Bug#5507: TRUNCATE does not work with views.

Support of views wasn't implemented for the TRUNCATE statement.
Now TRUNCATE on views has the same semantics as DELETE FROM view:
mysql_truncate() checks whether the table is a view and falls back
to delete if so.
In order to initialize properly the LEX::updatable for a view
st_lex::can_use_merged() now allows usage of merged views for the
TRUNCATE statement.


mysql-test/r/truncate.result:
  Added a test case for the Bug#5507: TRUNCATE does not work with views.
mysql-test/t/truncate.test:
  Added a test case for the Bug#5507: TRUNCATE does not work with views.
sql/sql_lex.cc:
  Bug#5507: TRUNCATE does not work with views.
  can_use_merged() was denying of usage of merged views for a
  TRUNCATE statement. This results in improper initialization
  of view LEX::updatable. Fixed.
sql/sql_delete.cc:
  Bug#5507: TRUNCATE does not work with views.
  1.mysql_truncate() was lacking of check whether the table is view. Added.
  2.mysql_truncate() calls mysql_delete(), but mysql_delete() always reports
  errors as "DELETE" errors. Fixed.
mysql-test/t/view.test:
  Updated test case for Bug#14540: OPTIMIZE, ANALYZE, REPAIR applied 
  to not a view.
mysql-test/r/view.result:
  Updated test case for Bug#14540: OPTIMIZE, ANALYZE, REPAIR applied 
  to not a view.

1 files changed, 27 insertions, 0 deletions

diff --git a/mysql-test/r/truncate.result b/mysql-test/r/truncate.result
index 74a6cb72cc6..6c21db0e2b8 100644
--- a/mysql-test/r/truncate.result
+++ b/mysql-test/r/truncate.result
@@ -53,3 +53,30 @@ a
 3
 4
 drop table t1;
+create table t1 (s1 int);
+insert into t1 (s1) values (1), (2), (3), (4), (5);
+create view v1 as select * from t1;
+truncate table v1;
+select count(*) from t1;
+count(*)
+0
+insert into t1 (s1) values (1), (2), (3), (4), (5);
+create view v2 as select * from t1 where s1 > 3;
+truncate table v2;
+select * from t1;
+s1
+1
+2
+3
+select * from v2;
+s1
+delete from t1;
+create table t2 (s1 int, s2 int);
+create view v3 as select a.s1, b.s2 from t1 a join t2 b on a.s1 = b.s1 where a.s1 > 3;
+truncate table v3;
+ERROR HY000: Can not delete from join view 'test.v3'
+create view v4 as select * from t1 limit 1,1;
+truncate table v4;
+ERROR HY000: The target table v4 of the TRUNCATE is not updatable
+drop view v1, v2, v3, v4;
+drop table t1, t2;