Fix for #1189 (Mess with names about CONSTRAINT)

Second edition: error message was deleted as Segey suggested
Now name of the constraint will be used as the name of the key
if the last not specified


mysql-test/r/constraints.result:
  appropriate test result
mysql-test/t/constraints.test:
  test case for 1189
sql/sql_yacc.yy:
  language definitions changed so that we can obtaint constraint's name
  and send it as the name of the key if it's not specified

1 files changed, 6 insertions, 0 deletions

diff --git a/mysql-test/t/constraints.test b/mysql-test/t/constraints.test
index cc796e0abd2..dbc34a0dff1 100644
--- a/mysql-test/t/constraints.test
+++ b/mysql-test/t/constraints.test
@@ -21,3 +21,9 @@ drop table t1;
 create table t1 (a int null);
 insert into t1 values (1),(NULL);
 drop table t1;
+create table t1 (a int null);
+alter table t1 add constraint constraint_1 unique (a);
+alter table t1 add constraint unique key_1(a);
+alter table t1 add constraint constraint_2 unique key_2(a);
+show create table t1;
+drop table t1;