does the existence of an asterisk in a select exclude other columns?(选择中存在星号是否排除其他列?)
问题描述
This question is all about laziness... I'd like to do something like this:
select some_func(some_col), * from my_table
So that I don't have to do this:
select some_func(some_col), col_1, col_2... col_ad_infinitum from my_table
Is there any way to make the first query work? This is the error I get when I run it:
ERROR 1064 (42000) at line 1: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '* from my_table' at line 1
Do you mean that in MySQL your first query:
SELECT some_func(some_col), *
FROM my_table
produces this error?:
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '*' at line 1
You can change your code into (this results in no errors!):
SELECT *, some_func(some_col)
FROM my_table
or into this, if you want to have the calculated columns first:
SELECT some_func(some_col), t.*
FROM my_table AS t
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本文标题为:选择中存在星号是否排除其他列?
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