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What's the difference between a catalog and a schema in a relational database?
I used to think schema were the "upper wrapper" object before the database itself.
I mean DB.schema.<what_ever_object_name_under_schema> .
...
Convert JavaScript string in dot notation into an object reference
...P is asking for. However, if that's not the case, consider if any of these apply:
case 1: As the primary method of working with your data (e.g. as your app's default form of passing objects around and dereferencing them). Like asking "how can I look up a function or variable name from a string"...
Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
...s indeed 1 µs. This clock wraps around once it tops out (this typically happens after ~2^32 ticks, which is not very long for a 1 MHz clock). man clock says that since glibc 2.18 it is implemented with clock_gettime(CLOCK_PROCESS_CPUTIME_ID, ...) in Linux.
clock_gettime(CLOCK_MONOTONIC, ...) prov...
Difference between DateTime and Time in Ruby
...value describing the number of seconds since January 1, 1970 UTC, a thin wrapper around a POSIX-standard time_t value, and is bounded:
Time.at(0x7FFFFFFF)
# => Mon Jan 18 22:14:07 -0500 2038
Time.at(-0x7FFFFFFF)
# => Fri Dec 13 15:45:53 -0500 1901
Newer versions of Ruby are able to handle l...
What's the purpose of using braces (i.e. {}) for a single-line if or loop?
... described. There are some benefits. But, IMO, "always" rules don't always apply. So I don't wholly support
Always use a { } block - even for a single line // not OK, why ???
I'm not saying always use a {} block. If it's a simple enough condition & behavior, don't. If you suspect someone m...
What is the difference between the states selected, checked and activated in Android?
...ld).setChecked(mCheckStates.get(position));
} else if (getContext().getApplicationInfo().targetSdkVersion
>= android.os.Build.VERSION_CODES.HONEYCOMB) {
child.setActivated(mCheckStates.get(position));
}
}
Note the mCheckStates variable. It keeps track of which positi...
How do you Encrypt and Decrypt a PHP String?
...et a 16, 24, or 32 character random string in the
key option of the config/app.php file. Otherwise, encrypted values
will not be secure.
When to use EntityManager.find() vs EntityManager.getReference() with JPA
...
@Arthur Ronald what happens if there is a Version annotation in the entity called by getReference?
– David Hofmann
Mar 25 '16 at 13:28
...
Places where JavaBeans are used?
What is a JavaBean and why do I need it? Since I can create all apps with the class and interface structure? Why do I need beans? And can you give me some examples where beans are essential instead of classes and interfaces?
...
Logging levels - Logback - rule-of-thumb to assign log levels
...soon be) and the fix probably requires human intervention. The "2AM rule" applies here- if you're on call, do you want to be woken up at 2AM if this condition happens? If yes, then log it as "error".
warn: an unexpected technical or business event happened, customers may be affected, but probably ...