it1 tinyint, it2 tinyint not null, i int not null, ib bigint, f float, d double, y year, da date, dt datetime, sc char(10), sv varchar(10), b blob, tx text);
+insert into t2 values (NULL, 1, 3, 4, 1.5, 2.5, 1972, '1972-10-22', '1972-10-22 11:50', 'testc', 'testv', 'tetetetetest', 'teeeeeeeeeeeest');
 
 create table t1 SELECT it2 from t2 UNION select it1 from t2;
 select * from t1;
@@ -391,4 +391,29 @@ drop table t1;
 create table t1 SELECT i from t2 UNION select d from t2 UNION select b from t2;
 select * from t1;
 show create table t1;
+drop table t1;
+create table t1 SELECT sv from t2 UNION select tx from t2;
+select * from t1;
+show create table t1;
+drop table t1;
+create table t1 SELECT b from t2 UNION select tx from t2;
+select * from t1;
+show create table t1;
 drop table t1,t2;
+create table t1 (d decimal(10,1));
+create table t2 (d decimal(10,9));
+insert into t1 values ("100000000.0");
+insert into t2 values ("1.23456780");
+create table t3 select * from t2 union select * from t1;
+select * from t3;
+show create table t3;
+drop table t1,t2,t3;
+create table t1 select 1 union select -1;
+select * from t1;
+show create table t1;
+drop table t1;
+-- error 1266
+create table t1 select _latin1"test" union select _latin2"testt" ;
+create table t1 select _latin2"test" union select _latin2"testt" ;
+show create table t1;
+drop table t1;
\ No newline at end of file

sql/field.h

@@ -941,7 +941,7 @@ class Field_blob :public Field_str {
 	     struct st_table *table_arg, CHARSET_INFO *cs)
     :Field_str((char*) 0,len_arg, maybe_null_arg ? (uchar*) "": 0,0,
 	       NONE, field_name_arg, table_arg, cs),
-    geom_flag(true), packlength(3)
+    geom_flag(true), packlength(4)
     {
       flags|= BLOB_FLAG;
     }

sql/item.cc

@@ -2005,17 +2005,24 @@ Item_type_holder::Item_type_holder(THD *thd, Item *item)
     field_example= ((Item_field*) item)->field;
   else
     field_example= 0;
+  collation.set(item->collation);
 }
 
 
-// STRING_RESULT, REAL_RESULT, INT_RESULT, ROW_RESULT
+/*
+  STRING_RESULT, REAL_RESULT, INT_RESULT, ROW_RESULT
+
+  ROW_RESULT should never appear in Item_type_holder::join_types,
+  but it is included in following table just to make table full
+  (there DBUG_ASSERT in function to catch ROW_RESULT)
+*/
 static Item_result type_convertor[4][4]=
 {{STRING_RESULT, STRING_RESULT, STRING_RESULT, ROW_RESULT},
  {STRING_RESULT, REAL_RESULT,   REAL_RESULT,   ROW_RESULT},
  {STRING_RESULT, REAL_RESULT,   INT_RESULT,    ROW_RESULT},
  {ROW_RESULT,    ROW_RESULT,    ROW_RESULT,    ROW_RESULT}};
 
-void Item_type_holder::join_types(THD *thd, Item *item)
+bool Item_type_holder::join_types(THD *thd, Item *item)
 {
   bool change_field= 0, skip_store_field= 0;
   Item_result new_type= type_convertor[item_type][item->result_type()];
@@ -2045,14 +2052,20 @@ void Item_type_holder::join_types(THD *thd, Item *item)
       (max_length < item->max_length) ||
       ((new_type == INT_RESULT) &&
        (decimals < item->decimals)) ||
-      (!maybe_null && item->maybe_null))
+      (!maybe_null && item->maybe_null) ||
+      (item_type == STRING_RESULT && new_type == STRING_RESULT &&
+       !my_charset_same(collation.collation, item->collation.collation)))
   {
     // new field has some parameters worse then current
     skip_store_field|= (change_field &&
 			(max_length > item->max_length) ||
 			((new_type == INT_RESULT) &&
 			 (decimals > item->decimals)) ||
-			(maybe_null && !item->maybe_null));
+			(maybe_null && !item->maybe_null) ||
+			(item_type == STRING_RESULT &&
+			 new_type == STRING_RESULT &&
+			 !my_charset_same(collation.collation,
+					  item->collation.collation)));
     /*
       It is safe assign pointer on field, because it will be used just after
       all JOIN::prepare calls and before any SELECT execution
@@ -2062,12 +2075,25 @@ void Item_type_holder::join_types(THD *thd, Item *item)
     else
       field_example= ((Item_field*) item)->field;
 
+    const char *old_cs= collation.collation->name,
+      *old_derivation= collation.derivation_name();
+    if (item_type == STRING_RESULT && collation.aggregate(item->collation))
+    {
+      my_error(ER_CANT_AGGREGATE_2COLLATIONS, MYF(0),
+	       old_cs, old_derivation,
+	       item->collation.collation->name,
+	       item->collation.derivation_name(),
+	       "UNION");
+      return 1;
+    }
+
     max_length= max(max_length, item->max_length);
     decimals= max(decimals, item->decimals);
     maybe_null|= item->maybe_null;
     item_type= new_type;
   }
   DBUG_ASSERT(item_type != ROW_RESULT);
+  return 0;
 }
 
 

sql/item.h

@@ -1005,7 +1005,7 @@ class Item_type_holder: public Item
   double val();
   longlong val_int();
   String *val_str(String*);
-  void join_types(THD *thd, Item *);
+  bool join_types(THD *thd, Item *);
   Field *example() { return field_example; }
 };
 

sql/sql_union.cc

@@ -197,7 +197,8 @@ int st_select_lex_unit::prepare(THD *thd, select_result *sel_result)
       Item *type, *item;
       while((type= tp++, item= it++))
       {
-	((Item_type_holder*)type)->join_types(thd, item);
+	if (((Item_type_holder*)type)->join_types(thd, item))
+	  DBUG_RETURN(-1)
       }
     }
   }