Insert the TOP clause in the correct position (#1077)

nakamura-to · web-flow · commit ec6e3f3ec94e · 2024-03-09T09:12:26.000+09:00
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/dialect/Mssql2008PagingTransformer.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/dialect/Mssql2008PagingTransformer.java
@@ -1,10 +1,14 @@
 package org.seasar.doma.internal.jdbc.dialect;
 
+import java.util.Optional;
+import org.seasar.doma.internal.jdbc.sql.SimpleSqlNodeVisitor;
 import org.seasar.doma.internal.jdbc.sql.node.AnonymousNode;
+import org.seasar.doma.internal.jdbc.sql.node.DistinctNode;
 import org.seasar.doma.internal.jdbc.sql.node.FragmentNode;
 import org.seasar.doma.internal.jdbc.sql.node.SelectClauseNode;
 import org.seasar.doma.internal.jdbc.sql.node.SelectStatementNode;
 import org.seasar.doma.jdbc.SqlNode;
+import org.seasar.doma.jdbc.SqlNodeVisitor;
 
 public class Mssql2008PagingTransformer extends StandardPagingTransformer {
 
@@ -36,11 +40,29 @@ public SqlNode visitSelectStatementNode(SelectStatementNode node, Void p) {
 
   protected SqlNode appendTopNode(SelectStatementNode node) {
     SelectClauseNode select = new SelectClauseNode(node.getSelectClauseNode().getWordNode());
-    select.appendNode(new FragmentNode(" top (" + limit + ")"));
-    for (SqlNode child : node.getSelectClauseNode().getChildren()) {
-      select.appendNode(child);
+    FragmentNode top = new FragmentNode(" top (" + limit + ")");
+    Optional<SqlNode> optionalDistinctNode = getDistinctNode(node.getSelectClauseNode());
+
+    if (optionalDistinctNode.isPresent()) {
+      SqlNode distinctNode = optionalDistinctNode.get();
+      for (SqlNode child : node.getSelectClauseNode().getChildren()) {
+        select.appendNode(child);
+        if (child == distinctNode) {
+          select.appendNode(top);
+        }
+      }
+    } else {
+      select.appendNode(top);
+      for (SqlNode child : node.getSelectClauseNode().getChildren()) {
+        select.appendNode(child);
+      }
     }
 
+    return createSelectStatementNode(node, select);
+  }
+
+  private static SelectStatementNode createSelectStatementNode(
+      SelectStatementNode node, SelectClauseNode select) {
     SelectStatementNode result = new SelectStatementNode();
     result.setSelectClauseNode(select);
     result.setFromClauseNode(node.getFromClauseNode());
@@ -52,4 +74,22 @@ protected SqlNode appendTopNode(SelectStatementNode node) {
     result.setOptionClauseNode(node.getOptionClauseNode());
     return result;
   }
+
+  private Optional<SqlNode> getDistinctNode(SelectClauseNode node) {
+    SqlNodeVisitor<Boolean, Void> visitor =
+        new SimpleSqlNodeVisitor<Boolean, Void>() {
+
+          @Override
+          protected Boolean defaultAction(SqlNode node, Void o) {
+            return false;
+          }
+
+          @Override
+          public Boolean visitDistinctNode(DistinctNode node, Void o) {
+            return true;
+          }
+        };
+
+    return node.getChildren().stream().filter(child -> child.accept(visitor, null)).findFirst();
+  }
 }
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/NodePreparedSqlBuilder.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/NodePreparedSqlBuilder.java
@@ -26,6 +26,7 @@
 import org.seasar.doma.internal.jdbc.sql.node.AnonymousNode;
 import org.seasar.doma.internal.jdbc.sql.node.BindVariableNode;
 import org.seasar.doma.internal.jdbc.sql.node.CommentNode;
+import org.seasar.doma.internal.jdbc.sql.node.DistinctNode;
 import org.seasar.doma.internal.jdbc.sql.node.ElseNode;
 import org.seasar.doma.internal.jdbc.sql.node.ElseifNode;
 import org.seasar.doma.internal.jdbc.sql.node.EmbeddedVariableNode;
@@ -688,6 +689,12 @@ public Void visitWordNode(WordNode node, Context p) {
     return null;
   }
 
+  @Override
+  public Void visitDistinctNode(DistinctNode node, Context context) {
+    WordNode wordNode = node.getWordNode();
+    return wordNode.accept(this, context);
+  }
+
   @Override
   public Void visitFragmentNode(FragmentNode node, Context p) {
     p.setAvailable(true);
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SimpleSqlNodeVisitor.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SimpleSqlNodeVisitor.java
@@ -3,6 +3,7 @@
 import org.seasar.doma.internal.jdbc.sql.node.AnonymousNode;
 import org.seasar.doma.internal.jdbc.sql.node.BindVariableNode;
 import org.seasar.doma.internal.jdbc.sql.node.CommentNode;
+import org.seasar.doma.internal.jdbc.sql.node.DistinctNode;
 import org.seasar.doma.internal.jdbc.sql.node.ElseNode;
 import org.seasar.doma.internal.jdbc.sql.node.ElseifNode;
 import org.seasar.doma.internal.jdbc.sql.node.EmbeddedVariableNode;
@@ -57,6 +58,11 @@ public R visitCommentNode(CommentNode node, P p) {
     return defaultAction(node, p);
   }
 
