Add inheritance example

7 files changed, 473 insertions, 1 deletions

diff --git a/README b/README
index e3b180a..b26034b 100644
--- a/README
+++ b/README
@@ -32,6 +32,9 @@ inverse
   Shows how to declare and use bidirectional one-to-one, one-to-many, and
   many-to-many relationships.
 
+inheritance
+  Shows how to use persistent class inheritance.
+
 boost
   Shows how to persist objects that use Boost smart pointers, containers,
   and value types with the help of the Boost profile library (libodb-boost).
diff --git a/inheritance/README b/inheritance/README
new file mode 100644
index 0000000..e1565b8
--- /dev/null
+++ b/inheritance/README
@@ -0,0 +1,55 @@
+This example shows how to use persistent class inheritance.
+
+The example consists of the following files:
+
+employee.hxx
+  Header file defining the 'person' and 'employee' abstract persistent
+  classes as well as the 'permanent_employee', 'temporary_employee', and
+  'contractor' concrete persistent classes.
+
+employee-odb.hxx
+employee-odb.ixx
+employee-odb.cxx
+employee.sql
+  The first three files contain the database support code and the last file
+  contains the database schema for the employee.hxx header.
+
+  These files are generated by the ODB compiler from employee.hxx using the
+  following command line:
+
+  odb -d <database> --generate-schema --generate-query employee.hxx
+
+  Where <database> stands for the database system we are using, for example,
+  'mysql'.
+
+database.hxx
+  Contains the create_database() function which instantiates the concrete
+  database class corresponding to the database system we are using.
+
+driver.cxx
+  Driver for the example. It includes the employee.hxx and employee-odb.hxx
+  headers to gain access to the persistent classes and their database support
+  code. It also includes database.hxx for the create_database() function
+  declaration.
+
+  In main() the driver first calls create_database() to obtain the database
+  instance. It then persists a number of permanent and temporary employee
+  objects as well as a number of contractor objects. The next transaction
+  looks up a contractor based on the email address. Finally, the driver
+  performs a database query which uses a data member from the base class
+  in its criterion.
+
+To run the example we may first need to create the database schema (for some
+database systems, such as SQLite, the schema is embedded into the generated
+code which makes this step unnecessary). Using MySQL as an example, this
+can be achieved with the following command:
+
+mysql --user=odb_test --database=odb_test < employee.sql
+
+Here we use 'odb_test' as the database login and also 'odb_test' as the
+database name.
+
+Once the database schema is ready, we can run the example (using MySQL as
+the database):
+
+./driver --user odb_test --database odb_test
diff --git a/inheritance/database.hxx b/inheritance/database.hxx
new file mode 100644
index 0000000..6d1fa66
--- /dev/null
+++ b/inheritance/database.hxx
@@ -0,0 +1,66 @@
+// file      : inheritance/database.hxx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : not copyrighted - public domain
+
+//
+// Create concrete database instance based on the DATABASE_* macros.
+//
+
+#ifndef DATABASE_HXX
+#define DATABASE_HXX
+
+#include <string>
+#include <memory>   // std::auto_ptr
+#include <cstdlib>  // std::exit
+#include <iostream>
+
+#include <odb/database.hxx>
+
+#if defined(DATABASE_MYSQL)
+#  include <odb/mysql/database.hxx>
+#elif defined(DATABASE_SQLITE)
+#  include <odb/transaction.hxx>
+#  include <odb/schema-catalog.hxx>
+#  include <odb/sqlite/database.hxx>
+#endif
+
+inline std::auto_ptr<odb::database>
+create_database (int& argc, char* argv[])
+{
+  using namespace std;
+  using namespace odb::core;
+
+  if (argc > 1 && argv[1] == string ("--help"))
+  {
+    cerr << "Usage: " << argv[0] << " [options]" << endl
+         << "Options:" << endl;
+
+#if defined(DATABASE_MYSQL)
+    odb::mysql::database::print_usage (cerr);
+#elif defined(DATABASE_SQLITE)
+    odb::sqlite::database::print_usage (cerr);
+#endif
+
+    exit (0);
+  }
+
+#if defined(DATABASE_MYSQL)
+  auto_ptr<database> db (new odb::mysql::database (argc, argv));
+#elif defined(DATABASE_SQLITE)
+  auto_ptr<database> db (
+    new odb::sqlite::database (
+      argc, argv, false, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE));
+
+  // Create the database schema.
+  //
+  {
+    transaction t (db->begin ());
+    schema_catalog::create_schema (*db);
+    t.commit ();
+  }
+#endif
+
+  return db;
+}
