foreign_keys.h

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#ifndef DD_TABLES__FOREIGN_KEYS_INCLUDED
#define DD_TABLES__FOREIGN_KEYS_INCLUDED

#include "sql/dd/impl/types/object_table_impl.h"  // dd::Object_table_impl
#include "sql/dd/object_id.h"                     // dd::Object_id
#include "sql/dd/string_type.h"

struct CHARSET_INFO;

namespace dd {
class Object_key;

namespace tables {

///////////////////////////////////////////////////////////////////////////

class Foreign_keys : public Object_table_impl {
 public:
  static const Foreign_keys &instance();

  static const CHARSET_INFO *name_collation();

  enum enum_fields {
    FIELD_ID,
    FIELD_SCHEMA_ID,
    FIELD_TABLE_ID,
    FIELD_NAME,
    FIELD_UNIQUE_CONSTRAINT_NAME,
    FIELD_MATCH_OPTION,
    FIELD_UPDATE_RULE,
    FIELD_DELETE_RULE,
    FIELD_REFERENCED_TABLE_CATALOG,
    FIELD_REFERENCED_TABLE_SCHEMA,
    FIELD_REFERENCED_TABLE,
    FIELD_OPTIONS,
    NUMBER_OF_FIELDS  // Always keep this entry at the end of the enum
  };

  enum enum_indexes {
    INDEX_PK_ID = static_cast<uint>(Common_index::PK_ID),
    INDEX_UK_SCHEMA_ID_NAME = static_cast<uint>(Common_index::UK_NAME),
    INDEX_UK_TABLE_ID_NAME,
    INDEX_K_REF_CATALOG_REF_SCHEMA_REF_TABLE
  };

  enum enum_foreign_keys { FK_SCHEMA_ID };

  Foreign_keys();

  static Object_key *create_key_by_foreign_key_name(
      Object_id schema_id, const String_type &foreign_key_name);

  static Object_key *create_key_by_table_id(Object_id table_id);

  static Object_key *create_key_by_referenced_name(
      const String_type &referenced_catalog,
      const String_type &referenced_schema,
      const String_type &referenced_table);

  /**
    Check if schema contains foreign key with specified name.

    @param        thd               Thread context.
    @param        schema_id         Id of schema to be inspected.
    @param        foreign_key_name  Name of the foreign key.
    @param  [out] exists            Set to true if foreign key with
                                    the name provided exists in the
                                    schema, false otherwise.

    @retval      false    No error.
    @retval      true     Error.
  */

  static bool check_foreign_key_exists(THD *thd, Object_id schema_id,
                                       const String_type &foreign_key_name,
                                       bool *exists);
};

///////////////////////////////////////////////////////////////////////////

}  // namespace tables
}  // namespace dd

#endif  // DD_TABLES__FOREIGN_KEYS_INCLUDED