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Count with IF condition in MySQL query
...unt()
Try below:
SELECT
ccc_news . * ,
SUM(if(ccc_news_comments.id = 'approved', 1, 0)) AS comments
FROM
ccc_news
LEFT JOIN
ccc_news_comments
ON
ccc_news_comments.news_id = ccc_news.news_id
WHERE
`ccc_news`.`category` = 'news_layer2'
AND `ccc_news`.`sta...
Android read text raw resource file
...ered Apr 15 '11 at 11:22
VovodroidVovodroid
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Wildcards in jQuery selectors
I'm trying to use a wildcard to get the id of all the elements whose id begin with "jander". I tried $('#jander*') , $('#jander%') but it doesn't work..
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How to use querySelectorAll only for elements that have a specific attribute set?
...ell me what is this syntax input[value][type="checkbox"]:not([value=""] i didnt see this syntax like this before in javascript
– blackHawk
Aug 18 '16 at 9:10
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How to declare a variable in a PostgreSQL query
...
This is ideal for when I have a migration script where I want to import some relational data. Obviously I won't know the sequence id the relational data is given.
– Relequestual
Feb 13 '15 at 9:...
Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...he primitive type from the getter. Ex:
private Integer num;
public void setNum(Integer i) {
this.num = i;
}
public int getNum() {
return this.num;
}
But in most cases you will want to return the wrapper class.
So either set your DB column to not allow nulls, or use a wrapper ...
jquery IDs with spaces
Does anyone know how to select an item in the DOM by ID with jQuery, when that ID has a space?
11 Answers
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Validate uniqueness of multiple columns
Is there a rails-way way to validate that an actual record is unique and not just a column? For example, a friendship model / table should not be able to have multiple identical records like:
...
How can I convert this foreach code to Parallel.ForEach?
... Just wanted to point it out (more for the OP) so that there wasn't a misguided thought that it only works on List<T> ;)
– Reed Copsey
Sep 3 '12 at 17:21
1
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...:
SELECT * FROM Cars;
And then for each Car:
SELECT * FROM Wheel WHERE CarId = ?
In other words, you have one select for the Cars, and then N additional selects, where N is the total number of cars.
Alternatively, one could get all wheels and perform the lookups in memory:
SELECT * FROM Wheel
Thi...