使用MySQL,我可以做类似的事情:SELECT hobbies FROM peoples_hobbies WHERE person_id=5;我的输出:shopping fishing coding 但是我只想要1行1列:预期产量:shopping,fishing,coding 原因是我要从多个表中选择多个值,并且在所有联接...
aa表 mysql>select*from aa;id|name|other|+-+-+-+|1|asdf|dfdfd|2|sdf|fdfd|3|dfasdf|dfdasd|4|fasdf|fdasd|5|asdf|dasd|6|bsdf|hell0|+-+-+-+联合索引 mysql>show index from aa;Table|Non_unique|Key_name|Seq_in_index|Column_name|...