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Best way to test if a row exists in a MySQL table
...
A short example of @ChrisThompson's answer
Example:
mysql> SELECT * FROM table_1;
+----+--------+
| id | col1 |
+----+--------+
| 1 | foo |
| 2 | bar |
| 3 | foobar |
+----+--------+
3 rows in set (0.00 sec)
mysql> SELECT EXISTS(SELECT 1 FROM table_1 WHERE id = 1);...
Visual Studio “Could not copy” … during build
... Same here, VS2013. Quitting, deleting build artefacts, restarting -> all good.
– cacau
Feb 18 '14 at 9:13
50
...
How to break out from a ruby block?
...
p ["dog", "cat", "godzilla", "dogfrog", "woot", "catfrog"].first_frog
# => "dogfrog"
p ["hats", "coats"].first_frog
# => nil
p ["houses", "frogcars", "bottles", "superfrogs"].last_frog
# => "superfrogs"
One example would be doing something like this:
class Bar
def do_things
Foo.so...
Swift - class method which must be overridden by subclass
...ual {
// 'Implementation' provided by subclass
let fooImpl: (() -> String)
// Delegates to 'implementation' provided by subclass
func foo() -> String {
return fooImpl()
}
init(fooImpl: (() -> String)) {
self.fooImpl = fooImpl
}
}
class MyImpl:...
Terminal Multiplexer for Microsoft Windows - Installers for GNU Screen or tmux [closed]
...g a feature called Developer mode.
To enable developer mode, go to Start > Settings then typing "Use developer features" in the search box to find the setting. On the left hand navigation, you will then see a tab titled For developers. From within this tab, you will see a radio box to enable Dev...
How can I check if an element exists in the visible DOM?
...me()
Some of these methods return a NodeList, so be sure to check its length property, because a NodeList is an object, and therefore truthy.
For actually determining if an element exists as part of the visible DOM (like the question originally asked), Csuwldcat provides a better solution than ...
How to write a test which expects an Error to be thrown in Jasmine?
... describing in your test: "I expect this function to throw x"
expect(() => parser.parse(raw))
.toThrow(new Error('Parsing is not possible'));
If using Jasmine-Matchers you can also use one of the following when they suit the situation;
// I just want to know that an error was
// thrown and ...
SQLiteDatabase.query method
...Clause
the part you put after WHERE without that keyword, e.g. "column1 > 5"
should include ? for things that are dynamic, e.g. "column1=?" -> see whereArgs
whereArgs
specify the content that fills each ? in whereClause in the order they appear
the others
just like whereClause the st...
Enable remote connections for SQL Server Express 2012
... SQL Server Configuration Manager.
Go to SQL Server Network Configuration > Protocols for SQLEXPRESS.
Make sure TCP/IP is enabled.
So far, so good, and entirely expected. But then:
Right-click on TCP/IP and select Properties.
Verify that, under IP2, the IP Address is set to the computer's IP...
ArithmeticException: “Non-terminating decimal expansion; no exact representable decimal result”
...pported in releases prior to 5.)
As a corollary of computing the exact result, the rounding mode setting of a MathContext object with a precision setting of 0 is not used and thus irrelevant. In the case of divide, the exact quotient could have an infinitely long decimal expansion; for example, 1 di...