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Which timestamp type should I choose in a PostgreSQL database?
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First off, PostgreSQL’s time handling and arithmetic is fantastic and Option 3 is fine in the general case. It is, however, an incomplete view of time and timezones and can be supplemented:
Store the name of a user’s time zone as a user preference (e....
Eclipse syntax highlighting preferences save and restore
...henever I try to export these settings via File|Export|General|Preferences and reimport them, the settings never completely get imported back. Some colors are restored and others are left unchanged, leaving me in an 'in between' state - very frustrating.
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Finding duplicate values in MySQL
I have a table with a varchar column, and I would like to find all the records that have duplicate values in this column. What is the best query I can use to find the duplicates?
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Why do we need a pure virtual destructor in C++?
I understand the need for a virtual destructor. But why do we need a pure virtual destructor? In one of the C++ articles, the author has mentioned that we use pure virtual destructor when we want to make a class abstract.
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MySQL error: key specification without a key length
...r BLOB types such as TINYBLOB, MEDIUMBLOB, LONGBLOB, TINYTEXT, MEDIUMTEXT, and LONGTEXT that you try to make a primary key or index. With full BLOB or TEXT without the length value, MySQL is unable to guarantee the uniqueness of the column as it’s of variable and dynamic size. So, when using BLOB ...
In what situations would AJAX long/short polling be preferred over HTML5 WebSockets?
...sends request headers with optional data, gets a response from the server, and closes the connection.
Supported in all major browsers.
Long poll - request → wait → response. Creates a connection to the server like AJAX does, but maintains a keep-alive connection open for some time (not long tho...
SQL Server - Create a copy of a database table and place it in the same database?
...is will create a new table ABC_1 that has the same column structure as ABC and contains the same data. Constraints (e.g. keys, default values), however, are -not- copied.
You can run this query multiple times with a different table name each time.
If you don't need to copy the data, only to cre...
Composer: how can I install another dependency without updating old ones?
I have a project with a few dependencies and I'd like to install another one, but I'd like to keep the others the way they are. So I've edited the composer.json , but if I run composer install , I get the following output:
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RESTful way to create multiple items in one request
... resources.
Example, imagine that we have an endpoint like /api/sheep/{id} and we can POST to /api/sheep to create a sheep resource.
Now, if we want to support bulk creation, we should consider a new flock resource at /api/flock (or /api/<your-resource>-collection if you lack a better meaning...
C++ Tuple vs Struct
Is there is any difference between using a std::tuple and a data-only struct ?
12 Answers
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