Ignore non-field columns when collecting tree-view source names

integration-test/src/test/java/org/apache/iotdb/relational/it/schema/IoTDBTreeToTableViewAutoSyncIT.java

@@ -600,6 +600,32 @@ public void testAlterTemplateOnAncestorPathAddsColumns() throws Exception {
     }
   }
 
+  /**
+   * A TAG column name is not a source measurement. It must not prevent an explicit FROM column from
+   * referencing a tree measurement with the same name.
+   */
+  @Test
+  public void testTagColumnNameDoesNotBlockFromSource() throws Exception {
+    final String treeDb = "root.as21";
+    final String viewDb = "as21";
+    try (Connection tree = treeConnection();
+        Connection table = tableConnection()) {
+      execute(tree, "CREATE DATABASE " + treeDb);
+      execute(tree, "CREATE TIMESERIES " + treeDb + ".d1.s1 DOUBLE");
+
+      execute(table, "CREATE DATABASE " + viewDb);
+      execute(table, "USE " + viewDb);
+      execute(table, "CREATE VIEW v (dev STRING TAG, dev_s1 STRING TAG) AS " + treeDb + ".**");
+
+      // Create the measurement after the view so that it is not auto-detected as a column.
+      execute(tree, "CREATE TIMESERIES " + treeDb + ".d1.dev_s1 DOUBLE");
+
+      execute(table, "ALTER VIEW v ADD COLUMN test DOUBLE FIELD FROM dev_s1");
+
+      Assert.assertEquals("DOUBLE", fieldColumns(table, viewDb, "v").get("test"));
+    }
+  }
+
   // ==================== helpers ====================
 
   private static Connection treeConnection() throws SQLException {

iotdb-core/confignode/src/test/java/org/apache/iotdb/confignode/manager/ClusterSchemaManagerTest.java

@@ -23,9 +23,13 @@
 import org.apache.iotdb.commons.exception.table.ColumnInAlterException;
 import org.apache.iotdb.commons.exception.table.ColumnInDeletionException;
 import org.apache.iotdb.commons.exception.table.TableInDeletionException;
+import org.apache.iotdb.commons.path.PartialPath;
+import org.apache.iotdb.commons.schema.table.TableNodeStatus;
+import org.apache.iotdb.commons.schema.table.TreeViewSchema;
 import org.apache.iotdb.commons.schema.table.TsTable;
 import org.apache.iotdb.commons.schema.table.TsTableInternalRPCUtil;
 import org.apache.iotdb.commons.schema.table.column.FieldColumnSchema;
+import org.apache.iotdb.commons.schema.table.column.TagColumnSchema;
 import org.apache.iotdb.commons.schema.table.column.TsTableColumnSchema;
 import org.apache.iotdb.confignode.conf.ConfigNodeConfig;
 import org.apache.iotdb.confignode.conf.ConfigNodeDescriptor;
@@ -37,6 +41,7 @@
 import org.apache.iotdb.confignode.consensus.request.write.table.PreCreateTablePlan;
 import org.apache.iotdb.confignode.consensus.request.write.table.PreDeleteColumnPlan;
 import org.apache.iotdb.confignode.consensus.request.write.table.PreDeleteTablePlan;
+import org.apache.iotdb.confignode.consensus.request.write.table.view.PreCreateTableViewPlan;
 import org.apache.iotdb.confignode.manager.consensus.ConsensusManager;
 import org.apache.iotdb.confignode.manager.node.NodeManager;
 import org.apache.iotdb.confignode.manager.partition.PartitionManager;
@@ -373,6 +378,34 @@ private static FieldColumnSchema field(final String columnName) {
     return new FieldColumnSchema(columnName, TSDataType.INT32, TSEncoding.RLE, CompressionType.LZ4);
   }
 
+  @Test
+  public void testAddColumnIgnoresNonFieldColumnNamesAsSources() throws Exception {
+    final String database = "root.source_name_test";
+    final String viewName = "tree_view";
+    final ClusterSchemaInfo clusterSchemaInfo = new ClusterSchemaInfo();
+    clusterSchemaInfo.createDatabase(
+        new DatabaseSchemaPlan(
+            ConfigPhysicalPlanType.CreateDatabase,
+            new TDatabaseSchema(database).setIsTableModel(true)));
+    final TsTable view = new TsTable(viewName);
+    Assert.assertNull(TreeViewSchema.setPathPattern(view, new PartialPath("root.sg.**")));
+    view.addColumnSchema(new FieldColumnSchema("s1", TSDataType.INT32));
+    view.addColumnSchema(new TagColumnSchema("dev_s1", TSDataType.STRING));
+    clusterSchemaInfo.preCreateTableView(
+        new PreCreateTableViewPlan(database, view, TableNodeStatus.PRE_CREATE));
+    clusterSchemaInfo.commitCreateTable(new CommitCreateTablePlan(database, viewName));
+    final ClusterSchemaManager clusterSchemaManager = managerOf(clusterSchemaInfo);
+
+    // The TAG column dev_s1 is not a source measurement, so it must not block this FROM column.
+    final FieldColumnSchema test = new FieldColumnSchema("test", TSDataType.INT32);
+    TreeViewSchema.setOriginalName(test, "dev_s1");
+    final Pair<TSStatus, TsTable> result =
+        clusterSchemaManager.tableColumnCheckForColumnExtension(
+            database, viewName, new ArrayList<>(Collections.singletonList(test)), true);
+    Assert.assertEquals(TSStatusCode.SUCCESS_STATUS.getStatusCode(), result.getLeft().getCode());
+    Assert.assertNotNull(result.getRight().getColumnSchema("test"));
+  }
+
   private static ClusterSchemaManager managerOf(final ClusterSchemaInfo clusterSchemaInfo) {
     return new ClusterSchemaManager(
         Mockito.mock(IManager.class),

iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/schema/table/TreeViewSchema.java

@@ -24,6 +24,7 @@
 import org.apache.iotdb.commons.i18n.SchemaMessages;
 import org.apache.iotdb.commons.path.PartialPath;
 import org.apache.iotdb.commons.path.PathPatternUtil;
+import org.apache.iotdb.commons.schema.table.column.TsTableColumnCategory;
 import org.apache.iotdb.commons.schema.table.column.TsTableColumnSchema;
 import org.apache.iotdb.rpc.TSStatusCode;
 
@@ -86,18 +87,17 @@ public static void setOriginalName(final TsTableColumnSchema schema, final Strin
   }
 
   /**
-   * A source measurement can only be referenced once, so this set decides whether a column may
-   * still be added for one.
+   * Source measurements already referenced by the view's FIELD columns, so this set decides whether
+   * a column may still be added for one. TAG/TIME/ATTRIBUTE columns do not reference tree
+   * measurements and therefore do not occupy the source-name namespace.
    */
   public static Set<String> getSourceNames(final TsTable view) {
     final Set<String> sourceNames = new HashSet<>();
     for (final TsTableColumnSchema schema : view.getColumnList()) {
-      if (Objects.isNull(schema.getProps())) {
-        // the columns which carry no props reference their own name
-        sourceNames.add(schema.getColumnName());
-      } else {
-        sourceNames.add(getSourceName(schema));
+      if (schema.getColumnCategory() != TsTableColumnCategory.FIELD) {
+        continue;
       }
+      sourceNames.add(getSourceName(schema));
     }
     return sourceNames;
   }