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Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
How to remove constraints from my MySQL table?
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Postgres, MSSQL, and Oracle all have alter table .. drop constraint. MySQL is the odd one out, it seems.
– Jared Beck
Mar 23 '15 at 23:48
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Laravel migration: unique key is too long, even if specified
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Specify a smaller length for your e-mail:
$table->string('email', 250);
Which is the default, actually:
$table->string('email');
And you should be good.
For Laravel 5.4 you can find a solution in this Laravel 5.4: Specified ...
Read-only and non-computed variable properties in Swift
...g in Objective-C. I have readonly properties, and they cannot be individually changed. However, using a specific method, the properties are changed in a logical way.
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List of special characters for SQL LIKE clause
What is the complete list of all special characters for a SQL (I'm interested in SQL Server but other's would be good too) LIKE clause?
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ios app maximum memory budget
...ered your own question: try not to go beyond the 70 Mb limit, however it really depends on many things: what iOS version you're using (not SDK), how many applications running in background, what exact memory you're using etc.
Just avoid the instant memory splashes (e.g. you're using 40 Mb of RAM, a...
Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
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What does Ruby have that Python doesn't, and vice versa?
There is a lot of discussions of Python vs Ruby, and I all find them completely unhelpful, because they all turn around why feature X sucks in language Y, or that claim language Y doesn't have X, although in fact it does. I also know exactly why I prefer Python, but that's also subjective, and would...
Android: Temporarily disable orientation changes in an Activity
...r, I noticed that if I rotate my phone it restarts the activity which is REALLY bad for the process that was running, and I get a Force Close.
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How to deal with INSTALL_PARSE_FAILED_INCONSISTENT_CERTIFICATES without uninstall?
I tried to reinstall an apk
16 Answers
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