+  @Override
+  public R visitDistinctNode(DistinctNode node, P p) {
+    return defaultAction(node, p);
+  }
+
   @Override
   public R visitElseifNode(ElseifNode node, P p) {
     return defaultAction(node, p);
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SqlParser.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SqlParser.java
@@ -12,6 +12,7 @@
 import org.seasar.doma.internal.jdbc.sql.node.BindVariableNode;
 import org.seasar.doma.internal.jdbc.sql.node.BlockNode;
 import org.seasar.doma.internal.jdbc.sql.node.CommentNode;
+import org.seasar.doma.internal.jdbc.sql.node.DistinctNode;
 import org.seasar.doma.internal.jdbc.sql.node.ElseNode;
 import org.seasar.doma.internal.jdbc.sql.node.ElseifNode;
 import org.seasar.doma.internal.jdbc.sql.node.EmbeddedVariableNode;
@@ -131,6 +132,11 @@ public SqlNode parse() {
             parseOptionWord();
             break;
           }
+        case DISTINCT_WORD:
+          {
+            parseDistinctWord();
+            break;
+          }
         case UPDATE_WORD:
           {
             parseUpdateWord();
@@ -400,6 +406,11 @@ protected void parseWord() {
     appendNode(node);
   }
 
+  protected void parseDistinctWord() {
+    DistinctNode node = new DistinctNode(token);
+    appendNode(node);
+  }
+
   protected void parseComment() {
     CommentNode node = new CommentNode(token);
     appendNode(node);
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SqlTokenType.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SqlTokenType.java
@@ -141,6 +141,8 @@ public String extract(String token) {
 
   WORD,
 
+  DISTINCT_WORD,
+
   OTHER,
 
   WHITESPACE,
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SqlTokenizer.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/SqlTokenizer.java
@@ -5,6 +5,7 @@
 import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.BLOCK_COMMENT;
 import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.CLOSED_PARENS;
 import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.DELIMITER;
+import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.DISTINCT_WORD;
 import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.ELSEIF_BLOCK_COMMENT;
 import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.ELSE_BLOCK_COMMENT;
 import static org.seasar.doma.internal.jdbc.sql.SqlTokenType.EMBEDDED_VARIABLE_BLOCK_COMMENT;
@@ -243,6 +244,18 @@ protected void peekEightChars(
       type = OPTION_WORD;
       buf.position(buf.position() - 2);
       return;
+    } else if ((c == 'd' || c == 'D')
+        && (c2 == 'i' || c2 == 'I')
+        && (c3 == 's' || c3 == 'S')
+        && (c4 == 't' || c4 == 'T')
+        && (c5 == 'i' || c5 == 'I')
+        && (c6 == 'n' || c6 == 'N')
+        && (c7 == 'c' || c7 == 'C')
+        && (c8 == 't' || c8 == 'T')) {
+      type = DISTINCT_WORD;
+      if (isWordTerminated()) {
+        return;
+      }
     }
     buf.position(buf.position() - 1);
     peekSevenChars(c, c2, c3, c4, c5, c6, c7);
diff --git a/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/node/DistinctNode.java b/doma-core/src/main/java/org/seasar/doma/internal/jdbc/sql/node/DistinctNode.java
@@ -0,0 +1,32 @@
+package org.seasar.doma.internal.jdbc.sql.node;
+
+import org.seasar.doma.DomaNullPointerException;
+import org.seasar.doma.jdbc.JdbcUnsupportedOperationException;
+import org.seasar.doma.jdbc.SqlNode;
+import org.seasar.doma.jdbc.SqlNodeVisitor;
+
+public class DistinctNode extends AbstractSqlNode {
+
+  protected final WordNode wordNode;
+
+  public DistinctNode(String word) {
+    wordNode = new WordNode(word, false);
+  }
+
+  public WordNode getWordNode() {
+    return wordNode;
+  }
+
+  @Override
+  public void appendNode(SqlNode child) {
+    throw new JdbcUnsupportedOperationException(getClass().getName(), "addNode");
+  }
+
+  @Override
+  public <R, P> R accept(SqlNodeVisitor<R, P> visitor, P p) {
+    if (visitor == null) {
+      throw new DomaNullPointerException("visitor");
+    }
+    return visitor.visitDistinctNode(this, p);
+  }
+}
diff --git a/doma-core/src/main/java/org/seasar/doma/jdbc/SqlNodeVisitor.java b/doma-core/src/main/java/org/seasar/doma/jdbc/SqlNodeVisitor.java
@@ -18,6 +18,8 @@ public interface SqlNodeVisitor<R, P> {
 
