MDEV-20729 Fix REFERENCES constraint in column definition

Add support of referential constraints directly in column defininions:

create table t1 (id1 int primary key);
create table t2 (id2 int references t1(id1));

Referenced field name can be omitted if equal to foreign field name:

create table t1 (id int primary key);
create table t2 (id int references t1);

Until 10.5 this syntax was understood by the parser but was silently
ignored.

In case of generated columns this syntax is disabled at parser level
by ER_PARSE_ERROR. Note that separate FOREIGN KEY clause for generated
columns is disabled at storage engine level.

1 files changed, 9 insertions, 0 deletions

diff --git a/sql/sql_lex.h b/sql/sql_lex.h
index 4abc7dde940..0c3108e8ebe 100644
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -4613,6 +4613,15 @@ public:
                          const LEX_CSTRING &name);
 
   void mark_first_table_as_inserting();
+
+  bool add_table_foreign_key(const LEX_CSTRING *name,
+                             const LEX_CSTRING *constraint_name,
+                             Table_ident *table_name,
+                             DDL_options ddl_options);
+  bool add_column_foreign_key(const LEX_CSTRING *name,
+                              const LEX_CSTRING *constraint_name,
+                              Table_ident *ref_table_name,
+                              DDL_options ddl_options);
 };