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+# ORM (RU)
+
+Легковесный ORM: поля мапятся в колонки, без сложных связей.
+Есть sync и async версии.
+
+## Аннотации
+
+- `@DbEntity(table = "players")` - имя таблицы. По умолчанию snake_case.
+- `@DbColumn(name = "username")` - имя колонки.
+- `@DbColumn(type = "VARCHAR(32)")` - SQL тип для генерации схемы.
+- `@DbColumn(length = 32, unique = true, nullable = false)` - влияет на schema генерацию.
+- `@DbId(autoIncrement = true)` - primary key.
+- `@DbJson` - JSON поле.
+- `@DbTransient` - игнорировать поле.
+
+## Пример сущности
+
+```java
+@DbEntity(table = "players")
+public class PlayerModel {
+    @DbId(autoIncrement = true)
+    private long id;
+
+    @DbColumn(name = "username", nullable = false, unique = true, length = 32)
+    private String name;
+
+    @DbColumn
+    private int level;
+
+    @DbJson
+    private java.util.Map<String, Object> metadata;
+
+    @DbTransient
+    private String temp;
+
+    public PlayerModel() {
+    }
+}
+```
+
+## CRUD
+
+```java
+EntityManager orm = api.orm();
+
+orm.insert(entity);
+orm.update(entity);
+orm.delete(entity);
+PlayerModel player = orm.findById(PlayerModel.class, 1L);
+List<PlayerModel> all = orm.findAll(PlayerModel.class);
+PlayerModel one = orm.findOneWhere(PlayerModel.class, "level >= ?", java.util.Collections.singletonList(10));
+List<PlayerModel> many = orm.findWhere(PlayerModel.class, "level >= ?", java.util.Collections.singletonList(10));
+List<PlayerModel> paged = orm.findWhere(PlayerModel.class, "level >= ?", java.util.Collections.singletonList(10), "level DESC", 10, 0);
+long count = orm.count(PlayerModel.class, "level >= ?", java.util.Collections.singletonList(10));
+boolean exists = orm.exists(PlayerModel.class, "username = ?", java.util.Collections.singletonList("Steve"));
+int deleted = orm.deleteWhere(PlayerModel.class, "level < ?", java.util.Collections.singletonList(1));
+```
+
+## Query Builder
+
+```java
+EntityManager orm = api.orm();
+
+List<PlayerModel> top = orm.query(PlayerModel.class)
+    .where("level >= ?", 10)
+    .orderBy("level DESC")
+    .limit(10)
+    .list();
+
+boolean exists = orm.query(PlayerModel.class)
+    .where("username = ?", "Steve")
+    .exists();
+```
+
+## Fluent Conditions
+
+```java
+import static com.andrewkydev.database.orm.Conditions.*;
+
+List<PlayerModel> players = orm.query(PlayerModel.class)
+    .where(eq("status", "ACTIVE").and(gt("level", 10)))
+    .list();
+```
+
+## Join, Group By, Having
+
+```java
+List<PlayerModel> rows = orm.query(PlayerModel.class)
+    .select("players.*")
+    .join("LEFT JOIN clans ON clans.id = players.clan_id")
+    .groupBy("players.id")
+    .having("COUNT(clans.id) > ?", 0)
+    .list();
+```
+
+Если выбрать часть колонок, маппятся только они, остальные остаются дефолтными.
+
+## Auto ID
+
+Если `@DbId(autoIncrement = true)` и id пустой (0/null),
+`insert()` получает generated keys и прописывает id в объект.
+
+## Type Adapters
+
+UUID уже поддержан. Для других типов:
+
+```java
+orm.registerAdapter(SomeType.class, new TypeAdapter<SomeType>() {
+    @Override
+    public Object toDatabase(SomeType value) {
+        return value == null ? null : value.toString();
+    }
+
+    @Override
+    public SomeType fromDatabase(Object value) {
+        return value == null ? null : SomeType.parse(value.toString());
+    }
+});
+```