大约有 48,000 项符合查询结果（耗时：0.0344秒） [XML]
Count the occurrences of DISTINCT values
...
SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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MYSQL OR vs IN performance
...for future Googlers. Total count of returned results is 7264 out of 10000
SELECT * FROM item WHERE id = 1 OR id = 2 ... id = 10000
This query took 0.1239 seconds
SELECT * FROM item WHERE id IN (1,2,3,...10000)
This query took 0.0433 seconds
IN is 3 times faster than OR
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How may I reference the script tag that loaded the currently-executing script?
...wsers and IE.
Does not work with modules <script type="module">
2. Select script by id
Giving the script an id attribute will let you easily select it by id from within using document.getElementById().
<script id="myscript">
var me = document.getElementById('myscript');
</script&...
Want to find records with no associated records in Rails
... get everyone with no friends in the first case:
Person.where('id NOT IN (SELECT DISTINCT(person_id) FROM friends)')
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Get Specific Columns Using “With()” Function in Laravel Eloquent
... like
Post::with(array('user'=>function($query){
$query->select('id','username');
}))->get();
It will only select id and username from other table. I hope this will help others.
Remember that the primary key (id in this case) needs to be the first param in the
$query->s...
java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener
...rties (e.g., right-click on the project's name in the project explorer and select "Properties").
Select "Deployment Assembly".
Click the "Add..." button on the right margin.
Select "Java Build Path Entries" from the menu of Directive Type and click "Next".
Select "Maven Dependencies" from the Java B...
Find the host name and port using PSQL commands
...
SELECT *
FROM pg_settings
WHERE name = 'port';
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Duplicate and rename Xcode project & associated folders [closed]
...ame or any associated folders at this stage.
In Xcode, rename the project. Select your project from the navigator pane (left pane). In the Utilities pane (right pane) rename your project, Accept the changes Xcode proposes.
In Xcode, rename the schemes in "Manage Schemes", also rename any targets you...
JPA : How to convert a native query result set to POJO class collection
...e done with an entity.
For instance:
Query query = em.createNativeQuery("SELECT name,age FROM jedi_table", Jedi.class);
@SuppressWarnings("unchecked")
List<Jedi> items = (List<Jedi>) query.getResultList();
But in this case, Jedi, must be a mapped entity class.
An alternative to avoi...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...f these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.
For more guidance on this, see:
:help :map
:help :noremap
:help recursi...