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SQL, Postgres OIDs, What are they and why are they useful?

... OIDs basically give you a built-in id for every row, contained in a system column (as opposed to a user-space column). That's handy for tables where you don't have a primary key, have duplicate rows, etc. For example, if you have a t...
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[SOLVED] Can't send payload > 23bytes(MTU setted to 128bytes) - #9 by ...

.... From the app side I have a text box that is sending the string to ESP32, all working except when I try to send strings over 23bytes. Ok, I read some topics here and tried to apply those solutions but no success yet. From my ESP32 firmware I wrote: BLEDevice::init("Monitor3"); BLEDevice::setMTU(128...
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What are the underlying data structures used for Redis?

...s internals you should not care about how data types are implemented internally. This is for a simple reason: for every Redis operation you'll find the time complexity in the documentation and, if you have the set of operations and the time complexity, the only other thing you need is some clue abou...
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RAW POST using cURL in PHP

... I cannot get this to work at all. I have a page that I am trying to post raw data to. That page records all raw data it receives into a database table. There are no new rows at all. Do you know if anything has changed here since '09? ...
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Maven: how to override the dependency added by a library

...endency management that have NOT yet been implemented for Maven 2.0, especially with regards to transitive dependencies." at the top. – wishihadabettername Oct 14 '10 at 20:30 ...
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Count, size, length…too many choices in Ruby?

...1 In the case where you don't provide a parameter to count it has basically the same effect as calling length. There can be a performance difference though. We can see from the source code for Array that they do almost exactly the same thing. Here is the C code for the implementation of array.l...
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Why are elementwise additions much faster in separate loops than in a combined loop?

... Upon further analysis of this, I believe this is (at least partially) caused by the data alignment of the four-pointers. This will cause some level of cache bank/way conflicts. If I've guessed correctly on how you are allocating your arrays, they are likely to be aligned to the page line....
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How do I install an old version of Django on virtualenv?

...d question, since the very purpose of virtualenv is to this exactly: Installing some specific version of a package (in this case Django) inside the virtual environment. But it's exactly what I want to do, and I can't figure it out. ...
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Best practices around generating OAuth tokens?

...ere are any best practices for creating significantly secure tokens (especially Token/Secret combinations). 1 Answer ...
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Reading output of a command into an array in Bash

...tput of a command in an array, with one line per element, there are essentially 3 ways: With Bash≥4 use mapfile—it's the most efficient: mapfile -t my_array < <( my_command ) Otherwise, a loop reading the output (slower, but safe): my_array=() while IFS= read -r line; do my_array+...