Bug#11714 Non-sensical ALTER TABLE ADD CONSTRAINT allowed

Bug#35578 Parser allows useless/illegal CREATE TABLE syntax
Bug#38696 CREATE TABLE ... CHECK ... allows illegal syntax

Backport from 6.0 to mysql-next-mr.

Author: Marc Alff

mysql-test/r/constraints.result

@@ -3,7 +3,7 @@ create table t1 (a int check (a>0));
 insert into t1 values (1);
 insert into t1 values (0);
 drop table t1;
-create table t1 (a int ,b int, check a>b);
+create table t1 (a int, b int, check (a>b));
 insert into t1 values (1,0);
 insert into t1 values (0,1);
 drop table t1;
@@ -27,3 +27,19 @@ t1	CREATE TABLE `t1` (
   UNIQUE KEY `key_2` (`a`)
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
+drop table if exists t_illegal;
+create table t_illegal (a int, b int, check a>b);
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a>b)' at line 1
+create table t_illegal (a int, b int, constraint abc check a>b);
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'a>b)' at line 1
+create table t_illegal (a int, b int, constraint abc);
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')' at line 1
+drop table if exists t_11714;
+create table t_11714(a int, b int);
+alter table t_11714 add constraint cons1;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
+drop table t_11714;
+CREATE TABLE t_illegal (col_1 INT CHECK something (whatever));
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'something (whatever))' at line 1
+CREATE TABLE t_illegal (col_1 INT CHECK something);
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'something)' at line 1

mysql-test/t/constraints.test

@@ -10,7 +10,7 @@ create table t1 (a int check (a>0));
 insert into t1 values (1);
 insert into t1 values (0);
 drop table t1;
-create table t1 (a int ,b int, check a>b);
+create table t1 (a int, b int, check (a>b));
 insert into t1 values (1,0);
 insert into t1 values (0,1);
 drop table t1;
@@ -29,3 +29,45 @@ show create table t1;
 drop table t1;
 
 # End of 4.1 tests
+
+#
+# Bug#35578 (Parser allows useless/illegal CREATE TABLE syntax)
+#
+
+--disable_warnings
+drop table if exists t_illegal;
+--enable_warnings
+
+--error ER_PARSE_ERROR
+create table t_illegal (a int, b int, check a>b);
+
+--error ER_PARSE_ERROR
+create table t_illegal (a int, b int, constraint abc check a>b);
+
+--error ER_PARSE_ERROR
+create table t_illegal (a int, b int, constraint abc);
+
+#
+# Bug#11714 (Non-sensical ALTER TABLE ADD CONSTRAINT allowed)
+#
+
+--disable_warnings
+drop table if exists t_11714;
+--enable_warnings
+
+create table t_11714(a int, b int);
+
+--error ER_PARSE_ERROR
+alter table t_11714 add constraint cons1;
+
+drop table t_11714;
+
+#
+# Bug#38696 (CREATE TABLE ... CHECK ... allows illegal syntax)
+
+--error ER_PARSE_ERROR
+CREATE TABLE t_illegal (col_1 INT CHECK something (whatever));
+
+--error ER_PARSE_ERROR
+CREATE TABLE t_illegal (col_1 INT CHECK something);
+

sql/sql_yacc.yy

@@ -765,10 +765,10 @@ bool my_yyoverflow(short **a, YYSTYPE **b, ulong *yystacksize);
 
 %pure_parser                                    /* We have threads */
 /*
-  Currently there are 172 shift/reduce conflicts.
+  Currently there are 169 shift/reduce conflicts.
   We should not introduce new conflicts any more.
 */
-%expect 172
+%expect 169
 
 /*
    Comments for TOKENS.
@@ -5282,10 +5282,6 @@ key_def:
             /* Only used for ALTER TABLE. Ignored otherwise. */
             lex->alter_info.flags|= ALTER_FOREIGN_KEY;
           }
-        | constraint opt_check_constraint
-          {
-            Lex->col_list.empty(); /* Alloced by sql_alloc */
-          }
         | opt_constraint check_constraint
           {
             Lex->col_list.empty(); /* Alloced by sql_alloc */
@@ -5298,7 +5294,7 @@ opt_check_constraint:
         ;
 
 check_constraint:
-          CHECK_SYM expr
+          CHECK_SYM '(' expr ')'
         ;
 
 opt_constraint: