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Diffstat (limited to 'odb-examples/hello')
| -rw-r--r-- | odb-examples/hello/README | 63 | ||||
| -rw-r--r-- | odb-examples/hello/buildfile | 45 | ||||
| -rw-r--r-- | odb-examples/hello/database.hxx | 95 | ||||
| -rw-r--r-- | odb-examples/hello/driver.cxx | 130 | ||||
| -rw-r--r-- | odb-examples/hello/person.hxx | 73 | ||||
| -rw-r--r-- | odb-examples/hello/testscript | 13 |
6 files changed, 419 insertions, 0 deletions
diff --git a/odb-examples/hello/README b/odb-examples/hello/README new file mode 100644 index 0000000..bbe0942 --- /dev/null +++ b/odb-examples/hello/README @@ -0,0 +1,63 @@ +This is a "Hello World" example that shows how to use ODB to perform basic +database operations, such as making objects persistent, loading, updating +and deleting persistent objects, as well as querying the database for +objects matching a certain criteria. It also includes an example of a +simple view. + +The example consists of the following files: + +person.hxx + Header file defining the 'person' persistent class as well as the + 'person_stat' view. + +person-odb.hxx +person-odb.ixx +person-odb.cxx +person.sql + The first three files contain the database support code and the last file + contains the database schema for the person.hxx header. + + These files are generated by the ODB compiler from person.hxx using the + following command line: + + odb --std c++11 -d <database> --generate-query --generate-schema person.hxx + + Where <database> stands for the database system we are using, for example, + 'pgsql'. + +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 person.hxx and person-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. Then it executes a number of database transactions on persistent + objects. + +To compile and link the example manually from the command line we can use the +following commands (using PostgreSQL as an example; replace 'c++' with your +C++ compiler name): + +c++ -c person-odb.cxx +c++ -DDATABASE_PGSQL -c driver.cxx +c++ -o driver driver.o person-odb.o -lodb-pgsql -lodb + +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 PostgreSQL as an example, this +can be achieved with the following command: + +psql --username=odb_test --dbname=odb_test -f person.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 PostgreSQL as +the database): + +./driver --user odb_test --database odb_test diff --git a/odb-examples/hello/buildfile b/odb-examples/hello/buildfile new file mode 100644 index 0000000..e6ad903 --- /dev/null +++ b/odb-examples/hello/buildfile @@ -0,0 +1,45 @@ +# file : hello/buildfile +# license : GNU GPL v2; see accompanying LICENSE file + +import libodb = libodb%lib{odb} + +import libs = libodb-$database%lib{odb-$database} + +exe{driver}: {hxx cxx}{* -person-odb} {hxx ixx cxx}{person-odb} testscript + +# The metadata library target which we use to extract the poptions variable +# value for specifying the preprocessor options (-I, etc) on the ODB compiler +# command line. +# +libue{person-meta}: $libodb + +exe{driver}: libue{person-meta} $libs + +<{hxx ixx cxx}{person-odb}>: hxx{person} libue{person-meta} $odb +{{ + pops = $cxx.lib_poptions($<[1]) + depdb hash $pops + + depdb dyndep --dyn-target --target-what 'generated schema' --format lines \ + -- echo ($sqlite ? '' : "$out_base/person.sql") + + $odb --std c++11 \ + --database $database \ + --generate-schema \ + --generate-query \ + --output-dir $out_base \ + --table-prefix hello_ \ + "-I$src_base" $pops \ + $path($<[0]) +}} + +cxx.poptions =+ "-I$out_base" "-I$src_base" -DDATABASE_$ucase($database) + +# Testscript's run-time prerequisites. +# +# @@ BUILD2: Eventually we should be able to mark it as test.input once +# this is supported for testscript tests. +# +exe{driver}: ../alias{database-client}: include = adhoc + +testscript@./: schema = person diff --git a/odb-examples/hello/database.hxx b/odb-examples/hello/database.hxx new file mode 100644 index 0000000..cdfc033 --- /dev/null +++ b/odb-examples/hello/database.hxx @@ -0,0 +1,95 @@ +// file : hello/database.hxx +// 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::unique_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/connection.hxx> +# include <odb/transaction.hxx> +# include <odb/schema-catalog.hxx> +# include <odb/sqlite/database.hxx> +#elif defined(DATABASE_PGSQL) +# include <odb/pgsql/database.hxx> +#elif defined(DATABASE_ORACLE) +# include <odb/oracle/database.hxx> +#elif defined(DATABASE_MSSQL) +# include <odb/mssql/database.hxx> +#else +# error unknown database; did you forget to define the DATABASE_* macros? +#endif + +inline std::unique_ptr<odb::database> +create_database (int& argc, char* argv[]) +{ + using namespace std; + using namespace odb::core; + + if (argc > 1 && argv[1] == string ("--help")) + { + cout << "Usage: " << argv[0] << " [options]" << endl + << "Options:" << endl; + +#if defined(DATABASE_MYSQL) + odb::mysql::database::print_usage (cout); +#elif defined(DATABASE_SQLITE) + odb::sqlite::database::print_usage (cout); +#elif defined(DATABASE_PGSQL) + odb::pgsql::database::print_usage (cout); +#elif defined(DATABASE_ORACLE) + odb::oracle::database::print_usage (cout); +#elif defined(DATABASE_MSSQL) + odb::mssql::database::print_usage (cout); +#endif + + exit (0); + } + +#if defined(DATABASE_MYSQL) + unique_ptr<database> db (new odb::mysql::database (argc, argv)); +#elif