+
+#endif // DATABASE_HXX
diff --git a/inheritance/driver.cxx b/inheritance/driver.cxx
new file mode 100644
index 0000000..44fd721
--- /dev/null
+++ b/inheritance/driver.cxx
@@ -0,0 +1,82 @@
+// file      : inheritance/driver.cxx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : not copyrighted - public domain
+
+#include <memory>   // std::auto_ptr
+#include <iostream>
+
+#include <odb/database.hxx>
+#include <odb/transaction.hxx>
+
+#include "database.hxx" // create_database
+
+#include "employee.hxx"
+#include "employee-odb.hxx"
+
+using namespace std;
+using namespace odb::core;
+
+int
+main (int argc, char* argv[])
+{
+  try
+  {
+    auto_ptr<database> db (create_database (argc, argv));
+
+    // Add a few employees and contractors to the database.
+    //
+    {
+      permanent_employee p1 ("John", "Doe");
+      permanent_employee p2 ("Jane", "Doe");
+
+      temporary_employee t1 ("John", "Smith", 6);
+      temporary_employee t2 ("Jane", "Smith", 12);
+
+      contractor c1 ("Joe", "Doe", "j.doe@example.com");
+      contractor c2 ("Joe", "Smith", "j.smith@example.com");
+
+      transaction t (db->begin ());
+      db->persist (p1);
+      db->persist (p2);
+      db->persist (t1);
+      db->persist (t2);
+      db->persist (c1);
+      db->persist (c2);
+      t.commit ();
+    }
+
+    // Lookup a contractor based on the email address.
+    //
+    {
+      transaction t (db->begin ());
+      auto_ptr<contractor> c (db->load<contractor> ("j.smith@example.com"));
+      t.commit ();
+
+      cout << c->first () << " " << c->last () << " " << c->email () << endl;
+    }
+
+    // Query for temporary employees that have John as first name.
+    //
+    {
+      typedef odb::query<temporary_employee> query;
+      typedef odb::result<temporary_employee> result;
+
+      transaction t (db->begin ());
+
+      result r (db->query<temporary_employee> (query::first == "John"));
+
+      for (result::iterator i (r.begin ()); i != r.end (); ++i)
+      {
+        cout << i->first () << " " << i->last () << " "
+             << i->duration () << " months" << endl;
+      }
+
+      t.commit ();
+    }
+  }
+  catch (const odb::exception& e)
+  {
+    cerr << e.what () << endl;
+    return 1;
+  }
+}
diff --git a/inheritance/employee.hxx b/inheritance/employee.hxx
new file mode 100644
index 0000000..7b68b52
--- /dev/null
+++ b/inheritance/employee.hxx
@@ -0,0 +1,144 @@
+// file      : inheritance/employee.hxx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : not copyrighted - public domain
+
+#ifndef EMPLOYEE_HXX
+#define EMPLOYEE_HXX
+
+#include <string>
+
+#include <odb/core.hxx>
+
+// Abstract person class. Note that it does not declare the object id.
+//
+#pragma db object abstract
+class person
+{
+public:
+  person (const std::string& first, const std::string& last)
+      : first_ (first), last_ (last)
+  {
+  }
+
+  const std::string&
+  first () const
+  {
+    return first_;
+  }
+
+  const std::string&
+  last () const
+  {
+    return last_;
+  }
+
+protected:
+  friend class odb::access;
+  person () {}
+
+private:
+  std::string first_;
+  std::string last_;
+};
+
+// Abstract employee class. It derives from the person class and declares
+// the object id for all the concrete employee types.
+//
+#pragma db object abstract
+class employee: public person
+{
+public:
+  employee (const std::string& first, const std::string& last)
+      : person (first, last)
+  {
+  }
+
+  unsigned long
+  number () const
+  {
+    return id_;
+  }
+
+protected:
+  friend class odb::access;
+  employee () {}
+
+private:
+  #pragma db id auto
+  unsigned long id_;
+};
+
+// Concrete permanent_employee class. Note that it doesn't define any
+// data members of its own.
+//
+#pragma db object
+class permanent_employee: public employee
+{
+public:
+  permanent_employee (const std::string& first, const std::string& last)
+      : employee (first, last)
+  {
+  }
+
+private:
+  friend class odb::access;
+  permanent_employee () {}
+};
+
+// Concrete temporary_employee class. It adds the employment duration in
+// months.
+//
+#pragma db object
+class temporary_employee: public employee
+{
+public:
+  temporary_employee (const std::string& first,
+                      const std::string& last,
+                      unsigned long duration)
+      : employee (first, last), duration_ (duration)
+  {
+  }
+
+  unsigned long
+  duration () const
+  {
+    return duration_;
+  }
+
+private:
+  friend class odb::access;
+  temporary_employee () {}
+
+  unsigned long duration_;
