bzr commit into mysql-6.1-fk branch (dlenev:2686) WL#148

[Dmitry Lenev]

#At file:///home/dlenev/src/bzr/mysql-6.1-fk-mrg/

 2686 Dmitry Lenev	2008-10-18
      Got rid of extra shift/reduce conflicts and warnings about unused
      grammar rules which occured after merging recent changes from
      mysql-6.0 tree into tree for WL#148 "Foreign keys".
modified:
  sql/sql_yacc.yy

per-file messages:
  sql/sql_yacc.yy
    Got rid of extra shift/reduce conflicts which were caused by the
    fact that it was allowed to omit constraint identifier in DROP
    CONSTRAINT clause of ALTER TABLE (the conflict occured because
    for such grammar it is impossible to distinguish if REMOVE and
    PARTITION words following CONSTRAINT keyword are part of next
    clause of ALTER TABLE or a constraint name). Since omitting 
    constraint name in this situation is non-standard and does not
    make any sense we simply change grammar to disallow it.
    Also removed opt_check_constraint rule which is no longer
    used.
=== modified file 'sql/sql_yacc.yy'
--- a/sql/sql_yacc.yy	2008-10-10 08:21:42 +0000
+++ b/sql/sql_yacc.yy	2008-10-17 20:05:34 +0000
@@ -4945,11 +4945,6 @@ key_def:
           }
         ;
 
-opt_check_constraint:
-          /* empty */
-        | check_constraint
-        ;
-
 check_constraint:
           CHECK_SYM '(' expr ')'
         ;
@@ -6250,12 +6245,12 @@ alter_list_item:
             lex->alter_info.drop_list.push_back(ad);
             lex->alter_info.flags|= ALTER_DROP_COLUMN;
           }
-        | DROP constraint
+        | DROP CONSTRAINT field_ident
           {
             THD *thd= YYTHD;
             LEX *lex= thd->lex;
             Alter_drop *alter_drop=
-              new (thd->mem_root) Alter_drop(Alter_drop::FOREIGN_KEY, $2.str);
+              new (thd->mem_root) Alter_drop(Alter_drop::FOREIGN_KEY, $3.str);
             if (alter_drop == NULL)
               MYSQL_YYABORT;
             lex->alter_info.drop_list.push_back(alter_drop);