Fix: Find one with join issue

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/Author.java

@@ -0,0 +1,18 @@
+package io.micronaut.data.jdbc.h2.joinissue;
+
+import io.micronaut.data.annotation.GeneratedValue;
+import io.micronaut.data.annotation.Id;
+import io.micronaut.data.annotation.MappedEntity;
+import io.micronaut.data.annotation.Relation;
+
+import java.util.Set;
+
+@MappedEntity("ji_author")
+public record Author(
+        @Id
+        @GeneratedValue
+        Long id,
+        String name,
+        @Relation(value = Relation.Kind.ONE_TO_MANY, cascade = Relation.Cascade.ALL, mappedBy = "author")
+        Set<Book> books) {
+}

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/AuthorRepository.java

@@ -0,0 +1,39 @@
+package io.micronaut.data.jdbc.h2.joinissue;
+
+import io.micronaut.data.annotation.Join;
+import io.micronaut.data.annotation.Query;
+import io.micronaut.data.jdbc.annotation.JdbcRepository;
+import io.micronaut.data.model.query.builder.sql.Dialect;
+import io.micronaut.data.repository.CrudRepository;
+
+import java.util.List;
+import java.util.Optional;
+
+@JdbcRepository(dialect = Dialect.H2)
+@Join(value = "books", type = Join.Type.LEFT_FETCH)
+public interface AuthorRepository extends CrudRepository<Author, Long> {
+
+    Optional<Author> queryByName(String name);
+
+    List<Author> queryByNameContains(String partialName);
+
+    Optional<Author> findByNameContains(String partialName); //findByNameContainsIgnoreCase has the same issue
+
+    //Note: findFirstByNameContains returns only the first row and therefore only one book.
+
+    /*
+     SELECT author_.`id`,
+            author_.`name`,
+            author_books_.`id` AS books_id,
+            author_books_.`title` AS books_title,
+            author_books_.`author` AS books_author
+     FROM (
+       SELECT id,name FROM author
+       WHERE (`name` LIKE CONCAT('%',:partialName,'%'))
+       LIMIT 1) author_
+     LEFT JOIN book author_books_ ON author_.id=author_books_.author;
+    */
+    @Query("SELECT author_.`id`,author_.`name`,author_books_.`id` AS books_id,author_books_.`title` AS books_title,author_books_.`author` AS books_author FROM (SELECT id,name FROM ji_author WHERE (`name` LIKE CONCAT('%',:partialName,'%')) LIMIT 1) author_ LEFT JOIN ji_book author_books_ ON author_.id=author_books_.author;")
+    Optional<Author> getOneByNameContains(String partialName);
+
+}

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/AuthorTest.groovy

@@ -0,0 +1,72 @@
+package io.micronaut.data.jdbc.h2.joinissue
+
+import io.micronaut.data.jdbc.h2.H2DBProperties
+import io.micronaut.test.extensions.spock.annotation.MicronautTest
+import jakarta.inject.Inject
+import spock.lang.Specification
+
+@MicronautTest
+@H2DBProperties
+class AuthorTest extends Specification {
+
+    @Inject
+    AuthorRepository authorRepository
+
+    void test() {
+        given:
+            var authorList = List.of(
+                    new Author(null, "Joe Doe",
+                            Set.of(new Book(null, "History of nothing"))),
+                    new Author(null, "Jane Doe",
+                            Set.of(new Book(null, "History of everything"),
+                                    new Book(null, "Doing awesome things"))))
+
+            authorRepository.saveAll(authorList)
+
+        when:
+            Author author = authorRepository.queryByName("Joe Doe").orElse(null)
+        then:
+            author.name() == "Joe Doe"
+            author.books().size() == 1
+
+        when:
+            List<Author> list = authorRepository.queryByNameContains("Doe")
+        then:
+            list.size() == 2
+            list.get(0).name() == "Joe Doe"
+            list.get(0).books().size() == 1
+            list.get(1).name() == "Jane Doe"
+            list.get(1).books().size() == 2
+
+        when:
+            author = authorRepository.getOneByNameContains("Doe").orElse(null)
+        then:
+            author.name() == "Joe Doe"
+            author.books().size() == 1
+
+        when:
+            author = authorRepository.getOneByNameContains("ne Doe").orElse(null)
+        then:
+            author.name() == "Jane Doe"
+            author.books().size() == 2
+
+        when:
+            author = this.authorRepository.findByNameContains("Doe").orElse(null)
+        then:
+            author.name() == "Joe Doe"
+            author.books().size() == 1
+
+        when:
+            author = this.authorRepository.findByNameContains("e Doe").orElse(null)
+        then:
+            author.name() == "Joe Doe"
+            author.books().size() == 1
+
+        when:
+            author = this.authorRepository.findByNameContains("ne Doe").orElse(null)
+        then:
+            author.name() == "Jane Doe"
+            author.books().size() == 2
+    }
+
+}