+};
+
+// Concrete contractor class. It derives from the person class (and not
+// employee; an independent contractor is not considered an employee).
+// We use the contractor's external email address as the object id.
+//
+#pragma db object
+class contractor: public person
+{
+public:
+  contractor (const std::string& first,
+              const std::string& last,
+              const std::string& email)
+      : person (first, last), email_ (email)
+  {
+  }
+
+  const std::string&
+  email () const
+  {
+    return email_;
+  }
+
+private:
+  friend class odb::access;
+  contractor () {}
+
+  #pragma db id
+  std::string email_;
+};
+
+#endif // EMPLOYEE_HXX
diff --git a/inheritance/makefile b/inheritance/makefile
new file mode 100644
index 0000000..8c3aedc
--- /dev/null
+++ b/inheritance/makefile
@@ -0,0 +1,114 @@
+# file      : inheritance/makefile
+# author    : Boris Kolpackov <boris@codesynthesis.com>
+# copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+# license   : GNU GPL v2; see accompanying LICENSE file
+
+include $(dir $(lastword $(MAKEFILE_LIST)))../build/bootstrap.make
+
+cxx_tun := driver.cxx
+odb_hdr := employee.hxx
+cxx_obj := $(addprefix $(out_base)/,$(cxx_tun:.cxx=.o) $(odb_hdr:.hxx=-odb.o))
+cxx_od  := $(cxx_obj:.o=.o.d)
+
+driver  := $(out_base)/driver
+dist    := $(out_base)/.dist
+test    := $(out_base)/.test
+clean   := $(out_base)/.clean
+
+# Import.
+#
+$(call import,\
+  $(scf_root)/import/odb/stub.make,\
+  odb: odb,odb-rules: odb_rules)
+
+$(call import,\
+  $(scf_root)/import/libodb/stub.make,\
+  l: odb.l,cpp-options: odb.l.cpp-options)
+
+ifdef db_id
+$(call import,\
+  $(scf_root)/import/libodb-$(db_id)/stub.make,\
+  l: odb_db.l,cpp-options: odb_db.l.cpp-options)
+endif
+
+ifeq ($(odb_db.l.cpp-options),)
+odb_db.l.cpp-options := $(out_base)/.unbuildable
+endif
+
+# Build.
+#
+$(driver): $(cxx_obj) $(odb_db.l) $(odb.l)
+$(cxx_obj) $(cxx_od): cpp_options := -I$(out_base) -I$(src_base) -D$(db_macro)
+$(cxx_obj) $(cxx_od): $(odb.l.cpp-options) $(odb_db.l.cpp-options)
+
+genf := $(addprefix $(odb_hdr:.hxx=-odb),.hxx .ixx .cxx) $(odb_hdr:.hxx=.sql)
+gen  := $(addprefix $(out_base)/,$(genf))
+
+$(gen): $(odb)
+$(gen): odb := $(odb)
+$(gen) $(dist): export odb_options += --database $(db_id) --generate-schema \
+--generate-query
+$(gen): cpp_options := -I$(src_base)
+$(gen): $(odb.l.cpp-options)
+
+$(call include-dep,$(cxx_od),$(cxx_obj),$(gen))
+
+# Alias for default target.
+#
+$(out_base)/: $(driver)
+
+# Dist
+#
+name := $(subst /,-,$(subst $(src_root)/,,$(src_base)))
+
+$(dist): db_id := @database@
+$(dist): sources := $(cxx_tun)
+$(dist): headers := $(odb_hdr)
+$(dist): export name := $(name)
+$(dist): export odb_header_stem := $(basename $(odb_hdr))
+$(dist): export extra_dist := README $(call vc9projs,$(name)) \
+$(call vc10projs,$(name))
+$(dist):
+	$(call dist-data,$(sources) $(headers) README database.hxx)
+	$(call meta-automake,../template/Makefile.am)
+	$(call meta-vc9projs,../template/template,$(name))
+	$(call meta-vc10projs,../template/template,$(name))
+
+# Test.
+#
+$(test): header := $(odb_hdr)
+$(test): $(driver)
+	$(call schema)
+	$(call message,test $<,$< --options-file $(dcf_root)/db.options)
+
+# Clean.
+#
+$(clean):                            \
+  $(driver).o.clean                  \
+  $(addsuffix .cxx.clean,$(cxx_obj)) \
+  $(addsuffix .cxx.clean,$(cxx_od))  \
+  $(addprefix $(out_base)/,$(odb_hdr:.hxx=-odb.cxx.hxx.clean))
+
+# Generated .gitignore.
+#
+ifeq ($(out_base),$(src_base))
+$(driver): | $(out_base)/.gitignore
+
+$(out_base)/.gitignore: files := driver $(genf)
+$(clean): $(out_base)/.gitignore.clean
+
+$(call include,$(bld_root)/git/gitignore.make)
+endif
+
+# How to.
+#
+$(call include,$(bld_root)/dist.make)
+$(call include,$(bld_root)/meta/vc9proj.make)
+$(call include,$(bld_root)/meta/vc10proj.make)
+$(call include,$(bld_root)/meta/automake.make)
+
+$(call include,$(odb_rules))
+$(call include,$(bld_root)/cxx/cxx-d.make)
+$(call include,$(bld_root)/cxx/cxx-o.make)
+$(call include,$(bld_root)/cxx/o-e.make)
+
diff --git a/makefile b/makefile
index 79c200b..c47cd22 100644
--- a/makefile
+++ b/makefile
@@ -5,7 +5,15 @@
 
 include $(dir $(lastword $(MAKEFILE_LIST)))build/bootstrap.make
 
-dirs       := composite container hello query mapping schema/embedded
+dirs       :=   \
+composite       \
+container       \
+hello           \
+inheritance     \
+query           \
+mapping         \
+schema/embedded
+
 tr1_dirs   := relationship inverse schema/custom
 boost_dirs := boost
 qt_dirs    := qt