chore(java-engine): fix counting view issue (#1144)

Thanks

Author: goldmedal

wren-core-legacy/wren-base/src/main/java/io/wren/base/sqlrewrite/analyzer/StatementAnalyzer.java

@@ -403,22 +403,22 @@ private void analyzeSelectSingleColumn(SingleColumn singleColumn, Scope scope, I
             ExpressionAnalysis expressionAnalysis = analyzeExpression(singleColumn.getExpression(), scope);
 
             if (expressionAnalysis.isRequireRelation()) {
-                Node source = scope.getRelationId().getSourceNode()
-                        .orElseThrow(() -> new IllegalArgumentException("count(*) should have a followed source"));
-
-                // collect only the source node that is a table for generating the required column for models
-                DefaultTraversalVisitor<Scope> visitor = new DefaultTraversalVisitor<>()
-                {
-                    @Override
-                    protected Void visitTable(Table node, Scope scope)
+                Optional<Node> source = scope.getRelationId().getSourceNode();
+                if (source.isPresent()) {
+                    // collect only the source node that is a table for generating the required column for models
+                    DefaultTraversalVisitor<Scope> visitor = new DefaultTraversalVisitor<>()
                     {
-                        if (scope.getNamedQuery(node.getName().getSuffix()).isEmpty()) {
-                            analysis.addRequiredSourceNode(node);
+                        @Override
+                        protected Void visitTable(Table node, Scope scope)
+                        {
+                            if (scope.getNamedQuery(node.getName().getSuffix()).isEmpty()) {
+                                analysis.addRequiredSourceNode(node);
+                            }
+                            return null;
                         }
-                        return null;
-                    }
-                };
-                visitor.process(source, scope);
+                    };
+                    visitor.process(source.get(), scope);
+                }
             }
         }
 

wren-core-legacy/wren-tests/src/test/java/io/wren/testing/TestMDLResourceV2.java

@@ -18,6 +18,7 @@
 import io.airlift.json.JsonCodec;
 import io.wren.base.dto.JoinType;
 import io.wren.base.dto.Manifest;
+import io.wren.base.dto.View;
 import io.wren.main.web.dto.DryPlanDtoV2;
 import org.testng.annotations.Test;
 
@@ -309,6 +310,58 @@ orders_custkey AS (
                 """);
     }
 
+    @Test
+    public void testCountView()
+    {
+        Manifest manifest = Manifest.builder()
+                .setCatalog("wrenai")
+                .setSchema("tpch")
+                .setModels(List.of(
+                        model("Customer", "SELECT * FROM tpch.customer",
+                                List.of(column("custkey", "integer", null, false, "c_custkey"),
+                                        column("name", "varchar", null, false, "c_name")))))
+                .setViews(List.of(new View("view1", "select * from Customer", ImmutableMap.of())))
+                .build();
+        String manifestStr = base64Encode(toJson(manifest));
+        DryPlanDtoV2 dryPlanDto = new DryPlanDtoV2(manifestStr, "select count(*) from view1");
+        String dryPlan = dryPlanV2(dryPlanDto);
+        assertThat(dryPlan).isEqualTo("""
+                "WITH
+                  "Customer" AS (
+                   SELECT
+                     "Customer"."custkey" "custkey"
+                   , "Customer"."name" "name"
+                   FROM
+                     (
+                      SELECT
+                        "Customer"."custkey" "custkey"
+                      , "Customer"."name" "name"
+                      FROM
+                        (
+                         SELECT
+                           c_custkey "custkey"
+                         , c_name "name"
+                         FROM
+                           (
+                            SELECT *
+                            FROM
+                              tpch.customer
+                         )  "Customer"
+                      )  "Customer"
+                   )  "Customer"
+                )\s
+                , "view1" AS (
+                   SELECT *
+                   FROM
+                     Customer
+                )\s
+                SELECT count(*)
+                FROM
+                  view1
+                "
+                """);
+    }
+
     private String toJson(Manifest manifest)
     {
         return MANIFEST_JSON_CODEC.toJson(manifest);