postreview fixes (BUG#5618 & BUG#5590)

sql/field.cc:
  fixed compatibility fields type detection
sql/item.cc:
  fixed compatibility fields detection with using standard method for all fields, also some bugs are fixed
sql/sql_derived.cc:
  some cleanup

3 files changed, 54 insertions, 46 deletions

diff --git a/sql/field.cc b/sql/field.cc
index 8a1c5ec5271..dbdd44633f0 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -172,42 +172,51 @@ static bool test_if_real(const char *str,int length, CHARSET_INFO *cs)
  FIELD_CAST_STOP
 */
 static Field::field_cast_enum field_cast_decimal[]=
-{Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
+{Field::FIELD_CAST_DECIMAL,
+ Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_tiny[]=
-{Field::FIELD_CAST_SHORT, Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG,
+{Field::FIELD_CAST_TINY,
+ Field::FIELD_CAST_SHORT, Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG,
  Field::FIELD_CAST_LONGLONG,
  Field::FIELD_CAST_FLOAT, Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_short[]=
-{Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG, Field::FIELD_CAST_LONGLONG,
+{Field::FIELD_CAST_SHORT,
+ Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG, Field::FIELD_CAST_LONGLONG,
  Field::FIELD_CAST_FLOAT, Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_medium[]=
-{Field::FIELD_CAST_LONG, Field::FIELD_CAST_LONGLONG,
+{Field::FIELD_CAST_MEDIUM,
+ Field::FIELD_CAST_LONG, Field::FIELD_CAST_LONGLONG,
  Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_long[]=
-{Field::FIELD_CAST_LONGLONG,
+{Field::FIELD_CAST_LONG,
+ Field::FIELD_CAST_LONGLONG,
  Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_longlong[]=
-{Field::FIELD_CAST_DOUBLE,
+{Field::FIELD_CAST_LONGLONG,
+ Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_float[]=
-{Field::FIELD_CAST_DOUBLE,
+{Field::FIELD_CAST_FLOAT,
+ Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_double[]=
-{Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
+{Field::FIELD_CAST_DOUBLE,
+ Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_null[]=
-{Field::FIELD_CAST_DECIMAL, Field::FIELD_CAST_TINY, Field::FIELD_CAST_SHORT,
+{Field::FIELD_CAST_NULL,
+ Field::FIELD_CAST_DECIMAL, Field::FIELD_CAST_TINY, Field::FIELD_CAST_SHORT,
  Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG, Field::FIELD_CAST_LONGLONG,
  Field::FIELD_CAST_FLOAT, Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_TIMESTAMP, Field::FIELD_CAST_YEAR,
@@ -218,44 +227,54 @@ static Field::field_cast_enum field_cast_null[]=
  Field::FIELD_CAST_GEOM, Field::FIELD_CAST_ENUM, Field::FIELD_CAST_SET,
  Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_timestamp[]=
-{Field::FIELD_CAST_DATETIME,
+{Field::FIELD_CAST_TIMESTAMP,
+ Field::FIELD_CAST_DATETIME,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_year[]=
-{Field::FIELD_CAST_SHORT, Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG,
+{Field::FIELD_CAST_YEAR,
+ Field::FIELD_CAST_SHORT, Field::FIELD_CAST_MEDIUM, Field::FIELD_CAST_LONG,
  Field::FIELD_CAST_LONGLONG,
  Field::FIELD_CAST_FLOAT, Field::FIELD_CAST_DOUBLE,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_date[]=
-{Field::FIELD_CAST_DATETIME,
+{Field::FIELD_CAST_DATE,
+ Field::FIELD_CAST_DATETIME,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_newdate[]=
-{Field::FIELD_CAST_DATETIME,
+{Field::FIELD_CAST_NEWDATE,
+ Field::FIELD_CAST_DATETIME,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_time[]=
-{Field::FIELD_CAST_DATETIME,
+{Field::FIELD_CAST_TIME,
+ Field::FIELD_CAST_DATETIME,
  Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_datetime[]=
-{Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
+{Field::FIELD_CAST_DATETIME,
+ Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
  Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_string[]=