defined(DATABASE_SQLITE) + unique_ptr<database> db ( + new odb::sqlite::database ( + argc, argv, false, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE)); + + // Create the database schema. Due to bugs in SQLite foreign key + // support for DDL statements, we need to temporarily disable + // foreign keys. + // + { + connection_ptr c (db->connection ()); + + c->execute ("PRAGMA foreign_keys=OFF"); + + transaction t (c->begin ()); + schema_catalog::create_schema (*db); + t.commit (); + + c->execute ("PRAGMA foreign_keys=ON"); + } +#elif defined(DATABASE_PGSQL) + unique_ptr<database> db (new odb::pgsql::database (argc, argv)); +#elif defined(DATABASE_ORACLE) + unique_ptr<database> db (new odb::oracle::database (argc, argv)); +#elif defined(DATABASE_MSSQL) + unique_ptr<database> db ( + new odb::mssql::database (argc, argv, false, "TrustServerCertificate=yes")); +#endif + + return db; +} + +#endif // DATABASE_HXX diff --git a/odb-examples/hello/driver.cxx b/odb-examples/hello/driver.cxx new file mode 100644 index 0000000..175ced1 --- /dev/null +++ b/odb-examples/hello/driver.cxx @@ -0,0 +1,130 @@ +// file : hello/driver.cxx +// copyright : not copyrighted - public domain + +#include <memory> // std::unique_ptr +#include <iostream> + +#include <odb/database.hxx> +#include <odb/transaction.hxx> + +#include "database.hxx" // create_database + +#include "person.hxx" +#include "person-odb.hxx" + +using namespace std; +using namespace odb::core; + +int +main (int argc, char* argv[]) +{ + try + { + unique_ptr<database> db (create_database (argc, argv)); + + unsigned long john_id, joe_id; + + // Create a few persistent person objects. + // + { + person john ("John", "Doe", 33); + person jane ("Jane", "Doe", 32); + person joe ("Joe", "Dirt", 30); + + transaction t (db->begin ()); + + // Make objects persistent and save their ids for later use. + // + john_id = db->persist (john); + db->persist (jane); + joe_id = db->persist (joe); + + t.commit (); + } + + typedef odb::query<person> query; + typedef odb::result<person> result; + + // Say hello to those over 30. + // + { + transaction t (db->begin ()); + + result r (db->query<person> (query::age > 30)); + + for (result::iterator i (r.begin ()); i != r.end (); ++i) + { + cout << "Hello, " << i->first () << " " << i->last () << "!" << endl; + } + + t.commit (); + } + + // Joe Dirt just had a birthday, so update his age. + // + { + transaction t (db->begin ()); + + unique_ptr<person> joe (db->load<person> (joe_id)); + joe->age (joe->age () + 1); + db->update (*joe); + + t.commit (); + } + + // Alternative implementation without using the id. + // + /* + { + transaction t (db->begin ()); + + // Here we know that there can be only one Joe Dirt in our + // database so we use the query_one() shortcut instead of + // manually iterating over the result returned by query(). + // + unique_ptr<person> joe ( + db->query_one<person> (query::first == "Joe" && + query::last == "Dirt")); + + if (joe.get () != 0) + { + joe->age (joe->age () + 1); + db->update (*joe); + } + + t.commit (); + } + */ + + // Print some statistics about all the people in our database. + // + { + transaction t (db->begin ()); + + // The result of this (aggregate) query always has exactly one element + // so use the query_value() shortcut. + // + person_stat ps (db->query_value<person_stat> ()); + + cout << endl + << "count : " << ps.count << endl + << "min age: " << ps.min_age << endl + << "max age: " << ps.max_age << endl; + + t.commit (); + } + + // John Doe is no longer in our database. + // + { + transaction t (db->begin ()); + db->erase<person> (john_id); + t.commit (); + } + } + catch (const odb::exception& e) + { + cerr << e.what () << endl; + return 1; + } +} diff --git a/odb-examples/hello/person.hxx b/odb-examples/hello/person.hxx new file mode 100644 index 0000000..81a9321 --- /dev/null +++ b/odb-examples/hello/person.hxx @@ -0,0 +1,73 @@ +// file : hello/person.hxx +// copyright : not copyrighted - public domain + +#ifndef PERSON_HXX +#define PERSON_HXX + +#include <string> +#include <cstddef> // std::size_t + +#include <odb/core.hxx> + +#pragma db object +class person +{ +public: + person (const std::string& first, + const std::string& last, + unsigned short age) + : first_ (first), last_ (last), age_ (age) + { + } + + const std::string& + first () const + { + return first_; + } + + const std::string& + last () const + { + return last_; + } + + unsigned short + age () const + { + return age_; + } + + void + age (unsigned short age) + { + age_ = age; + } + +private: + friend class odb::access; + + person () {} + + #pragma db id auto + unsigned long id_; + + std::string first_; + std::string last_; + unsigned short age_; +}; + +#pragma db view object(person) +struct person_stat +{ + #pragma db column("count(" + person::id_ + ")") + std::size_t count; + + #pragma db column("min(" + person::age_ + ")") + unsigned short min_age; + + #pragma db column("max(" + person::age_ + ")") + unsigned short max_age; +}; + +#endif // PERSON_HXX diff --git a/odb-examples/hello/testscript b/odb-examples/hello/testscript new file mode 100644 index 0000000..2d72ba5 --- /dev/null +++ b/odb-examples/hello/testscript @@ -0,0 +1,13 @@ +# file : hello/testscript +# license : GNU GPL v2; see accompanying LICENSE file + +.include ../database-options.testscript +.include ../$(database).testscript + ++if! $sqlite + $create_schema +end + +: basics +: +$* >| |