foreign_key.h

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   it under the terms of the GNU General Public License, version 2.0,
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
 
#ifndef DD__FOREIGN_KEY_INCLUDED
#define DD__FOREIGN_KEY_INCLUDED
 
#include "sql/dd/collection.h"           // dd::Collection
#include "sql/dd/sdi_fwd.h"              // dd::Sdi_wcontext
#include "sql/dd/types/entity_object.h"  // dd::Entity_object
#include "sql/dd/types/object_table.h"
 
namespace dd {
 
///////////////////////////////////////////////////////////////////////////
 
class Foreign_key_element;
class Foreign_key_impl;
class Index;
class Table;
 
namespace tables {
class Foreign_keys;
}
 
///////////////////////////////////////////////////////////////////////////
 
class Foreign_key : virtual public Entity_object {
 public:
  typedef Collection<Foreign_key_element *> Foreign_key_elements;
  typedef Foreign_key_impl Impl;
  typedef tables::Foreign_keys DD_table;
 
 public:
  enum enum_rule {
    RULE_NO_ACTION = 1,
    RULE_RESTRICT,
    RULE_CASCADE,
    RULE_SET_NULL,
    RULE_SET_DEFAULT
  };
 
  enum enum_match_option {
    OPTION_NONE = 1,
    OPTION_PARTIAL,
    OPTION_FULL,
  };
 
 public:
  ~Foreign_key() override = default;
 
  /////////////////////////////////////////////////////////////////////////
  // parent table.
  /////////////////////////////////////////////////////////////////////////
 
  virtual const Table &table() const = 0;
 
  virtual Table &table() = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // unique_constraint
  /////////////////////////////////////////////////////////////////////////
 
  // Note that setting "" as unique constraint name is interpreted as NULL
  // when storing this to the DD tables. And correspondingly, if NULL is
  // stored, and the dd::Foreign_key is fetched from the tables, then
  // unique_constraint_name() will return "".
 
  virtual const String_type &unique_constraint_name() const = 0;
  virtual void set_unique_constraint_name(const String_type &name) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // match_option.
  /////////////////////////////////////////////////////////////////////////
 
  virtual enum_match_option match_option() const = 0;
  virtual void set_match_option(enum_match_option match_option) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // update_rule.
  /////////////////////////////////////////////////////////////////////////
 
  virtual enum_rule update_rule() const = 0;
  virtual void set_update_rule(enum_rule update_rule) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // delete_rule.
  /////////////////////////////////////////////////////////////////////////
 
  virtual enum_rule delete_rule() const = 0;
  virtual void set_delete_rule(enum_rule delete_rule) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // the catalog name of the referenced table.
  /////////////////////////////////////////////////////////////////////////
 
  virtual const String_type &referenced_table_catalog_name() const = 0;
  virtual void set_referenced_table_catalog_name(const String_type &name) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // the schema name of the referenced table.
  /////////////////////////////////////////////////////////////////////////
 
  virtual const String_type &referenced_table_schema_name() const = 0;
  virtual void set_referenced_table_schema_name(const String_type &name) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // the name of the referenced table.
  /////////////////////////////////////////////////////////////////////////
 
  virtual const String_type &referenced_table_name() const = 0;
  virtual void set_referenced_table_name(const String_type &name) = 0;
 
  /////////////////////////////////////////////////////////////////////////
  // Foreign key element collection.
  /////////////////////////////////////////////////////////////////////////
 
  virtual Foreign_key_element *add_element() = 0;
 
  virtual const Foreign_key_elements &elements() const = 0;
 
  virtual Foreign_key_elements *elements() = 0;
 
  /**
    Converts *this into json.
 
    Converts all member variables that are to be included in the sdi
    into json by transforming them appropriately and passing them to
    the rapidjson writer provided.
 
    @param wctx opaque context for data needed by serialization
    @param w rapidjson writer which will perform conversion to json
 
  */
 
  virtual void serialize(Sdi_wcontext *wctx, Sdi_writer *w) const = 0;
 
  /**
    Re-establishes the state of *this by reading sdi information from
    the rapidjson DOM subobject provided.
 
    Cross-references encountered within this object are tracked in
    sdictx, so that they can be updated when the entire object graph
    has been established.
 
    @param rctx stores book-keeping information for the
    deserialization process
    @param val subobject of rapidjson DOM containing json
    representation of this object
    @retval false success
    @retval true  failure
  */
 
  virtual bool deserialize(Sdi_rcontext *rctx, const RJ_Value &val) = 0;
};
 
///////////////////////////////////////////////////////////////////////////
 
// Class to hold de-normalized information about FKs to be added
// to dd::Table objects representing FK parents.
 
class Foreign_key_parent {
 public:
  Foreign_key_parent()
      : m_child_schema_name(),
        m_child_table_name(),
        m_fk_name(),
        m_update_rule(Foreign_key::enum_rule::RULE_NO_ACTION),
        m_delete_rule(Foreign_key::enum_rule::RULE_NO_ACTION) {}
 
  const String_type &child_schema_name() const { return m_child_schema_name; }
 
  void set_child_schema_name(const String_type &child_schema_name) {
    m_child_schema_name = child_schema_name;
  }
 
  const String_type &child_table_name() const { return m_child_table_name; }
 
  void set_child_table_name(const String_type &child_table_name) {
    m_child_table_name = child_table_name;
  }
 
  const String_type &fk_name() const { return m_fk_name; }
 
  void set_fk_name(const String_type &fk_name) { m_fk_name = fk_name; }
 
  Foreign_key::enum_rule update_rule() const { return m_update_rule; }
 
  void set_update_rule(Foreign_key::enum_rule update_rule) {
    m_update_rule = update_rule;
  }
 
  Foreign_key::enum_rule delete_rule() const { return m_delete_rule; }
 
  void set_delete_rule(Foreign_key::enum_rule delete_rule) {
    m_delete_rule = delete_rule;
  }
 
 private:
  String_type m_child_schema_name;
  String_type m_child_table_name;
  String_type m_fk_name;
  Foreign_key::enum_rule m_update_rule;
  Foreign_key::enum_rule m_delete_rule;
};
 
///////////////////////////////////////////////////////////////////////////
 
}  // namespace dd
 
#endif  // DD__FOREIGN_KEY_INCLUDED