merge on pull

BitKeeper/etc/logging_ok:
  auto-union
BitKeeper/deleted/.del-Makefile.am:
  Delete: Docs/Images/Makefile.am
configure.in:
  Auto merged
innobase/include/row0mysql.h:
  Auto merged
innobase/lock/lock0lock.c:
  Auto merged
innobase/row/row0mysql.c:
  Auto merged
mysql-test/r/ps.result:
  Auto merged
mysql-test/t/ps.test:
  Auto merged
sql/ha_innodb.cc:
  Auto merged
sql/ha_innodb.h:
  Auto merged
sql/item.cc:
  Auto merged
sql/item.h:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/table.cc:
  Auto merged

1 files changed, 26 insertions, 3 deletions

diff --git a/sql/item.h b/sql/item.h
index eed0b065a83..93c396b95b0 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -38,6 +38,25 @@ enum Derivation
   DERIVATION_EXPLICIT= 0
 };
 
+/*
+  Flags for collation aggregation modes:
+  MY_COLL_ALLOW_SUPERSET_CONV  - allow conversion to a superset
+  MY_COLL_ALLOW_COERCIBLE_CONV - allow conversion of a coercible value
+                                 (i.e. constant).
+  MY_COLL_ALLOW_CONV           - allow any kind of conversion
+                                 (combintion of the above two)
+  MY_COLL_DISALLOW_NONE        - don't allow return DERIVATION_NONE
+                                 (e.g. when aggregating for comparison)
+  MY_COLL_CMP_CONV             - combination of MY_COLL_ALLOW_CONV
+                                 and MY_COLL_DISALLOW_NONE
+*/
+
+#define MY_COLL_ALLOW_SUPERSET_CONV   1
+#define MY_COLL_ALLOW_COERCIBLE_CONV  2
+#define MY_COLL_ALLOW_CONV            3
+#define MY_COLL_DISALLOW_NONE         4
+#define MY_COLL_CMP_CONV              7
+
 class DTCollation {
 public:
   CHARSET_INFO     *collation;
@@ -73,9 +92,9 @@ public:
   { collation= collation_arg; }
   void set(Derivation derivation_arg)
   { derivation= derivation_arg; }
-  bool aggregate(DTCollation &dt, bool superset_conversion= FALSE);
-  bool set(DTCollation &dt1, DTCollation &dt2, bool superset_conversion= FALSE)
-  { set(dt1); return aggregate(dt2, superset_conversion); }
+  bool aggregate(DTCollation &dt, uint flags= 0);
+  bool set(DTCollation &dt1, DTCollation &dt2, uint flags= 0)
+  { set(dt1); return aggregate(dt2, flags); }
   const char *derivation_name() const
   {
     switch(derivation)
@@ -306,6 +325,7 @@ public:
   virtual Item_field *filed_for_view_update() { return 0; }
 
   virtual Item *neg_transformer(THD *thd) { return NULL; }
+  virtual Item *safe_charset_converter(CHARSET_INFO *tocs);
   void delete_self()
   {
     cleanup();
@@ -542,6 +562,7 @@ public:
   bool replace_equal_field_processor(byte *arg);
   inline uint32 max_disp_length() { return field->max_length(); }
   Item_field *filed_for_view_update() { return this; }
+  Item *safe_charset_converter(CHARSET_INFO *tocs);
   friend class Item_default_value;
   friend class Item_insert_value;
   friend class st_select_lex_unit;
@@ -573,6 +594,7 @@ public:
   Item *new_item() { return new Item_null(name); }
   bool is_null() { return 1; }
   void print(String *str) { str->append("NULL", 4); }
+  Item *safe_charset_converter(CHARSET_INFO *tocs);
 };
 
 
@@ -862,6 +884,7 @@ public:
     return new Item_string(name, str_value.ptr(), 
     			   str_value.length(), &my_charset_bin);
   }
+  Item *safe_charset_converter(CHARSET_INFO *tocs);
   String *const_string() { return &str_value; }
   inline void append(char *str, uint length) { str_value.append(str, length); }
   void print(String *str);