Support the distinct keyword

Author: nakamura-to

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/DistinctOption.java

@@ -0,0 +1,6 @@
+package org.seasar.doma.jdbc.criteria;
+
+public enum DistinctOption {
+  ENABLED,
+  DISABLED
+}

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/context/SelectContext.java

@@ -10,13 +10,14 @@
 import java.util.function.BiConsumer;
 import java.util.stream.Stream;
 import org.seasar.doma.internal.util.Pair;
+import org.seasar.doma.jdbc.criteria.DistinctOption;
 import org.seasar.doma.jdbc.criteria.def.EntityDef;
 import org.seasar.doma.jdbc.criteria.def.PropertyDef;
 
 public class SelectContext implements Context {
   public final EntityDef<?> entityDef;
   public Projection projection;
-  public boolean distinct;
+  public DistinctOption distinct = DistinctOption.DISABLED;
   public final List<Join> joins = new ArrayList<>();
   public List<Criterion> where = new ArrayList<>();
   public final List<PropertyDef<?>> groupBy = new ArrayList<>();

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/declaration/SelectFromDeclaration.java

@@ -7,6 +7,7 @@
 import org.seasar.doma.DomaException;
 import org.seasar.doma.internal.util.Pair;
 import org.seasar.doma.jdbc.criteria.AssociationKind;
+import org.seasar.doma.jdbc.criteria.DistinctOption;
 import org.seasar.doma.jdbc.criteria.ForUpdateOption;
 import org.seasar.doma.jdbc.criteria.context.ForUpdate;
 import org.seasar.doma.jdbc.criteria.context.Join;
@@ -30,6 +31,10 @@ public SelectContext getContext() {
     return context;
   }
 
+  public void distinct(DistinctOption distinctOption) {
+    context.distinct = distinctOption;
+  }
+
   public void innerJoin(EntityDef<?> entityDef, Consumer<JoinDeclaration> block) {
     Objects.requireNonNull(entityDef);
     Objects.requireNonNull(block);

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/query/SelectBuilder.java

@@ -11,6 +11,7 @@
 import org.seasar.doma.jdbc.PreparedSql;
 import org.seasar.doma.jdbc.SqlKind;
 import org.seasar.doma.jdbc.SqlLogType;
+import org.seasar.doma.jdbc.criteria.DistinctOption;
 import org.seasar.doma.jdbc.criteria.ForUpdateOption;
 import org.seasar.doma.jdbc.criteria.context.Criterion;
 import org.seasar.doma.jdbc.criteria.context.Join;
@@ -77,7 +78,7 @@ void interpret() {
   private void select() {
     buf.appendSql("select ");
 
-    if (context.distinct) {
+    if (context.distinct == DistinctOption.ENABLED) {
       buf.appendSql("distinct ");
     }
 

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/statement/EntityqlSelectStatement.java

@@ -8,6 +8,7 @@
 import org.seasar.doma.jdbc.PreparedSql;
 import org.seasar.doma.jdbc.command.Command;
 import org.seasar.doma.jdbc.criteria.AssociationKind;
+import org.seasar.doma.jdbc.criteria.DistinctOption;
 import org.seasar.doma.jdbc.criteria.ForUpdateOption;
 import org.seasar.doma.jdbc.criteria.command.AssociateCommand;
 import org.seasar.doma.jdbc.criteria.context.SelectContext;
@@ -31,6 +32,16 @@ public EntityqlSelectStatement(Config config, SelectFromDeclaration declaration)
     this.declaration = Objects.requireNonNull(declaration);
   }
 
+  public EntityqlSelectStatement<ENTITY> distinct() {
+    declaration.distinct(DistinctOption.ENABLED);
+    return this;
+  }
+
+  public EntityqlSelectStatement<ENTITY> distinct(DistinctOption distinctOption) {
+    declaration.distinct(distinctOption);
+    return this;
+  }
+
   public EntityqlSelectStatement<ENTITY> innerJoin(
       EntityDef<?> entityDef, Consumer<JoinDeclaration> block) {
     declaration.innerJoin(entityDef, block);

doma-core/src/main/java/org/seasar/doma/jdbc/criteria/statement/NativeSqlSelectStarting.java

