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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...
In which case do you use the JPA @JoinTable annotation?
...le named Task and add a foreign key column to the task table named project_id:
Project Task
------- ----
id id
name name
project_id
This way, it will be possible to determine the project for each row in the task table. If you use this approach, in your en...
REST API Best practices: Where to put parameters? [closed]
...nted best practices, I have not found them yet. However, here are a few guidelines I use when determining where to put parameters in an url:
Optional parameters tend to be easier to put in the query string.
If you want to return a 404 error when the parameter value does not correspond to an exist...
Converting JSON data to Java object
... Google's Gson as a potential JSON plugin. Can anyone offer some form of guidance as to how I can generate Java from this JSON string?
Google Gson supports generics and nested beans. The [] in JSON represents an array and should map to a Java collection such as List or just a plain Java array. The ...
How do you install ssh-copy-id on a Mac?
I am having trouble trying to install ssh-copy-id on my Mac. I have tried to follow https://github.com/beautifulcode/ssh-copy-id-for-OSX but every time I run ssh-copy-id it gives me errors. Any ideas on how to get ssh-copy-id to install?
...
Delete all Duplicate Rows except for One in MySQL? [duplicate]
...e.
NB - You need to do this first on a test copy of your table!
When I did it, I found that unless I also included AND n1.id <> n2.id, it deleted every row in the table.
If you want to keep the row with the lowest id value:
DELETE n1 FROM names n1, names n2 WHERE n1.id > n2.id AND n...
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 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:...
How to add facebook share button on my website?
...
Important note: This idea on mobile opens the Facebook website (Not FB app). Little (Or big) con.
– Ezra Siton
Apr 9 at 16:07
...
Show and hide a View with a slide up/down animation
I have a LinearLayout that I want to show or hide with an Animation that pushes the layout upwards or downwards whenever I change its visibility.
...