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/Book.java

@@ -0,0 +1,24 @@
+package io.micronaut.data.jdbc.h2.joinissue;
+
+import io.micronaut.core.annotation.Nullable;
+import io.micronaut.data.annotation.GeneratedValue;
+import io.micronaut.data.annotation.Id;
+import io.micronaut.data.annotation.MappedEntity;
+import io.micronaut.data.annotation.MappedProperty;
+import io.micronaut.data.annotation.Relation;
+
+@MappedEntity("ji_book")
+public record Book(
+        @Id
+        @GeneratedValue
+        Long id,
+        String title,
+        @Nullable
+        @Relation(value = Relation.Kind.MANY_TO_ONE)
+        @MappedProperty("author")
+        Author author) {
+    public Book(Long id, String title) {
+        this(id, title, null);
+    }
+}
+

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/Director.java

@@ -0,0 +1,62 @@
+package io.micronaut.data.jdbc.h2.joinissue;
+
+import io.micronaut.core.annotation.Nullable;
+import io.micronaut.data.annotation.GeneratedValue;
+import io.micronaut.data.annotation.Id;
+import io.micronaut.data.annotation.MappedEntity;
+import io.micronaut.data.annotation.Relation;
+
+import java.util.Set;
+
+@MappedEntity("ji_director")
+public class Director {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String name;
+
+    @Relation(value = Relation.Kind.ONE_TO_MANY, cascade = Relation.Cascade.ALL, mappedBy = "director")
+    Set<Movie> movies;
+
+    public Director(String name, @Nullable Set<Movie> movies) {
+        this.name = name;
+        this.movies = movies;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Set<Movie> getMovies() {
+        return movies;
+    }
+
+    public void setMovies(Set<Movie> movies) {
+        this.movies = movies;
+    }
+
+}
+
+//    @Override
+//    public String toString() {
+//        return "Director{" +
+//                "id=" + id +
+//                ", name='" + name + '\'' +
+//                ", movies=" + movies +
+//                '}';
+//    }
+//}

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/DirectorRepository.java

@@ -0,0 +1,23 @@
+package io.micronaut.data.jdbc.h2.joinissue;
+
+import io.micronaut.data.annotation.Join;
+import io.micronaut.data.jdbc.annotation.JdbcRepository;
+import io.micronaut.data.model.query.builder.sql.Dialect;
+import io.micronaut.data.repository.CrudRepository;
+
+import java.util.List;
+import java.util.Optional;
+
+@JdbcRepository(dialect = Dialect.H2)
+public interface DirectorRepository extends CrudRepository<Director, Long> {
+
+    @Join(value = "movies", type= Join.Type.LEFT_FETCH)
+    Optional<Director> queryByName(String name);
+
+    @Join(value = "movies", type = Join.Type.LEFT_FETCH)
+    Optional<Director> findByNameContains(String partialName);
+
+    @Join(value = "movies", type = Join.Type.LEFT_FETCH)
+    List<Director> queryByNameContains(String partialName);
+
+}