@@ -12,6 +12,7 @@
 import org.seasar.doma.jdbc.Config;
 import org.seasar.doma.jdbc.ObjectProvider;
 import org.seasar.doma.jdbc.command.Command;
+import org.seasar.doma.jdbc.criteria.DistinctOption;
 import org.seasar.doma.jdbc.criteria.ForUpdateOption;
 import org.seasar.doma.jdbc.criteria.command.MappedResultProvider;
 import org.seasar.doma.jdbc.criteria.context.SelectContext;
@@ -49,6 +50,16 @@ public NativeSqlSelectStarting(
     this.entityDef = Objects.requireNonNull(entityDef);
   }
 
+  public NativeSqlSelectStarting<ENTITY> distinct() {
+    declaration.distinct(DistinctOption.ENABLED);
+    return this;
+  }
+
+  public NativeSqlSelectStarting<ENTITY> distinct(DistinctOption distinctOption) {
+    declaration.distinct(distinctOption);
+    return this;
+  }
+
   public NativeSqlSelectStarting<ENTITY> innerJoin(
       EntityDef<?> entityDef, Consumer<JoinDeclaration> block) {
     Objects.requireNonNull(entityDef);

doma-core/src/test/java/org/seasar/doma/jdbc/criteria/EntityqlSelectTest.java

@@ -193,4 +193,36 @@ void offset_null() {
     assertEquals(
         "select t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_", sql.getFormattedSql());
   }
+
+  @Test
+  void distinct() {
+    Emp_ e = new Emp_();
+    Statement<List<Emp>> stmt = entityql.from(e).distinct();
+
+    Sql<?> sql = stmt.asSql();
+    assertEquals(
+        "select distinct t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_",
+        sql.getFormattedSql());
+  }
+
+  @Test
+  void distinct_enabled() {
+    Emp_ e = new Emp_();
+    Statement<List<Emp>> stmt = entityql.from(e).distinct(DistinctOption.ENABLED);
+
+    Sql<?> sql = stmt.asSql();
+    assertEquals(
+        "select distinct t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_",
+        sql.getFormattedSql());
+  }
+
+  @Test
+  void distinct_disabled() {
+    Emp_ e = new Emp_();
+    Statement<List<Emp>> stmt = entityql.from(e).distinct(DistinctOption.DISABLED);
+
+    Sql<?> sql = stmt.asSql();
+    assertEquals(
+        "select t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_", sql.getFormattedSql());
+  }
 }

doma-core/src/test/java/org/seasar/doma/jdbc/criteria/NativeSqlSelectTest.java

@@ -892,4 +892,36 @@ void peek() {
             .union(nativeSql.from(d).select(d.name).peek(System.out::println))
             .peek(System.out::println);
   }
+
+  @Test
+  void distinct() {
+    Emp_ e = new Emp_();
+    Buildable<?> stmt = nativeSql.from(e).distinct().where(c -> c.eq(e.name, "a"));
+    Sql<?> sql = stmt.asSql();
+    assertEquals(
+        "select distinct t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_ where t0_.NAME = 'a'",
+        sql.getFormattedSql());
+  }
+
+  @Test
+  void distinct_enabled() {
+    Emp_ e = new Emp_();
+    Buildable<?> stmt =
+        nativeSql.from(e).distinct(DistinctOption.ENABLED).where(c -> c.eq(e.name, "a"));
+    Sql<?> sql = stmt.asSql();
+    assertEquals(
+        "select distinct t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_ where t0_.NAME = 'a'",
+        sql.getFormattedSql());
+  }
+
+  @Test
+  void distinct_disabled() {
+    Emp_ e = new Emp_();
+    Buildable<?> stmt =
+        nativeSql.from(e).distinct(DistinctOption.DISABLED).where(c -> c.eq(e.name, "a"));
+    Sql<?> sql = stmt.asSql();
+    assertEquals(
+        "select t0_.ID, t0_.NAME, t0_.SALARY, t0_.VERSION from EMP t0_ where t0_.NAME = 'a'",
+        sql.getFormattedSql());
+  }
 }