-{Field::FIELD_CAST_VARSTRING, Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
+{Field::FIELD_CAST_STRING,
+ Field::FIELD_CAST_VARSTRING, Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_varstring[]=
-{Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
+{Field::FIELD_CAST_VARSTRING,
+ Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_blob[]=
-{Field::FIELD_CAST_STOP};
+{Field::FIELD_CAST_BLOB,
+ Field::FIELD_CAST_STOP};
+/*
+  Geometrical, enum and set fields can be casted only to expressions
+*/
 static Field::field_cast_enum field_cast_geom[]=
 {Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_enum[]=
-{Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
- Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
+{Field::FIELD_CAST_STOP};
 static Field::field_cast_enum field_cast_set[]=
-{Field::FIELD_CAST_STRING, Field::FIELD_CAST_VARSTRING,
- Field::FIELD_CAST_BLOB, Field::FIELD_CAST_STOP};
+{Field::FIELD_CAST_STOP};
 // Array of pointers on conversion table for all fields types casting
 static Field::field_cast_enum *field_cast_array[]=
 {0, //FIELD_CAST_STOP
diff --git a/sql/item.cc b/sql/item.cc
index 457360e63d3..ea095df3aaa 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -2517,38 +2517,29 @@ bool Item_type_holder::join_types(THD *thd, Item *item)
   if (field_example && item->type() == Item::FIELD_ITEM)
   {
     Field *field= ((Item_field *)item)->field;
-    Field::field_cast_enum field_type= field->field_cast_type();
-
-    if (field_type != Field::FIELD_CAST_ENUM &&
-        field_type != Field::FIELD_CAST_SET)
+    /* Can old example field store new data? */
+    if ((change_field=
+          !field->field_cast_compatible(field_example->field_cast_type())))
     {
-      if (field_example->field_cast_type() != field_type)
-      {
-        if (!(change_field=
-              field_example->field_cast_compatible(field->field_cast_type())))
-        {
-          /*
-            if old field can't store value of 'worse' new field we will make
-            decision about result field type based only on Item result type
-          */
-          if (!field->field_cast_compatible(field_example->field_cast_type()))
-            skip_store_field= 1;
-        }
-      }
+      /*
+        if old field can't store value of 'worse' new field we will make
+        decision about result field type based only on Item result type
+      */
+      if (!field_example->field_cast_compatible(field->field_cast_type()))
+        skip_store_field= 1;
     }
-    else
-      skip_store_field= 1;
   }
   else if (field_example || item->type() == Item::FIELD_ITEM)
+  {
+    /* expression can't be mixed with field */
     skip_store_field= 1;
+  }
 
   // size/type should be changed
   if (change_field ||
       skip_store_field ||
       (new_type != item_type) ||
       (max_length < new_length) ||
-      ((new_type == INT_RESULT) &&
-       (decimals < item->decimals)) ||
       (!maybe_null && item->maybe_null) ||
       (item_type == STRING_RESULT && new_type == STRING_RESULT &&
        !my_charset_same(collation.collation, item->collation.collation)))
@@ -2556,8 +2547,6 @@ bool Item_type_holder::join_types(THD *thd, Item *item)
     // new field has some parameters worse then current
     skip_store_field|= (change_field &&
 			(max_length > new_length) ||
-			((new_type == INT_RESULT) &&
-			 (decimals > item->decimals)) ||
 			(maybe_null && !item->maybe_null) ||
 			(item_type == STRING_RESULT &&
 			 new_type == STRING_RESULT &&
diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
index 906ef646f47..3259e0a4f22 100644
--- a/sql/sql_derived.cc
+++ b/sql/sql_derived.cc
@@ -226,7 +226,7 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
   else
   {
     free_tmp_table(thd, table);
-    thd->lex->unit.cleanup();
+    unit->cleanup();
   }
 
 exit: