fix: fixed github issues 288, close #288

mybatis-flex-core/src/main/java/com/mybatisflex/core/query/DistinctQueryColumn.java

@@ -15,14 +15,17 @@
  */
 package com.mybatisflex.core.query;
 
+import com.mybatisflex.core.FlexConsts;
 import com.mybatisflex.core.constant.SqlConsts;
 import com.mybatisflex.core.dialect.IDialect;
 import com.mybatisflex.core.util.CollectionUtil;
 import com.mybatisflex.core.util.StringUtil;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 
-public class DistinctQueryColumn extends QueryColumn {
+public class DistinctQueryColumn extends QueryColumn implements HasParamsColumn {
 
     private List<QueryColumn> queryColumns;
 
@@ -62,4 +65,21 @@ public class DistinctQueryColumn extends QueryColumn {
         return clone;
     }
 
+    @Override
+    public Object[] getParamValues() {
+        if (CollectionUtil.isEmpty(queryColumns)) {
+            return FlexConsts.EMPTY_ARRAY;
+        }
+
+        List<Object> params = new ArrayList<>();
+
+        for (QueryColumn queryColumn : queryColumns) {
+            if (queryColumn instanceof HasParamsColumn) {
+                Object[] paramValues = ((HasParamsColumn) queryColumn).getParamValues();
+                params.addAll(Arrays.asList(paramValues));
+            }
+        }
+
+        return params.toArray();
+    }
 }

mybatis-flex-core/src/test/java/com/mybatisflex/coretest/QueryWrapperTest.java

@@ -0,0 +1,70 @@
+/*
+ *  Copyright (c) 2022-2023, Mybatis-Flex (fuhai999@gmail.com).
+ *  <p>
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *  <p>
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *  <p>
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package com.mybatisflex.coretest;
+
+import com.github.vertical_blank.sqlformatter.SqlFormatter;
+import com.mybatisflex.core.query.CPI;
+import com.mybatisflex.core.query.QueryColumn;
+import com.mybatisflex.core.query.QueryWrapper;
+import org.junit.Assert;
+import org.junit.Test;
+
+import static com.mybatisflex.core.query.QueryMethods.*;
+import static com.mybatisflex.coretest.table.AccountTableDef.ACCOUNT;
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Lambda 构建 SQL 测试。
+ *
+ * @author 王帅
+ * @since 2023-10-01
+ */
+public class QueryWrapperTest {
+
+    public static void printSQL(QueryWrapper queryWrapper) {
+        System.out.println(SqlFormatter.format(queryWrapper.toSQL()));
+    }
+
+
+    /**
+     * https://github.com/mybatis-flex/mybatis-flex/issues/288
+     */
+    @Test
+    public void testIssues288() {
+        final QueryWrapper query = QueryWrapper.create();
+        final QueryColumn storeColumn = column("temp", "store_id");
+        query.select(
+                count(distinct(case_()
+                    .when(string("purchasePerson").gt(1)).then(1)
+                    .else_(0).end())).as("repurchasePerson")
+            ).from(
+                select(ACCOUNT.ID,
+                    ACCOUNT.ID,
+                    sum(ACCOUNT.ID).as("purchasePerson")
+                ).from(ACCOUNT)
+                    .where(ACCOUNT.ID.in(5))
+                    .groupBy(ACCOUNT.ID,
+                        ACCOUNT.ID)).as("temp")
+            .groupBy(storeColumn);
+
+        Object[] valueArray = CPI.getValueArray(query);
+        Assert.assertEquals(valueArray.length, 2);
+        printSQL(query);
+    }
+
+
+}