Bug #28702: VIEWs defined with USE/FORCE KEY ignore that request

When storing the VIEW the CREATE VIEW command is reconstructed 
from the parse tree. While constructing the command string
the index hints specified should also be printed.
Fixed by adding code to print the index hints when printing a 
table in the FROM clause.


mysql-test/r/view.result:
  Bug #28702: test case
mysql-test/t/view.test:
  Bug #28702: test case
sql/sql_select.cc:
  Bug #28702: preserve index hints in a VIEW definition.
sql/table.h:
  Bug #28702: preserve index hints in a VIEW definition.

mysql-test/r/view.result

@@ -3573,4 +3573,32 @@ SELECT * FROM v1 IGNORE KEY(non_existant);
 ERROR HY000: Incorrect usage of IGNORE INDEX and VIEW
 DROP VIEW v1;
 DROP TABLE t1;
+CREATE TABLE t1 (a INT NOT NULL AUTO_INCREMENT, b INT NOT NULL DEFAULT 0,
+PRIMARY KEY(a), KEY (b));
+INSERT INTO t1 VALUES (),(),(),(),(),(),(),(),(),(),(),(),(),(),();
+CREATE VIEW v1 AS SELECT * FROM t1 FORCE KEY (PRIMARY,b) ORDER BY a;
+SHOW CREATE VIEW v1;
+View	Create View
+v1	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v1` AS select `t1`.`a` AS `a`,`t1`.`b` AS `b` from `t1` FORCE INDEX (PRIMARY,`b`) order by `t1`.`a`
+EXPLAIN SELECT * FROM v1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	NULL	PRIMARY	4	NULL	15	
+CREATE VIEW v2 AS SELECT * FROM t1 USE KEY () ORDER BY a;
+SHOW CREATE VIEW v2;
+View	Create View
+v2	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v2` AS select `t1`.`a` AS `a`,`t1`.`b` AS `b` from `t1` USE INDEX () order by `t1`.`a`
+EXPLAIN SELECT * FROM v2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	15	Using filesort
+CREATE VIEW v3 AS SELECT * FROM t1 IGNORE KEY (b) ORDER BY a;
+SHOW CREATE VIEW v3;
+View	Create View
+v3	CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v3` AS select `t1`.`a` AS `a`,`t1`.`b` AS `b` from `t1` IGNORE INDEX (`b`) order by `t1`.`a`
+EXPLAIN SELECT * FROM v3;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	15	Using filesort
+DROP VIEW v1;
+DROP VIEW v2;
+DROP VIEW v3;
+DROP TABLE t1;
 End of 5.0 tests.

mysql-test/t/view.test

@@ -3434,5 +3434,26 @@ DROP VIEW v1;
 DROP TABLE t1;
 
 
+#
+# Bug #28702: VIEWs defined with USE/FORCE KEY ignore that request
+#
+CREATE TABLE t1 (a INT NOT NULL AUTO_INCREMENT, b INT NOT NULL DEFAULT 0,
+                 PRIMARY KEY(a), KEY (b));
+INSERT INTO t1 VALUES (),(),(),(),(),(),(),(),(),(),(),(),(),(),();
+CREATE VIEW v1 AS SELECT * FROM t1 FORCE KEY (PRIMARY,b) ORDER BY a;
+SHOW CREATE VIEW v1;
+EXPLAIN SELECT * FROM v1;
+CREATE VIEW v2 AS SELECT * FROM t1 USE KEY () ORDER BY a;
+SHOW CREATE VIEW v2;
+EXPLAIN SELECT * FROM v2;
+CREATE VIEW v3 AS SELECT * FROM t1 IGNORE KEY (b) ORDER BY a;
+SHOW CREATE VIEW v3;
+EXPLAIN SELECT * FROM v3;
+
+DROP VIEW v1;
+DROP VIEW v2;
+DROP VIEW v3;
+DROP TABLE t1;
+
 --echo End of 5.0 tests.
 

sql/sql_select.cc

@@ -15469,6 +15469,47 @@ static void print_join(THD *thd, String *str, List<TABLE_LIST> *tables)
 }
 
 
+/**
+  @brief Print an index hint for a table
+
+  @details Prints out the USE|FORCE|IGNORE index hints for a table.
+
+  @param      thd         the current thread
+  @param[out] str         appends the index hint here
+  @param      hint        what the hint is (as string : "USE INDEX"|
+                          "FORCE INDEX"|"IGNORE INDEX")
+  @param      hint_length the length of the string in 'hint'
+  @param      indexes     a list of index names for the hint
+*/
+
+void 
+TABLE_LIST::print_index_hint(THD *thd, String *str, 
+                                const char *hint, uint32 hint_length,
+                                List<String> indexes)
+{
+  List_iterator_fast<String> li(indexes);
+  String *idx;
+  bool first= 1;
+
+  str->append (' ');
+  str->append (hint, hint_length);
+  str->append (STRING_WITH_LEN(" ("));
+  while ((idx = li++))
+  {
+    if (first)
+      first= 0;
+    else
+      str->append(',');
+    if (!my_strcasecmp (system_charset_info, idx->c_ptr_safe(), 
+                        primary_key_name))
+      str->append(primary_key_name);
+    else
+      append_identifier (thd, str, idx->ptr(), idx->length());
+  }
+  str->append(')');
+}
+
+
 /*
   Print table as it should be in join list
 
@@ -15536,6 +15577,17 @@ void TABLE_LIST::print(THD *thd, String *str)
       str->append(' ');
       append_identifier(thd, str, alias, strlen(alias));
     }
+
+    if (use_index)
+    {
+      if (force_index)
+        print_index_hint(thd, str, STRING_WITH_LEN("FORCE INDEX"), *use_index);
+      else
+        print_index_hint(thd, str, STRING_WITH_LEN("USE INDEX"), *use_index);
+    }
+    if (ignore_index)
+      print_index_hint (thd, str, STRING_WITH_LEN("IGNORE INDEX"), *ignore_index);
+
   }
 }
 

sql/table.h

@@ -773,6 +773,8 @@ struct TABLE_LIST
 private:
   bool prep_check_option(THD *thd, uint8 check_opt_type);
   bool prep_where(THD *thd, Item **conds, bool no_where_clause);
+  void print_index_hint(THD *thd, String *str, const char *hint, 
+                        uint32 hint_length, List<String>);
   /*
     Cleanup for re-execution in a prepared statement or a stored
     procedure.