oracle 根据时间字段查询数据
ROWNUM 是对前面查询的记录做限制，比如查询的记录 > 2000 条，那么只取前面的 2000 条
'''
SELECT * FROM
(SELECT CLXXBH, JGSK, CDBH, HPHM, HPYS, SBBH, KKMC, WD, JD, CLLX, CSYS, HPZL, CLSD, WFXW, HPTP, QJTP, RKSJ, XSFX, KKID
FROM WFXX.WFXX
WHERE RKSJ >= TO_DATE('%s', 'YYYY/MM/DD HH24:MI:SS')
AND RKSJ < TO_DATE('%s', 'YYYY/MM/DD HH24:MI:SS')
ORDER BY RKSJ)
WHERE ROWNUM <= 2000
'''