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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...em in useful detail.
In general you must choose between two options:
Individual insert/update operations in a retry loop; or
Locking the table and doing batch merge
Individual row retry loop
Using individual row upserts in a retry loop is the reasonable option if you want many connections concurre...
How to implement Android Pull-to-Refresh
In Android applications such as Twitter (official app), when you encounter a ListView, you can pull it down (and it will bounce back when released) to refresh the content.
...
LINQ - Full Outer Join
I have a list of people's ID and their first name, and a list of people's ID and their surname. Some people don't have a first name and some don't have a surname; I'd like to do a full outer join on the two lists.
...
Retrieving the last record in each group - MySQL
..._messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solution this way:
SELECT m1.*
FROM messages m1 LEFT JOIN mes...
How to filter SQL results in a has-many-through relation
...fe data.)
Slight diversion from the naming schema in the question: student.id is student.stud_id and club.id is club.club_id here.
I named the queries after their author in this thread, with an index where there are two.
I ran all queries a couple of times to populate the cache, then I picked the be...
MySQL Insert into multiple tables? (Database normalization?)
...s (username, password)
VALUES('test', 'test');
INSERT INTO profiles (userid, bio, homepage)
VALUES(LAST_INSERT_ID(),'Hello world!', 'http://www.stackoverflow.com');
COMMIT;
Have a look at LAST_INSERT_ID() to reuse autoincrement values.
Edit: you said "After all this time trying to figure it ...
What is the difference between save and insert in Mongo DB?
...s essentially the same.
save behaves differently if it is passed with an "_id" parameter.
For save, If the document contains _id, it will upsert querying the collection on the _id field, If not, it will insert.
If a document does not exist with the specified _id value, the save() method performs an...
How to get the device's IMEI/ESN programmatically in android?
To identify each devices uniquely I would like to use the IMEI (or ESN number for CDMA devices). How to access this programmatically?
...
Array vs. Object efficiency in JavaScript
...icient way of storing them and retrieving a single object once I have it's id. The id's are long numbers.
9 Answers
...
Custom method names in ASP.NET Web API
...T request to /api/users/authenticate you are basically calling the Get(int id) action and passing id=authenticate which obviously crashes because your Get action expects an integer.
If you want to have different action names than the standard ones you could modify your route definition in global.as...