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/DirectorSpec.groovy

@@ -0,0 +1,48 @@
+package io.micronaut.data.jdbc.h2.joinissue
+
+import io.micronaut.data.jdbc.h2.H2DBProperties
+import io.micronaut.test.extensions.spock.annotation.MicronautTest
+import jakarta.inject.Inject
+import spock.lang.Specification
+
+@MicronautTest
+@H2DBProperties
+class DirectorSpec extends Specification {
+
+    @Inject
+    DirectorRepository directorRepository
+
+    def 'test'() {
+        given:
+            var directorList = List.of(
+                    new Director("John Jones",
+                            Set.of(new Movie("Random Movie"))),
+                    new Director("Ann Jones",
+                            Set.of(new Movie("Super Hero Movie"),
+                                    new Movie("Anther Movie with Heroes"))))
+
+            directorRepository.saveAll(directorList)
+
+        when:
+            var director = directorRepository.queryByName("John Jones").orElse(null)
+        then:
+            director.getName() == "John Jones"
+            director.getMovies().size() == 1
+
+        when:
+            var list = directorRepository.queryByNameContains("n Jones")
+        then:
+            list.size() == 2
+            list.get(0).getName() == "John Jones"
+            list.get(0).getMovies().size() == 1
+            list.get(1).getName() == "Ann Jones"
+            list.get(1).getMovies().size() == 2
+
+        when:
+            director = directorRepository.findByNameContains("n Jones").orElse(null)
+        then:
+            director.getName() == "John Jones"
+            director.getMovies().size() == 1
+
+    }
+}

data-jdbc/src/test/groovy/io/micronaut/data/jdbc/h2/joinissue/Movie.java

@@ -0,0 +1,60 @@
+package io.micronaut.data.jdbc.h2.joinissue;
+
+import io.micronaut.core.annotation.Nullable;
+import io.micronaut.data.annotation.GeneratedValue;
+import io.micronaut.data.annotation.Id;
+import io.micronaut.data.annotation.MappedEntity;
+import io.micronaut.data.annotation.MappedProperty;
+import io.micronaut.data.annotation.Relation;
+
+@MappedEntity("ji_movie")
+public class Movie {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String title;
+
+    @Nullable
+    @Relation(Relation.Kind.MANY_TO_ONE)
+    @MappedProperty("director")
+    private Director director;
+
+    public Movie(String title) {
+        this.title = title;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public Director getDirector() {
+        return director;
+    }
+
+    public void setDirector(Director director) {
+        this.director = director;
+    }
+
+    @Override
+    public String toString() {
+        return "Movie{" +
+                "id=" + id +
+                ", title='" + title + '\'' +
+                ", director=" + director +
+                '}';
+    }
+}

data-runtime/src/main/java/io/micronaut/data/runtime/mapper/sql/SqlResultEntityTypeMapper.java

@@ -263,15 +263,23 @@ public PushingMapper<RS, R> readOneMapper() {
             return new PushingMapper<>() {
 
                 final MappingContext<R> ctx = MappingContext.of(entity, startingPrefix);
+                Object entityId;
                 R entityInstance;
 
                 @Override
                 public void processRow(RS row) {
-                    if (entityInstance == null) {
+                    Object id = readEntityId(row, ctx);
+                    if (id == null) {
+                        throw new IllegalStateException("Entity needs to have an ID when JOINs are used!");
+                    }
+                    if (entityId == null) {
+                        entityId = id;
                         entityInstance = readEntity(row, ctx, null, null);
-                    } else {
-                        readChildren(row, entityInstance, null, ctx);
+                    } else if (entityId != id) {
+                        // We want only one entity, every thing else should be skipped
+                        return;
                     }
+                    readChildren(row, entityInstance, null, ctx);
                 }
 
                 @Override