support interval alias

src/main/java/com/alibaba/druid/sql/parser/SQLParser.java

@@ -170,6 +170,7 @@ public class SQLParser {
 
         switch (lexer.token()) {
             case KEY:
+            case INTERVAL:
                 alias = lexer.token().name();
                 lexer.nextToken();
                 return alias;

src/test/java/com/alibaba/druid/bvt/sql/oracle/OracleSelectTest52.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 1999-2011 Alibaba Group Holding Ltd.
+ *
+ * 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
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 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.alibaba.druid.bvt.sql.oracle;
+
+import java.util.List;
+
+import org.junit.Assert;
+
+import com.alibaba.druid.sql.OracleTest;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.oracle.parser.OracleStatementParser;
+import com.alibaba.druid.sql.dialect.oracle.visitor.OracleSchemaStatVisitor;
+import com.alibaba.druid.sql.test.TestUtils;
+
+public class OracleSelectTest52 extends OracleTest {
+
+    public void test_0() throws Exception {
+        String sql = //
+        "select 1 interval from dual"; //
+
+        OracleStatementParser parser = new OracleStatementParser(sql);
+        List<SQLStatement> statementList = parser.parseStatementList();
+        SQLStatement stmt = statementList.get(0);
+        print(statementList);
+
+        Assert.assertEquals(1, statementList.size());
+
+        OracleSchemaStatVisitor visitor = new OracleSchemaStatVisitor();
+        stmt.accept(visitor);
+
+        System.out.println("Tables : " + visitor.getTables());
+        System.out.println("fields : " + visitor.getColumns());
+        System.out.println("coditions : " + visitor.getConditions());
+        System.out.println("relationships : " + visitor.getRelationships());
+        System.out.println("orderBy : " + visitor.getOrderByColumns());
+
+        Assert.assertEquals(0, visitor.getTables().size());
+
+        Assert.assertEquals(0, visitor.getColumns().size());
+
+        String text = TestUtils.outputOracle(stmt);
+
+        Assert.assertEquals("SELECT 1 AS INTERVAL" //
+                            + "\nFROM dual;"//
+                            + "\n", text);
+
+        // Assert.assertTrue(visitor.getColumns().contains(new TableStat.Column("acduser.vw_acd_info", "xzqh")));
+
+        // Assert.assertTrue(visitor.getOrderByColumns().contains(new TableStat.Column("employees", "last_name")));
+    }
+}