在Oracle数据库中，可以使用以下几种方法来查询表中的行数：
SELECT COUNT(*) FROM table_name;
SELECT COUNT(1) FROM table_name;
ANALYZE TABLE table_name COMPUTE STATISTICS;
SELECT num_rows FROM user_tables WHERE table_name = 'table_name';
SELECT num_rows FROM dba_tables WHERE table_name = 'table_name';
SELECT table_name, num_rows FROM user_tab_statistics WHERE table_name = 'table_name';
