效率问题(怎么这么慢)
SELECT
`zsxt_shpfxsh`.`功能`,
MIN(`zsxt_shpfxsh`.`单价`) AS `FIELD_1`,
MAX(`zsxt_shpfxsh`.`单价`) AS `FIELD_1`,
AVG(`zsxt_shpfxsh`.`单价`) AS `FIELD_1`
FROM
`zsxt_xmshqsh`
INNER JOIN `zsxt_shpfxsh` ON (`zsxt_xmshqsh`.`许可证号` = `zsxt_shpfxsh`.`许可证号`)
WHERE
(`成交日期` >= '2003-11-25') AND
(`成交日期` < '2003-12-25') AND
(`单价` > 0)
GROUP BY
`zsxt_shpfxsh`.`功能`
ORDER BY
`成交日期`
这个SQL怎么比ACCESS都慢几十倍(记录有zsxt_xmshqsh3000条zsxt_shpfxsh500000多条)