   R visitCommentNode(CommentNode node, P p);
 
+  R visitDistinctNode(DistinctNode node, P p);
+
   R visitElseifNode(ElseifNode node, P p);
 
   R visitElseNode(ElseNode node, P p);
diff --git a/doma-core/src/test/java/org/seasar/doma/internal/jdbc/dialect/Mssql2008PagingTransformerTest.java b/doma-core/src/test/java/org/seasar/doma/internal/jdbc/dialect/Mssql2008PagingTransformerTest.java
@@ -50,4 +50,28 @@ public void testLimitOnly() {
     PreparedSql sql = sqlBuilder.build(sqlNode, Function.identity());
     assertEquals(expected, sql.getRawSql());
   }
+
+  @Test
+  public void testLimitOnly_distinct() {
+    String expected = "select distinct top (10) emp.id from emp order by emp.id";
+    Mssql2008PagingTransformer transformer = new Mssql2008PagingTransformer(-1, 10);
+    SqlParser parser = new SqlParser("select distinct emp.id from emp order by emp.id");
+    SqlNode sqlNode = transformer.transform(parser.parse());
+    NodePreparedSqlBuilder sqlBuilder =
+        new NodePreparedSqlBuilder(new MockConfig(), SqlKind.SELECT, "dummyPath");
+    PreparedSql sql = sqlBuilder.build(sqlNode, Function.identity());
+    assertEquals(expected, sql.getRawSql());
+  }
+
+  @Test
+  public void testLimitOnly_countDistinct() {
+    String expected = "select top (10) count(distinct emp.id) from emp order by emp.id";
+    Mssql2008PagingTransformer transformer = new Mssql2008PagingTransformer(-1, 10);
+    SqlParser parser = new SqlParser("select count(distinct emp.id) from emp order by emp.id");
+    SqlNode sqlNode = transformer.transform(parser.parse());
+    NodePreparedSqlBuilder sqlBuilder =
+        new NodePreparedSqlBuilder(new MockConfig(), SqlKind.SELECT, "dummyPath");
+    PreparedSql sql = sqlBuilder.build(sqlNode, Function.identity());
+    assertEquals(expected, sql.getRawSql());
+  }
 }
diff --git a/integration-test-java/src/main/java/org/seasar/doma/it/dao/EmployeeDao.java b/integration-test-java/src/main/java/org/seasar/doma/it/dao/EmployeeDao.java
@@ -69,6 +69,9 @@ public interface EmployeeDao {
   @Select
   List<Employee> selectAll(SelectOptions options);
 
+  @Select
+  List<Employee> selectDistinctAll(SelectOptions options);
+
   @Select(ensureResultMapping = true)
   List<Employee> selectOnlyNameWithMappingCheck();
 
diff --git a/integration-test-java/src/main/resources/META-INF/org/seasar/doma/it/dao/EmployeeDao/selectDistinctAll.sql b/integration-test-java/src/main/resources/META-INF/org/seasar/doma/it/dao/EmployeeDao/selectDistinctAll.sql
@@ -0,0 +1 @@
+select distinct * from EMPLOYEE order by EMPLOYEE_ID
diff --git a/integration-test-java/src/test/java/org/seasar/doma/it/sqlfile/SqlFileSelectPagingTest.java b/integration-test-java/src/test/java/org/seasar/doma/it/sqlfile/SqlFileSelectPagingTest.java
@@ -69,6 +69,18 @@ public void testLimitOnly(Config config) throws Exception {
     assertEquals(Integer.valueOf(5), employees.get(4).getEmployeeId());
   }
 
+  @Test
+  public void testLimitOnly_distinct(Config config) throws Exception {
+    EmployeeDao dao = new EmployeeDaoImpl(config);
+    List<Employee> employees = dao.selectDistinctAll(SelectOptions.get().limit(5));
+    assertEquals(5, employees.size());
+    assertEquals(Integer.valueOf(1), employees.get(0).getEmployeeId());
+    assertEquals(Integer.valueOf(2), employees.get(1).getEmployeeId());
+    assertEquals(Integer.valueOf(3), employees.get(2).getEmployeeId());
+    assertEquals(Integer.valueOf(4), employees.get(3).getEmployeeId());
+    assertEquals(Integer.valueOf(5), employees.get(4).getEmployeeId());
+  }
+
   @Test
   public void testOffsetOnly(Config config) throws Exception {
     EmployeeDao dao = new EmployeeDaoImpl(config);
