大约有 40,000 项符合查询结果（耗时：0.0537秒） [XML]
Change one value based on another value in pandas
...we are adding a new description column as a concatenation of other columns by using the + operation which is overridden for series. Fancy string formatting, f-strings etc won't work here since the + applies to scalars and not 'primitive' values:
df['description'] = 'A ' + df.age.astype(str) + ' yea...
Is it possible to GROUP BY multiple columns using MySQL?
Is it possible to GROUP BY more than one column in a MySQL SELECT query? For example:
7 Answers
...
Difference between and
...red in the application context (no matter if they were defined with XML or by package scanning).
<context:component-scan> can also do what <context:annotation-config> does but <context:component-scan> also scans packages to find and register beans within the application context.
...
How can I get device ID for Admob
...
You can try to find key by "RequestConfiguration.Builder().setTestDeviceIds"
– hidd
Sep 23 at 18:01
add a comment
...
Is there a way to loop through a table variable in TSQL without using a cursor?
...able. I don't believe the normal downsides of cursors applies here. If row-by-row processing is truly required (and as you point out he should be certain about that first) then using a cursor is a much better solution than the ones you describe here.
– peterh
J...
How to define object in array in Mongoose schema correctly with 2d geo index
...
You can declare trk by the following ways : -
either
trk : [{
lat : String,
lng : String
}]
or
trk : { type : Array , "default" : [] }
In the second case during insertion make the object and push it into the array like
db.u...
Splitting string into multiple rows in Oracle
...
This may be an improved way (also with regexp and connect by):
with temp as
(
select 108 Name, 'test' Project, 'Err1, Err2, Err3' Error from dual
union all
select 109, 'test2', 'Err1' from dual
)
select distinct
t.name, t.project,
trim(regexp_substr(t.error, '[^,]+...
Cast an instance of a class to a @protocol in Objective-C
...ing to cast to the specific object. So, I would recommend using the answer by @andy anywhere you are casting to a protocol instead of the above -- id<MyProtocol> p = (id<MyProtocol>)self.myViewController; This answer and @andys are both correct, but his is more correct.
...
Insert into a MySQL table or update if exists
... manual that updates in ON DUPLICATE KEY UPDATE increase the affected rows by 2. It reports 0 if nothing is actually updated (same as the regular UPDATE).
– Vatev
Mar 31 '14 at 11:53
...
Migration: Cannot add foreign key constraint
...table. Migrations get executed in the order they were created as indicated by the file name generated after running migrate:make. E.g. 2014_05_10_165709_create_student_table.php.
The solution was to rename the file with the foreign key to an earlier time than the file with the primary key as recomm...