大约有 48,000 项符合查询结果（耗时：0.0202秒） [XML]
Selecting only numeric columns from a data frame
...traightforward, and robust to use on database-back-ended tibbles:
dplyr::select_if(x, is.numeric)
share
|
improve this answer
|
follow
|
...
tmux set -g mouse-mode on doesn't work
...n. There's now no longer options for:
- mouse-resize-pane
- mouse-select-pane
- mouse-select-window
- mode-mouse
Instead there is just one option: 'mouse' which turns on mouse support
So this is what I'm using now in my .tmux.conf file
set -g mouse on
...
Is there a better way to dynamically build an SQL WHERE clause than by using 1=1 at its beginning?
... {2}", clause, appender, condition);
}
Use it like this
string query = "SELECT * FROM Table1 {0}";
string whereClause = string.Empty;
if (condition 1)
whereClause = AddCondition(whereClause, "AND", "Col=1");
if (condition 2)
whereClause = AddCondition(whereClause, "AND", "Col2=2");
str...
How do I set the selected item in a comboBox to match my string using C#?
..." and my comboBox contains test1 , test2 , and test3 . How do I set the selected item to "test1"? That is, how do I match my string to one of the comboBox items?
...
How to select multiple files with ?
How to select multiple files with <input type="file"> ?
9 Answers
9
...
How can I make an entire HTML form “readonly”?
...e="text" name="something" placeholder="enter some text" />
<select>
<option value="0" disabled="disabled" selected="selected">select somethihng</option>
<option value="1">woot</option>
<option value="2">is</opt...
Run an app on a multiple devices automatically in Android Studio
...
if you shold shift, select all devices, and you click "Run on the same device next time", even if it doesn't' put plural "devices" it will automatically run on all the next time.
– OWADVL
Oct 28 '14 at 10:2...
Check if a Postgres JSON array contains a string
...
As of PostgreSQL 9.4, you can use the ? operator:
select info->>'name' from rabbits where (info->'food')::jsonb ? 'carrots';
You can even index the ? query on the "food" key if you switch to the jsonb type instead:
alter table rabbits alter info type jsonb using ...
PostgreSQL create table if not exists
..._mytable()
RETURNS void
LANGUAGE plpgsql AS
$func$
BEGIN
IF EXISTS (SELECT FROM pg_catalog.pg_tables
WHERE schemaname = 'myschema'
AND tablename = 'mytable') THEN
RAISE NOTICE 'Table myschema.mytable already exists.';
ELSE
CREATE TABLE myschema...
Distinct in Linq based on only one field of the table
...
Try this:
table1.GroupBy(x => x.Text).Select(x => x.FirstOrDefault());
This will group the table by Text and use the first row from each groups resulting in rows where Text is distinct.
...