大约有 40,000 项符合查询结果（耗时：0.0327秒） [XML]
Pandas count(distinct) equivalent
...
I believe this is what you want:
table.groupby('YEARMONTH').CLIENTCODE.nunique()
Example:
In [2]: table
Out[2]:
CLIENTCODE YEARMONTH
0 1 201301
1 1 201301
2 2 201301
3 1 201302
4 2 ...
PHP PDO returning single row
...-- connection string --- ");
$stmt = $dbh->prepare("SELECT name FROM mytable WHERE id=4 LIMIT 1");
$stmt->execute();
$row = $stmt->fetch();
share
|
improve this answer
|
...
How do I join two SQLite tables in my Android application?
I have an Android project that has a database with two tables: tbl_question and tbl_alternative .
4 Answers
...
How to query MongoDB with “like”?
... Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what's happening.
– Kyle Banker
J...
LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
... M=4; N=2; seed=1234567;
enddata
sets:
rows/1..M/;
cols/1..N/;
table(rows,cols): x;
endsets
data:
X=@qrand(seed);
enddata
end
如果没有为函数指定种子，那么LINGO将用系统时间构造种子。
14．@rand(seed)
返回0和1间的伪随机数，依赖于指定的种...
Relative frequencies / proportions with dplyr
...our depending on the version of dplyr:
dplyr 0.7.1: returns an ungrouped table: you need to group again by am
dplyr < 0.7.1: returns a grouped table, so no need to group again, although you might want to ungroup() for later manipulations
dplyr 0.7.1
mtcars %>%
count(am, gear) %>%
g...
select count(*) from table of mysql in php
...
here is the code for showing no of rows in the table with PHP
$sql="select count(*) as total from student_table";
$result=mysqli_query($con,$sql);
$data=mysqli_fetch_assoc($result);
echo $data['total'];
...
How do I find an element that contains specific text in Selenium Webdriver (Python)?
...substitutes a source character to its desired form, by using a translation table.
Constructing a table of all upper case characters will effectively transform the node's text to its lower() form - allowing case-insensitive matching (here's just the prerogative):
[
contains(
translate(text(),...
Having a UITextField in a UITableViewCell
...o, I'm still unable to have a fully working UITextField in some of my UITableViewCells , just like in this example:
12 ...
SQL Server: Make all UPPER case to Proper Case/Title Case
I have a table that was imported as all UPPER CASE and I would like to turn it into Proper Case. What script have any of you used to complete this?
...