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ActiveRecord: size vs count
...l valid.
You'll adapt the function you use depending on your needs.
Basically:
if you already load all entries, say User.all, then you should use length to avoid another db query
if you haven't anything loaded, use count to make a count query on your db
if you don't want to bother with these con...
How can I put a database under git (version control)?
... and version control that instead. This way it is a flat text file.
Personally I suggest that you keep both a data dump, and a schema dump. This way using diff it becomes fairly easy to see what changed in the schema from revision to revision.
If you are making big changes, you should have a secon...
Why does the PHP json_encode function convert UTF-8 strings to hexadecimal entities?
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Since PHP/5.4.0, there is an option called JSON_UNESCAPED_UNICODE. Check it out:
https://php.net/function.json-encode
Therefore you should try:
json_encode( $text, JSON_UNESCAPED_UNICODE );
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Scala: join an iterable of strings
...,"): String = list match { case head :: tail => tail.foldLeft(head)(_ + delim + _) case Nil => "" }
– Davos
Jul 11 '17 at 14:37
2
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Maximum single-sell profit
...oblem in each subarray, then combining the two together. Turns out we actually can do this, and can do so efficiently! The intuition is as follows. If we have a single day, the best option is to buy on that day and then sell it back on the same day for no profit. Otherwise, split the array into ...
Servlet returns “HTTP Status 404 The requested resource (/servlet) is not available”
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Put servlet class in a package
First of all, put the servlet class in a Java package. You should always put publicly reuseable Java classes in a package, otherwise they are invisible to classes which are in a package, such as the server itself. This way you elimini...
Tools for JPEG optimization? [closed]
Do you know of any tools (preferrably command-line) to automatically and losslessly optimize JPEGs that I could integrate into our build environment? For PNGs I'm currently using PNGOUT , and it generally saves around 40% bandwidth/image size.
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Is Dvorak typing appropriate for programming? [closed]
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There are Dvorak layouts specifically for programming: http://www.kaufmann.no/roland/dvorak/
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How to define a two-dimensional array?
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You're technically trying to index an uninitialized array. You have to first initialize the outer list with lists before adding items; Python calls this
"list comprehension".
# Creates a list containing 5 lists, each of 8 items, all set t...
Android file chooser [closed]
...tent in an Intent.createChooser() like this:
private static final int FILE_SELECT_CODE = 0;
private void showFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
try {
startActivityFor...