大约有 4,000 项符合查询结果（耗时：0.0241秒） [XML]
How can I combine multiple rows into a comma-delimited list in Oracle? [duplicate]
...('Antigua');
SELECT SUBSTR (SYS_CONNECT_BY_PATH (country_name , ','), 2) csv
FROM (SELECT country_name , ROW_NUMBER () OVER (ORDER BY country_name ) rn,
COUNT (*) OVER () cnt
FROM countries)
WHERE rn = cnt
START WITH rn = 1
CONNECT BY rn = PRIOR rn + 1;
...
Postgresql GROUP_CONCAT equivalent?
...method, if they are not desired.
Casting ANYARRAY to TEXT best simulates CSV output as elements that contain embedded commas are double-quoted in the output in standard CSV style. Neither array_to_string() or string_agg() (the "group_concat" function added in 9.1) quote strings with embedded comma...
MySQL dump by query
...
You can dump a query as csv like this:
SELECT * from myTable
INTO OUTFILE '/tmp/querydump.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
share
...
Filtering Pandas DataFrames on dates
...
So when loading the csv data file, we'll need to set the date column as index now as below, in order to filter data based on a range of dates. This was not needed for the now deprecated method: pd.DataFrame.from_csv().
If you just want to show ...
Android中Java和JavaScript交互 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...，对于简单的类型会尝试转换成字符串返回，对于复杂的数据类型，建议以字符串形式的json返回。
evaluateJavascript方法必须在UI线程（主线程）调用，因此onReceiveValue也执行在主线程。
疑问解答
Alert无法弹出
你应该是没有设...
reformat in vim for a nice column layout
I have this dataset in a csv file
13 Answers
13
...
returning in the middle of a using block
...(var textwriter = new StreamWriter(memoryStream))
{
using (var csv = new CsvWriter(textwriter))
{
//..write some stuff to the stream using the CsvWriter
return memoryStream.ToArray();
}
}
}
I was passing in a DataTable to be outputted as csv....
Combine Date and Time columns using python pandas
...ou may have been able to read this in directly e.g. if you were using read_csv using parse_dates=[['Date', 'Time']].
Assuming these are just strings you could simply add them together (with a space), allowing you to apply to_datetime:
In [11]: df['Date'] + ' ' + df['Time']
Out[11]:
0 01-06-2013...
Sorting multiple keys with Unix sort
...
Here is one to sort various columns in a csv file by numeric and dictionary order, columns 5 and after as dictionary order
~/test>sort -t, -k1,1n -k2,2n -k3,3d -k4,4n -k5d sort.csv
1,10,b,22,Ga
2,2,b,20,F
2,2,b,22,Ga
2,2,c,19,Ga
2,2,c,19,Gb,hi
2,2,c,19,Gb,hj
2,...
Pandas every nth row
...came up with when using the index was not viable ( possibly the multi-Gig .csv was too large, or I missed some technique that would allow me to reindex without crashing ).
Walk through one row at a time and add the nth row to a new dataframe.
import pandas as pd
from csv import DictReader
def make_...