content: package com.alibaba.druid.bvt.sql.mysql.issues;
  
  import com.alibaba.druid.DbType;
  import com.alibaba.druid.sql.ast.SQLStatement;
  import com.alibaba.druid.sql.parser.SQLParserUtils;
  import com.alibaba.druid.sql.parser.SQLStatementParser;
  import org.junit.Test;
  
  import static org.junit.Assert.assertEquals;
  
  /**
   * 验证 ALTER TABLE t1 ALTER INDEX i_idx INVISIBLE语法
   *
   * @author lizongbo
   * @see <a href="https://github.com/alibaba/druid/issues/5650">Issue来源</a>
   */
  public class Issue5650 {
      @Test
      public void test_alter_index() throws Exception {
          for (DbType dbType : new DbType[]{DbType.mysql}) {
              for (String sql : new String[]{
                  "ALTER TABLE t1 ALTER INDEX i_idx INVISIBLE;",
                  "ALTER TABLE t1 ALTER INDEX i_idx VISIBLE;",
              }) {
                  SQLStatementParser parser = SQLParserUtils.createSQLStatementParser(sql, dbType);
                  SQLStatement statement = parser.parseStatement();
                  System.out.println(dbType + "原始的sql===" + sql);
                  System.out.println(dbType + "归一化的sql===" + Issue5421.normalizeSql(sql));
                  String newSql = statement.toString() + ";";
                  System.out.println(dbType + "生成的sql===" + newSql);
                  System.out.println(dbType + "生成的sql归一化===" + Issue5421.normalizeSql(newSql));
                  parser = SQLParserUtils.createSQLStatementParser(newSql, dbType);
                  statement = parser.parseStatement();
                  System.out.println(dbType + "再次解析对象得到sql===" + Issue5421.normalizeSql(statement.toString()));
                  assertEquals(sql, Issue5421.normalizeSql(statement.toString()));
              }
          }
      }
  }
  