使用select查询时,各子句(from、where、order、on、limit)的位置规则
2018-03-01 18:35
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每次看数据库的一些语法时,都很自然的略过那一大堆的规则,比如说线下面这段select的语法:
select [field1,field2...] func_name
实际用的时候,除非经常使用,有些项顺序已经习以为常了,但是更多的时候,总会将顺序搞错,比如group
select [field1,field2...] func_name
from table1
[left|right join table2 on condition_what]
[where condition_where]
[group by field1,field2...]
[with rollup]
[having condition_where]
[order by field1 [desc|asc]]
[limit offset,length]
实际用的时候,除非经常使用,有些项顺序已经习以为常了,但是更多的时候,总会将顺序搞错,比如group
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