大约有 40,000 项符合查询结果（耗时：0.0271秒） [XML]
How to check if mysql database exists
...
SELECT SCHEMA_NAME
FROM INFORMATION_SCHEMA.SCHEMATA
WHERE SCHEMA_NAME = 'DBName'
If you just need to know if a db exists so you won't get an error when you try to create it, simply use (From here):
CREATE DATABASE IF NO...
Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
...
Eclipse git checkout (aka, revert)
...ing" view, right click the deleted file in the "Unstaged Changes" list and select "Replace with HEAD Revision"
– Vlasta Dolejs
Sep 5 '17 at 8:03
add a comment
...
Equivalent of LIMIT and OFFSET for SQL Server?
...nation it's better to write a query like this:
;WITH Results_CTE AS
(
SELECT
Col1, Col2, ...,
ROW_NUMBER() OVER (ORDER BY SortCol1, SortCol2, ...) AS RowNum
FROM Table
WHERE <whatever>
)
SELECT *
FROM Results_CTE
WHERE RowNum >= @Offset
AND RowNum < @Offset +...
Capitalize first letter. MySQL
...
You can use a combination of UCASE(), MID() and CONCAT():
SELECT CONCAT(UCASE(MID(name,1,1)),MID(name,2)) AS name FROM names;
share
|
improve this answer
|
...
Linq: GroupBy, Sum and Count
...a" is coming from, but the problem in the console app is that you're using SelectMany to look at each item in each group.
I think you just want:
List<ResultLine> result = Lines
.GroupBy(l => l.ProductCode)
.Select(cl => new ResultLine
{
ProductName =...
Eclipse: How do you change the highlight color of the currently selected method/expression?
...from the Annotation types list.
Then, be sure that Text as highlighted is selected, then choose the desired color.
And, a picture is worth a thousand words...
(source: coobird.net)
(source: coobird.net)
share
...
Obtain form input fields using jQuery?
...s[field.name] = field.value;
});
Note that this snippet will fail on <select multiple> elements.
It appears that the new HTML 5 form inputs don't work with serializeArray in jQuery version 1.3. This works in version 1.4+
...
Read data from SqlDataReader
...you use indexes like reader.GetString(0) will it use the first column you selected in your query or the firstt column on the table. I have a table with 3 columns in order: ID, Dir, Email. My command selects dir and email. Will reader.GetStrting(0) retrieve dir or ID? Are the indexes based off t...
Set cache-control for entire S3 bucket automatically (using bucket policies?)
...it can take some time.
Log in to AWS Management Console
Go into S3 bucket
Select all files by route
Choose "More" from the menu
Select "Change metadata"
In the "Key" field, select "Cache-Control" from the drop down menu
max-age=604800Enter (7 days) for Value
Press "Save" button
(thanks to @biplob ...