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Difference between a user and a schema in Oracle?
......
Technically -- A schema is the set of metadata (data dictionary) used by the database,
typically generated using DDL. A schema defines attributes of the database, such as
tables, columns, and properties. A database schema is a description of the data in a
database.
...
How is location accuracy measured in Android?
...nyone know the proper interpretation of the accuracy measurements returned by getAccuracy()? For instance, are they calculated as:
...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
... for me to find the specific views in the storyboard source code (probably by searching the text for "17" initially), or at least a few likely candidates. From there I should be able to actually figure out which views these are in the storyboard which will make it a lot easier to identify the proble...
What does threadsafe mean?
...ode is thread-safe if it functions correctly during
simultaneous execution by multiple threads.”
“In particular, it must satisfy the need for multiple threads to
access the same shared data, …”
“…and the need for a shared piece of data to be accessed by only one
thread at any given time....
How to change owner of PostgreSql database?
...to admin database and update DB ownership:
psql
postgres=# REASSIGN OWNED BY old_name TO new_name;
This is a global equivalent of ALTER DATABASE command provided in Frank's answer, but instead of updating a particular DB, it change ownership of all DBs owned by 'old_name'.
The next step is to up...
Lists: Count vs Count() [duplicate]
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Count() is an extension method introduced by LINQ while the Count property is part of the List itself (derived from ICollection). Internally though, LINQ checks if your IEnumerable implements ICollection and if it does it uses the Count property. So at the end of the...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
...e to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
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Why don't C++ compilers define operator== and operator!=?
...t to provide a compiler-generated default for this operator can be guessed by what Stroustrup said about the default copy constructor in "The Design and Evolution of C++" (Section 11.4.1 - Control of Copying):
I personally consider it unfortunate
that copy operations are defined by
default a...
:: (double colon) operator in Java 8
...eference methods:
reduce(Math::max);
Note that this will be interpreted by the compiler, not by the JVM at runtime! Although it produces different bytecodes for all three code snippets, they are semantically equal, so the last two can be considered to be short (and probably more efficient) versio...
How do I pass the value (not the reference) of a JS variable to a function? [duplicate]
...ed to create a separate scope that saves the variable in its current state by passing it as a function parameter:
for (var i = 0; i < results.length; i++) {
(function (i) {
marker = results[i];
google.maps.event.addListener(marker, 'click', function() {
change_selection(i);
...