SELECT
*
FROM
tb_feature?tf
LEFT?JOIN?tb_feature_package?tfp?ON?(
tfp.FEATURE_SID?=?tf.SID
AND?tfp.PACKAGE_SID?=?430
)
LEFT?JOIN?tb_family?tfy?ON?(tf.FAMILY_SID?=?tfy.sid)
WHERE
tf.FOCUS_FLAG?=?1
?AND?tf.VERSION_SID?=?140
and??tfp.PACKAGE_SID?is?not?null
GROUP?BY
tf.FEATURE_CODE用了有什么特別意義么
請(qǐng)解釋這句sql的group by的含義
car
2017-06-11 14:53:55
