{"id":2448,"date":"2026-09-21T08:44:55","date_gmt":"2026-09-21T08:44:55","guid":{"rendered":"https:\/\/otus.ru\/journal\/?p=2448"},"modified":"2026-09-25T15:38:01","modified_gmt":"2026-09-25T15:38:01","slug":"java-i-bazy-dannyh-vse-ot-a-do-ya","status":"publish","type":"post","link":"https:\/\/otus.ru\/journal\/java-i-bazy-dannyh-vse-ot-a-do-ya\/","title":{"rendered":"\u0420\u0430\u0431\u043e\u0442\u0430 \u0441 \u0431\u0430\u0437\u0430\u043c\u0438 \u0434\u0430\u043d\u043d\u044b\u0445 \u0438\u0437 Java \u0447\u0435\u0440\u0435\u0437 JDBC"},"content":{"rendered":"

JDBC<\/strong> (Java Database Connectivity) — \u044d\u0442\u043e \u0441\u0442\u0430\u043d\u0434\u0430\u0440\u0442\u043d\u044b\u0439 API \u0438\u0437 \u043f\u0430\u043a\u0435\u0442\u0430 java.sql<\/code>, \u0447\u0435\u0440\u0435\u0437 \u043a\u043e\u0442\u043e\u0440\u044b\u0439 Java-\u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u0430 \u043f\u043e\u0434\u043a\u043b\u044e\u0447\u0430\u0435\u0442\u0441\u044f \u043a \u0440\u0435\u043b\u044f\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0411\u0414, \u043e\u0442\u043f\u0440\u0430\u0432\u043b\u044f\u0435\u0442 SQL-\u0437\u0430\u043f\u0440\u043e\u0441\u044b \u0438 \u0447\u0438\u0442\u0430\u0435\u0442 \u0440\u0435\u0437\u0443\u043b\u044c\u0442\u0430\u0442. \u041e\u043d \u0432\u0445\u043e\u0434\u0438\u0442 \u0432 Java SE \u0438 \u0440\u0430\u0431\u043e\u0442\u0430\u0435\u0442 \u043f\u043e\u0432\u0435\u0440\u0445 \u0434\u0440\u0430\u0439\u0432\u0435\u0440\u0430 \u043a\u043e\u043d\u043a\u0440\u0435\u0442\u043d\u043e\u0439 \u0421\u0423\u0411\u0414 (PostgreSQL, MySQL, Oracle). \u0412\u0430\u0436\u043d\u043e \u043f\u043e\u043d\u0438\u043c\u0430\u0442\u044c \u0433\u0440\u0430\u043d\u0438\u0446\u0443: JDBC \u0434\u0430\u0435\u0442 \u0435\u0434\u0438\u043d\u044b\u0439 \u0438\u043d\u0442\u0435\u0440\u0444\u0435\u0439\u0441 \u0434\u043b\u044f \u0440\u0430\u0431\u043e\u0442\u044b \u0441 \u0440\u0435\u043b\u044f\u0446\u0438\u043e\u043d\u043d\u044b\u043c\u0438 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0430\u043c\u0438, \u043f\u043e\u044d\u0442\u043e\u043c\u0443 \u043f\u0440\u0438 \u0441\u043c\u0435\u043d\u0435 \u0421\u0423\u0411\u0414 \u0441\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u0430 Java-\u043a\u043e\u0434\u0430 \u043e\u0431\u044b\u0447\u043d\u043e \u0441\u043e\u0445\u0440\u0430\u043d\u044f\u0435\u0442\u0441\u044f, \u043d\u043e \u043f\u0435\u0440\u0435\u043d\u043e\u0441\u0438\u0442\u0441\u044f \u043d\u0435 \u0432\u0441\u0435 — \u043c\u0435\u043d\u044f\u044e\u0442\u0441\u044f \u0434\u0440\u0430\u0439\u0432\u0435\u0440 \u0438 URL, \u0430 \u0432\u043c\u0435\u0441\u0442\u0435 \u0441 \u043d\u0438\u043c\u0438 \u043c\u043e\u0433\u0443\u0442 \u043f\u043e\u043c\u0435\u043d\u044f\u0442\u044c\u0441\u044f SQL-\u0434\u0438\u0430\u043b\u0435\u043a\u0442, \u043f\u043e\u0434\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u0435\u043c\u044b\u0435 \u0442\u0438\u043f\u044b, \u0441\u043f\u043e\u0441\u043e\u0431 \u043f\u043e\u043b\u0443\u0447\u0435\u043d\u0438\u044f \u0441\u0433\u0435\u043d\u0435\u0440\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u044b\u0445 \u043a\u043b\u044e\u0447\u0435\u0439 \u0438 \u0443\u0440\u043e\u0432\u043d\u0438 \u0438\u0437\u043e\u043b\u044f\u0446\u0438\u0438. \u0421\u043c\u0435\u043d\u0430 \u043e\u0434\u043d\u043e\u0439 \u0441\u0442\u0440\u043e\u043a\u0438 \u043f\u043e\u0434\u043a\u043b\u044e\u0447\u0435\u043d\u0438\u044f \u043f\u0435\u0440\u0435\u043d\u043e\u0441\u0438\u0442 \u043f\u0440\u0438\u043b\u043e\u0436\u0435\u043d\u0438\u0435 \u043d\u0435 \u0432\u0441\u0435\u0433\u0434\u0430: \u0441\u0430\u043c\u0438 \u0437\u0430\u043f\u0440\u043e\u0441\u044b \u0438 \u0441\u0445\u0435\u043c\u0430 \u043d\u0435\u0440\u0435\u0434\u043a\u043e \u0442\u0440\u0435\u0431\u0443\u044e\u0442 \u043f\u0440\u0430\u0432\u043e\u043a. \u0414\u0430\u043b\u044c\u0448\u0435 \u043f\u043e \u0442\u0435\u043a\u0441\u0442\u0443 \u044f \u043e\u0442\u043c\u0435\u0447\u0430\u044e, \u0447\u0442\u043e \u0438\u043c\u0435\u043d\u043d\u043e \u0433\u0430\u0440\u0430\u043d\u0442\u0438\u0440\u0443\u0435\u0442 \u0441\u0430\u043c API, \u0430 \u0447\u0442\u043e \u0437\u0430\u0432\u0438\u0441\u0438\u0442 \u043e\u0442 \u0434\u0440\u0430\u0439\u0432\u0435\u0440\u0430 \u0438 \u0421\u0423\u0411\u0414. \u041c\u0438\u043d\u0438\u043c\u0430\u043b\u044c\u043d\u044b\u0439 \u043f\u0440\u0438\u043c\u0435\u0440 \u043d\u0438\u0436\u0435 \u043d\u0430\u043f\u0438\u0441\u0430\u043d \u043f\u043e\u0434 PostgreSQL.<\/p>\n

