大约有 47,000 项符合查询结果（耗时：0.0285秒） [XML]
What is the most compatible way to install python modules on a Mac?
...o for MacPorts be aware that multiple versions of the same package are not selected anymore like the old Debian style with an extra python_select package (it is still there for compatibility). Now you have the select command to choose which Python version will be used (you can even select the Apple ...
Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
How to extract year and month from date in PostgreSQL without using to_char() function?
I want to select sql:
SELECT "year-month" from table group by "year-month" AND order by date , where
year-month - format for date "1978-01","1923-12".
select to_char of couse work , but not "right" order:
...
How to insert text at beginning of a multi-line selection in vi/Vim
In Vim , how do I insert characters at the beginning of each line in a selection?
13 Answers
...
Easiest way to copy a table from one database to another?
...
CREATE TABLE db1.table1 SELECT * FROM db2.table1
where db1 is the destination and db2 is the source
share
|
improve this answer
|
...
How to pass an array into a SQL Server stored procedure
...WithEmployees
@List AS dbo.IDList READONLY
AS
BEGIN
SET NOCOUNT ON;
SELECT ID FROM @List;
END
GO
Now in your C# code:
// Obtain your list of ids to send, this is just an example call to a helper utility function
int[] employeeIds = GetEmployeeIds();
DataTable tvp = new DataTable();
tvp.C...
Selecting a row of pandas series/dataframe by integer index
...
The primary purpose of the DataFrame indexing operator, [] is to select columns.
When the indexing operator is passed a string or integer, it attempts to find a column with that particular name and return it as a Series.
So, in the question above: df[2] searches for a column name matchin...
Eclipse: All my projects disappeared from Project Explorer
...Do File->Import
General->Existing Projects into Workspace
Click the "Select root directory" field and browse to each subfolder in your workspace folder, and import.
For me, this was very tedious, since I had several dozen projects in my workspace, but it's the only solution I found short of ...
Is SQL or even TSQL Turing Complete?
...(0);
-- Initialization of temporary variables
DECLARE @CodeLength INT = (SELECT COUNT(*) FROM @CodeTable);
DECLARE @CodeIndex INT = 0;
DECLARE @Pointer INT = 1;
DECLARE @InputIndex INT = 0;
DECLARE @Command CHAR(1);
DECLARE @Depth INT;
-- Main calculation cycle
WHILE @CodeIndex < @...
How to fix Error: “Could not find schema information for the attribute/element” by creating schema
...tudio, open your app.config or web.config file.
Go to the "XML" menu and select "Create Schema". This action should create a new file called "app.xsd" or "web.xsd".
Save that file to your disk.
Go back to your app.config or web.config and in the edit window, right click and select properties. From...