Main patch MDEV-27896 Wrong result upon `COLLATE latin1_bin CHARACTER SET latin1` on the table or the database level

Also fixes
MDEV-27782 Wrong columns when using table level `CHARACTER SET utf8mb4 COLLATE DEFAULT`
MDEV-28644 Unexpected error on ALTER TABLE t1 CONVERT TO CHARACTER SET utf8mb3, DEFAULT CHARACTER SET utf8mb4

1 files changed, 51 insertions, 27 deletions

diff --git a/sql/handler.h b/sql/handler.h
index 036c4917b94..60c6195e68e 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -2289,33 +2289,6 @@ struct HA_CREATE_INFO: public Table_scope_and_contents_source_st,
     Schema_specification_st::init();
     alter_info= NULL;
   }
-  bool check_conflicting_charset_declarations(CHARSET_INFO *cs);
-  bool add_table_option_default_charset(CHARSET_INFO *cs)
-  {
-    // cs can be NULL, e.g.:  CREATE TABLE t1 (..) CHARACTER SET DEFAULT;
-    if (check_conflicting_charset_declarations(cs))
-      return true;
-    default_table_charset= cs;
-    used_fields|= HA_CREATE_USED_DEFAULT_CHARSET;
-    return false;
-  }
-  bool add_alter_list_item_convert_to_charset(CHARSET_INFO *cs)
-  {
-    /* 
-      cs cannot be NULL, as sql_yacc.yy translates
-         CONVERT TO CHARACTER SET DEFAULT
-      to
-         CONVERT TO CHARACTER SET <character-set-of-the-current-database>
-      TODO: Shouldn't we postpone resolution of DEFAULT until the
-      character set of the table owner database is loaded from its db.opt?
-    */
-    DBUG_ASSERT(cs);
-    if (check_conflicting_charset_declarations(cs))
-      return true;
-    alter_table_convert_to_charset= default_table_charset= cs;
-    used_fields|= (HA_CREATE_USED_CHARSET | HA_CREATE_USED_DEFAULT_CHARSET);  
-    return false;
-  }
   ulong table_options_with_row_type()
   {
     if (row_type == ROW_TYPE_DYNAMIC || row_type == ROW_TYPE_PAGE)
@@ -2323,6 +2296,10 @@ struct HA_CREATE_INFO: public Table_scope_and_contents_source_st,
     else
       return table_options;
   }
+  bool resolve_to_charset_collation_context(THD *thd,
+                  const Lex_table_charset_collation_attrs_st &default_cscl,
+                  const Lex_table_charset_collation_attrs_st &convert_cscl,
+                  const Charset_collation_context &ctx);
 };
 
 
@@ -2333,16 +2310,23 @@ struct HA_CREATE_INFO: public Table_scope_and_contents_source_st,
 struct Table_specification_st: public HA_CREATE_INFO,
                                public DDL_options_st
 {
+  Lex_table_charset_collation_attrs_st default_charset_collation;
+  Lex_table_charset_collation_attrs_st convert_charset_collation;
+
   // Deep initialization
   void init()
   {
     HA_CREATE_INFO::init();
     DDL_options_st::init();
+    default_charset_collation.init();
+    convert_charset_collation.init();
   }
   void init(DDL_options_st::Options options_arg)
   {
     HA_CREATE_INFO::init();
     DDL_options_st::init(options_arg);
+    default_charset_collation.init();
+    convert_charset_collation.init();
   }
   /*
     Quick initialization, for parser.
@@ -2354,6 +2338,46 @@ struct Table_specification_st: public HA_CREATE_INFO,
   {
     HA_CREATE_INFO::options= 0;
     DDL_options_st::init();
+    default_charset_collation.init();
+    convert_charset_collation.init();
+  }
+
+  bool add_table_option_convert_charset(CHARSET_INFO *cs)
+  {
+    // cs can be NULL, e.g.: ALTER TABLE t1 CONVERT TO CHARACTER SET DEFAULT;
+    used_fields|= (HA_CREATE_USED_CHARSET | HA_CREATE_USED_DEFAULT_CHARSET);
+    return cs ?
+      convert_charset_collation.merge_exact_charset(Lex_exact_charset(cs)) :
+      convert_charset_collation.merge_charset_default();
+  }
+  bool add_table_option_convert_collation(const Lex_extended_collation_st &cl)
+  {
+    used_fields|= (HA_CREATE_USED_CHARSET | HA_CREATE_USED_DEFAULT_CHARSET);
+    return convert_charset_collation.merge_collation(cl);
+  }
+
+  bool add_table_option_default_charset(CHARSET_INFO *cs)
+  {
+    // cs can be NULL, e.g.:  CREATE TABLE t1 (..) CHARACTER SET DEFAULT;
+    used_fields|= HA_CREATE_USED_DEFAULT_CHARSET;
+    return cs ?
+      default_charset_collation.merge_exact_charset(Lex_exact_charset(cs)) :
+      default_charset_collation.merge_charset_default();
+  }
+  bool add_table_option_default_collation(const Lex_extended_collation_st &cl)
+  {
+    used_fields|= HA_CREATE_USED_DEFAULT_CHARSET;
+    return default_charset_collation.merge_collation(cl);
+  }
+
+  bool resolve_to_charset_collation_context(THD *thd,
+                                         const Charset_collation_context &ctx)
+  {
+    return HA_CREATE_INFO::
+             resolve_to_charset_collation_context(thd,
+                                                  default_charset_collation,
+                                                  convert_charset_collation,
+                                                  ctx);
   }
 };