\n

\u0421\u043e\u0434\u0435\u0440\u0436\u0430\u043d\u0438\u0435<\/strong><\/p>\n

    \n
  1. \u041c\u0438\u043d\u0438\u043c\u0430\u043b\u044c\u043d\u044b\u0439 \u0440\u0430\u0431\u043e\u0447\u0438\u0439 \u043f\u0440\u0438\u043c\u0435\u0440: \u0441\u043e\u0435\u0434\u0438\u043d\u0435\u043d\u0438\u0435 \u0438 \u0437\u0430\u043f\u0440\u043e\u0441<\/a><\/li>\n
  2. Statement \u0438 PreparedStatement: \u0432 \u0447\u0435\u043c \u0440\u0430\u0437\u043d\u0438\u0446\u0430<\/a><\/li>\n
  3. SQL-\u0438\u043d\u044a\u0435\u043a\u0446\u0438\u044f: \u043a\u0430\u043a \u043b\u043e\u043c\u0430\u0435\u0442\u0441\u044f \u043a\u043e\u043d\u043a\u0430\u0442\u0435\u043d\u0430\u0446\u0438\u044f \u0438 \u043a\u0430\u043a \u0447\u0438\u043d\u0438\u0442\u0441\u044f<\/a><\/li>\n
  4. \u041f\u0443\u043b \u0441\u043e\u0435\u0434\u0438\u043d\u0435\u043d\u0438\u0439: \u0437\u0430\u0447\u0435\u043c \u043d\u0443\u0436\u0435\u043d HikariCP<\/a><\/li>\n
  5. \u0422\u0440\u0430\u043d\u0437\u0430\u043a\u0446\u0438\u0438: \u0432\u0441\u0435 \u0438\u043b\u0438 \u043d\u0438\u0447\u0435\u0433\u043e<\/a><\/li>\n
  6. JDBC \u0438\u043b\u0438 ORM: \u0447\u0442\u043e \u0432\u044b\u0431\u0440\u0430\u0442\u044c<\/a><\/li>\n
  7. \u0412\u044b\u0432\u043e\u0434\u044b<\/a><\/li>\n
  8. \u0413\u0434\u0435 \u043f\u0440\u0438\u043c\u0435\u043d\u044f\u0435\u0442\u0441\u044f \/ \u0441\u0432\u044f\u0437\u044c \u0441 \u043f\u0440\u0430\u043a\u0442\u0438\u043a\u043e\u0439<\/a><\/li>\n
  9. FAQ<\/a><\/li>\n<\/ol>\n<\/div>\n

    \u041d\u0438\u0436\u0435 \u0440\u0430\u0437\u0431\u0435\u0440\u0435\u043c \u0440\u0430\u0431\u043e\u0447\u0438\u0439 \u0446\u0438\u043a\u043b: \u0441\u043e\u0435\u0434\u0438\u043d\u0435\u043d\u0438\u0435 \u0447\u0435\u0440\u0435\u0437 DriverManager<\/code>, \u0440\u0430\u0437\u043d\u0438\u0446\u0443 Statement<\/code> \u0438 PreparedStatement<\/code>, \u0437\u0430\u0449\u0438\u0442\u0443 \u043e\u0442 SQL-\u0438\u043d\u044a\u0435\u043a\u0446\u0438\u0439, \u043f\u0443\u043b HikariCP<\/code>, \u0442\u0440\u0430\u043d\u0437\u0430\u043a\u0446\u0438\u0438 \u0438 \u0442\u043e, \u043a\u043e\u0433\u0434\u0430 \u0432\u043c\u0435\u0441\u0442\u043e \u0447\u0438\u0441\u0442\u043e\u0433\u043e JDBC \u0431\u0435\u0440\u0443\u0442 ORM (JPA\/Hibernate).<\/p>\n

    \u041c\u0438\u043d\u0438\u043c\u0430\u043b\u044c\u043d\u044b\u0439 \u0440\u0430\u0431\u043e\u0447\u0438\u0439 \u043f\u0440\u0438\u043c\u0435\u0440: \u0441\u043e\u0435\u0434\u0438\u043d\u0435\u043d\u0438\u0435 \u0438 \u0437\u0430\u043f\u0440\u043e\u0441<\/h2>\n

    \u041d\u0430\u0447\u043d\u0435\u043c \u0441 \u0446\u0435\u043b\u043e\u0433\u043e \u043a\u0443\u0441\u043a\u0430, \u043a\u043e\u0442\u043e\u0440\u044b\u0439 \u043c\u043e\u0436\u043d\u043e \u0437\u0430\u043f\u0443\u0441\u0442\u0438\u0442\u044c, — \u043e\u043d \u043f\u043e\u0434\u043a\u043b\u044e\u0447\u0430\u0435\u0442\u0441\u044f \u043a PostgreSQL \u0438 \u043f\u0435\u0447\u0430\u0442\u0430\u0435\u0442 \u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u0435\u043b\u0435\u0439.<\/p>\n

    import<\/span> <\/span>java.sql.Connection<\/span>;<\/span>\nimport<\/span> <\/span>java.sql.DriverManager<\/span>;<\/span>\nimport<\/span> <\/span>java.sql.PreparedStatement<\/span>;<\/span>\nimport<\/span> <\/span>java.sql.ResultSet<\/span>;<\/span>\nimport<\/span> <\/span>java.sql.SQLException<\/span>;<\/span>\n\npublic<\/span> <\/span>class<\/span> UsersDemo<\/span> {<\/span>\n    <\/span>\/\/ URL, \u043b\u043e\u0433\u0438\u043d \u0438 \u043f\u0430\u0440\u043e\u043b\u044c \u043b\u0443\u0447\u0448\u0435 \u0431\u0440\u0430\u0442\u044c \u0438\u0437 \u043f\u0435\u0440\u0435\u043c\u0435\u043d\u043d\u044b\u0445 \u043e\u043a\u0440\u0443\u0436\u0435\u043d\u0438\u044f, \u0430 \u043d\u0435 \u0445\u0440\u0430\u043d\u0438\u0442\u044c \u0432 \u043a\u043e\u0434\u0435<\/span>\n    <\/span>static<\/span> <\/span>final<\/span> <\/span>String<\/span> <\/span>URL<\/span> <\/span>=<\/span> <\/span>System<\/span>.<\/span>getenv<\/span>(<\/span>\"DB_URL\"<\/span>);   <\/span>\/\/ jdbc:postgresql:\/\/localhost:5432\/shop<\/span>\n    <\/span>static<\/span> <\/span>final<\/span> <\/span>String<\/span> <\/span>USER<\/span> <\/span>=<\/span> <\/span>System<\/span>.<\/span>getenv<\/span>(<\/span>\"DB_USER\"<\/span>);<\/span>\n    <\/span>static<\/span> <\/span>final<\/span> <\/span>String<\/span> <\/span>PASSWORD<\/span> <\/span>=<\/span> <\/span>System<\/span>.<\/span>getenv<\/span>(<\/span>\"DB_PASSWORD\"<\/span>);<\/span>\n\n    <\/span>public<\/span> <\/span>static<\/span> <\/span>void<\/span> <\/span>main<\/span>(<\/span>String<\/span>[]<\/span> <\/span>args<\/span>) {<\/span>\n        <\/span>String<\/span> <\/span>sql<\/span> <\/span>=<\/span> <\/span>\"SELECT id, username FROM users WHERE id > ?\"<\/span>;<\/span>\n        <\/span>try<\/span> (<\/span>Connection<\/span> <\/span>conn<\/span> <\/span>=<\/span> <\/span>DriverManager<\/span>.<\/span>getConnection<\/span>(<\/span>URL<\/span>, <\/span>USER<\/span>, <\/span>PASSWORD<\/span>);<\/span>\n             <\/span>PreparedStatement<\/span> <\/span>ps<\/span> <\/span>=<\/span> <\/span>conn<\/span>.<\/span>prepareStatement<\/span>(<\/span>sql<\/span>)) {<\/span>\n\n            <\/span>ps<\/span>.<\/span>setInt<\/span>(<\/span>1<\/span>, <\/span>2<\/span>);                 <\/span>\/\/ \u043f\u043e\u0434\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u043c \u0437\u043d\u0430\u0447\u0435\u043d\u0438\u0435 \u0432 \u043f\u043b\u0435\u0439\u0441\u0445\u043e\u043b\u0434\u0435\u0440 ?<\/span>\n            <\/span>try<\/span> (<\/span>ResultSet<\/span> <\/span>rs<\/span> <\/span>=<\/span> <\/span>ps<\/span>.<\/span>executeQuery<\/span>()) {<\/span>\n                <\/span>while<\/span> (<\/span>rs<\/span>.<\/span>next<\/span>()) {          <\/span>\/\/ \u043a\u0443\u0440\u0441\u043e\u0440 \u0434\u0432\u0438\u0433\u0430\u0435\u0442\u0441\u044f \u043f\u043e \u0441\u0442\u0440\u043e\u043a\u0430\u043c \u0440\u0435\u0437\u0443\u043b\u044c\u0442\u0430\u0442\u0430<\/span>\n                    <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>rs<\/span>.<\/span>getInt<\/span>(<\/span>\"id\"<\/span>) <\/span>+<\/span> <\/span>\" \"<\/span> <\/span>+<\/span> <\/span>rs<\/span>.<\/span>getString<\/span>(<\/span>\"username\"<\/span>));<\/span>\n                }<\/span>\n            }<\/span>\n        } <\/span>catch<\/span> (<\/span>SQLException<\/span> <\/span>e<\/span>) {<\/span>\n            <\/span>System<\/span>.<\/span>out<\/span>.<\/span>println<\/span>(<\/span>\"\u041e\u0448\u0438\u0431\u043a\u0430 \u0411\u0414: \"<\/span> <\/span>+<\/span> <\/span>e<\/span>.<\/span>getMessage<\/span>());<\/span>\n        }<\/span>\n    }<\/span>\n}<\/span><\/code><\/pre>\n
    \u041e\u0436\u0438\u0434\u0430\u0435\u043c\u044b\u0439 \u0432\u044b\u0432\u043e\u0434 (\u043f\u0440\u0438 \u0442\u0440\u0435\u0445 \u0441\u0442\u0440\u043e\u043a\u0430\u0445 \u0432 \u0442\u0430\u0431\u043b\u0438\u0446\u0435 \u0441 id 1, 3, 5) — \u0434\u0432\u0435 \u0441\u0442\u0440\u043e\u043a\u0438, id 1 \u043e\u0442\u0444\u0438\u043b\u044c\u0442\u0440\u043e\u0432\u0430\u043d \u0443\u0441\u043b\u043e\u0432\u0438\u0435\u043c id > 2<\/code>:<\/p>\n
    3 petrov\n5 ivanov\n<\/code><\/pre>\n
    \u0427\u0442\u043e \u0437\u0434\u0435\u0441\u044c \u043f\u0440\u043e\u0438\u0441\u0445\u043e\u0434\u0438\u0442:<\/p>\n